A dietary supplement is a manufactured product intended to supplement one's diet by taking a
pill
Pill or The Pill may refer to:
Drugs
* Pill (pharmacy), referring to anything small for a specific dose of medicine
* "The Pill", a general nickname for the combined oral contraceptive pill
Film and television
* ''The Pill'' (film), a 2011 fil ...
tablet
Tablet may refer to:
Medicine
* Tablet (pharmacy), a mixture of pharmacological substances pressed into a small cake or bar, colloquially called a "pill"
Computing
* Tablet computer, a mobile computer that is primarily operated by touching the s ...
, powder, or liquid. A supplement can provide
nutrient
A nutrient is a substance used by an organism to survive, grow, and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi, and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...
s either extracted from food sources or that are synthetic in order to increase the quantity of their consumption. The class of nutrient compounds includes
vitamin
A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient that an organism needs in small quantities for the proper functioning of its ...
s,
minerals
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...
,
fiber
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
,
fatty acid
In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, fr ...
s, and
amino acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...
s. Dietary supplements can also contain substances that have not been confirmed as being essential to life, but are marketed as having a beneficial biological effect, such as plant
pigment
A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compo ...
s or
polyphenol
Polyphenols () are a large family of naturally occurring organic compounds characterized by multiples of phenol units. They are abundant in plants and structurally diverse. Polyphenols include flavonoids, tannic acid, and ellagitannin, some of ...
s. Animals can also be a source of supplement ingredients, such as
collagen
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole ...
from
chicken
The chicken (''Gallus gallus domesticus'') is a domesticated junglefowl species, with attributes of wild species such as the grey and the Ceylon junglefowl that are originally from Southeastern Asia. Rooster or cock is a term for an adult m ...
s or
fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
for example. These are also sold individually and in combination, and may be combined with nutrient ingredients. The
European Commission
The European Commission (EC) is the executive of the European Union (EU). It operates as a cabinet government, with 27 members of the Commission (informally known as "Commissioners") headed by a President. It includes an administrative body o ...
has also established harmonized rules to help insure that food supplements are safe and appropriately labeled.
Creating an industry estimated to have a 2020 value of $140.3 billion, there are more than 50,000 dietary supplement products marketed in the United States, where about 50% of the American adult population consumes dietary supplements.
Multivitamin
A multivitamin is a preparation intended to serve as a dietary supplement with vitamins, dietary minerals, and other nutritional elements. Such preparations are available in the form of tablets, capsules, pastilles, powders, liquids, or injectable ...
s are the most commonly used product among types of dietary supplements. The United States
National Institutes of Health
The National Institutes of Health, commonly referred to as NIH (with each letter pronounced individually), is the primary agency of the United States government responsible for biomedical and public health research. It was founded in the late ...
states that supplements "may be of value" for those who are nutrient deficient from their diet and receive approval from their medical provider.
In the United States, it is against federal regulations for supplement manufacturers to claim that these products prevent or treat any disease. Companies are allowed to use what is referred to as "Structure/Function" wording if there is substantiation of
scientific evidence
Scientific evidence is evidence that serves to either support or counter a scientific theory or hypothesis, although scientists also use evidence in other ways, such as when applying theories to practical problems. "Discussions about empirical ev ...
for a supplement providing a potential health effect. An example would be "_____ helps maintain healthy joints", but the label must bear a disclaimer that the
Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...
(FDA) "has not evaluated the claim" and that the dietary supplement product is not intended to "diagnose, treat, cure or prevent any disease", because only a
drug
A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via insuffla ...
can legally make such a claim. The FDA enforces these regulations and also prohibits the sale of supplements and supplement ingredients that are dangerous, or supplements not made according to standardized
good manufacturing practice
Current good manufacturing practices (cGMP) are those conforming to the guidelines recommended by relevant agencies. Those agencies control the authorization and licensing of the manufacture and sale of food and beverages, cosmetics, pharmaceutica ...
s (GMPs).
Definition
In the United States, the
Dietary Supplement Health and Education Act of 1994
The Dietary Supplement Health and Education Act of 1994 ("DSHEA"), is a 1994 statute of United States Federal legislation which defines and regulates dietary supplements. Under the act, supplements are regulated by the FDA for Good Manufacturing P ...
provides this description: "The Dietary Supplement Health and Education Act of 1994 (DSHEA) defines the term "dietary supplement" to mean a product (other than
tobacco
Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...
) intended to supplement the diet that bears or contains one or more of the following dietary ingredients: a vitamin, a mineral, an herb or other botanical, an amino acid, a dietary substance for use by man to supplement the diet by increasing the total dietary intake, or a concentrate,
metabolite
In biochemistry, a metabolite is an intermediate or end product of metabolism.
The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...
, constituent,
extract
An extract is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol, oil or water. Extracts may be sold as tinctures, absolutes or in powder form.
The aromatic principles of many spices, nuts, h ...
, or combination of any of the aforementioned ingredients. Furthermore, a dietary supplement must be labeled as a dietary supplement and be intended for ingestion and must not be represented for use as conventional food or as a sole item of a meal or of the diet. In addition, a dietary supplement cannot be approved or authorized for investigation as a new
drug
A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via insuffla ...
,
antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...
, or biologic, unless it was marketed as a food or a dietary supplement before such approval or authorization. Under DSHEA, dietary supplements are deemed to be food, except for purposes of the drug definition."
Per DSHEA, dietary supplements are consumed orally, and are mainly defined by what they are not: conventional foods (including meal replacements),
medical food
Medical foods are foods that are specially formulated and intended for the dietary management of a disease that has distinctive nutritional needs that cannot be met by normal diet alone. In the United States they were defined in the Food and Drug A ...
s,
preservative
A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or by ...
nasal spray
Nasal sprays are used to deliver medications locally in the nasal cavities or systemically. They are used locally for conditions such as nasal congestion and allergic rhinitis. In some situations, the nasal delivery route is preferred for syste ...
, or
topically
A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...
, as a lotion applied to the skin, do not qualify. FDA-approved drugs cannot be ingredients in dietary supplements. Supplement products are or contain
vitamins
A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient that an organism needs in small quantities for the proper functioning of its metabolism. Essential nutrien ...
amino acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...
plant
Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...
s or
animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motilit ...
s or
fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...
or
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
, or in the instance of
probiotic
Probiotics are live microorganisms promoted with claims that they provide health benefits when consumed, generally by improving or restoring the gut microbiota. Probiotics are considered generally safe to consume, but may cause bacteria-host i ...
s, are live bacteria. Dietary supplement ingredients may also be synthetic copies of naturally occurring substances (example:
melatonin
Melatonin is a natural product found in plants and animals. It is primarily known in animals as a hormone released by the pineal gland in the brain at night, and has long been associated with control of the sleep–wake cycle.
In vertebrates ...
). All products with these ingredients are required to be labeled as dietary supplements. Like foods and unlike drugs, no government approval is required to make or sell dietary supplements; the manufacturer confirms the safety of dietary supplements but the government does not; and rather than requiring risk–benefit analysis to prove that the product can be sold like a drug, such assessment is only used by the FDA to decide that a dietary supplement is unsafe and should be removed from market.
Types
Vitamins
A vitamin is an
organic compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...
required by an
organism
In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...
as a vital
nutrient
A nutrient is a substance used by an organism to survive, grow, and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi, and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...
in limited amounts.Lieberman, S and Bruning, N (1990). The Real Vitamin & Mineral Book. NY: Avery Group, 3, An organic chemical compound (or related set of compounds) is called a vitamin when it cannot be synthesized in sufficient quantities by an organism and must be obtained from the diet. The term is conditional both on the circumstances and on the particular organism. For example,
ascorbic acid
Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits and vegetables, also sold as a dietary supplement and as a topical 'serum' ingredient to treat melasma (dark pigment spots) an ...
(vitamin C) is a vitamin for anthropoid primates,
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...
s,
guinea pig
The guinea pig or domestic guinea pig (''Cavia porcellus''), also known as the cavy or domestic cavy (), is a species of rodent belonging to the genus ''Cavia'' in the family Caviidae. Breeders tend to use the word ''cavy'' to describe the ani ...
s and
bat
Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most bi ...
s, but not for other mammals. Vitamin D is not an essential nutrient for people who get sufficient exposure to
ultraviolet light
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation i ...
, either from the sun or an artificial source, as they synthesize vitamin D in skin. Humans require thirteen vitamins in their diet, most of which are actually groups of related molecules, "vitamers", (e.g. vitamin E includes tocopherols and tocotrienols, vitamin K includes vitamin K1 and K2). The list: vitamins A, C, D, E, K, Thiamine (B1), Riboflavin (B2), Niacin (B3), Pantothenic Acid (B5), Vitamin B6, Biotin (B7), Folate (B9) and Vitamin B12. Vitamin intake below recommended amounts can result in signs and symptoms associated with vitamin deficiency. There is little evidence of benefit when vitamins are consumed as a dietary supplement by those who are healthy and have a nutritionally adequate diet.
The
U.S. Institute of Medicine
The National Academy of Medicine (NAM), formerly called the Institute of Medicine (IoM) until 2015, is an American nonprofit, non-governmental organization. The National Academy of Medicine is a part of the National Academies of Sciences, Eng ...
sets tolerable upper intake levels (ULs) for some of the vitamins. This does not prevent dietary supplement companies from selling products with content per serving higher than the ULs. For example, the UL for vitamin D is 100 µg (4,000 IU), but products are available without prescription at 10,000 IU.
Minerals
Minerals are the
exogenous
In a variety of contexts, exogeny or exogeneity () is the fact of an action or object originating externally. It contrasts with endogeneity or endogeny, the fact of being influenced within a system.
Economics
In an economic model, an exogeno ...
chemical element
A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species. Unlike chemical compounds, chemical elements cannot be broken down into simpler sub ...
s indispensable for life. Four minerals –
carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent
In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with o ...
,
hydrogen
Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...
,
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
, and
nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
– are essential for life but are so ubiquitous in food and drink that these are not considered nutrients and there are no recommended intakes for these as minerals. The need for nitrogen is addressed by requirements set for protein, which is composed of nitrogen-containing amino acids.
Sulfur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...
is essential, but for humans, not identified as having a recommended intake per se. Instead, recommended intakes are identified for the sulfur-containing amino acids
methionine
Methionine (symbol Met or M) () is an essential amino acid in humans. As the precursor of other amino acids such as cysteine and taurine, versatile compounds such as SAM-e, and the important antioxidant glutathione, methionine plays a critical ro ...
and
cysteine
Cysteine (symbol Cys or C; ) is a semiessential proteinogenic amino acid with the formula . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile.
When present as a deprotonated catalytic residue, sometime ...
. There are dietary supplements that provide sulfur, such as taurine and
methylsulfonylmethane
Methylsulfonylmethane (MSM) is an organosulfur compound with the formula (CH3)2SO2. It is also known by several other names including methyl sulfone and dimethyl sulfone (DMSO2). This colorless solid features the sulfonyl functional group and is t ...
.
The essential nutrient minerals for humans, listed in order by weight needed to be at the
Recommended Dietary Allowance
The Dietary Reference Intake (DRI) is a system of nutrition recommendations from the National Academy of Medicine (NAM) of the National Academies (United States). It was introduced in 1997 in order to broaden the existing guidelines known as Reco ...
or
Adequate Intake
The Dietary Reference Intake (DRI) is a system of nutrition recommendations from the National Academy of Medicine (NAM) of the National Academies (United States). It was introduced in 1997 in order to broaden the existing guidelines known as Reco ...
are
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosphe ...
,
chlorine
Chlorine is a chemical element with the Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate betwee ...
,
sodium
Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable iso ...
,
calcium
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to ...
,
phosphorus
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...
,
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...
,
iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
,
zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...
,
manganese
Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy use ...
,
copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
,
iodine
Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a vi ...
,
chromium
Chromium is a chemical element with the symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal.
Chromium metal is valued for its high corrosion resistance and hardne ...
,
molybdenum
Molybdenum is a chemical element with the symbol Mo and atomic number 42 which is located in period 5 and group 6. The name is from Neo-Latin ''molybdaenum'', which is based on Ancient Greek ', meaning lead, since its ores were confused with lea ...
cobalt
Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, pr ...
(the last as a component of vitamin B12). There are other minerals which are essential for some plants and animals, but may or may not be essential for humans, such as
boron
Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has th ...
and
silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic tab ...
. Essential and purportedly essential minerals are marketed as dietary supplements, individually and in combination with vitamins and other minerals.
Although as a general rule, dietary supplement labeling and marketing are not allowed to make disease prevention or treatment claims, the U.S. FDA has for some foods and dietary supplements reviewed the science, concluded that there is significant scientific agreement, and published specifically worded allowed health claims. An initial ruling allowing a health claim for calcium dietary supplements and
osteoporosis
Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to bone fragility, and consequent increase in fracture risk. It is the most common reason for a broken bone ...
was later amended to include calcium supplements with or without vitamin D, effective January 1, 2010. Examples of allowed wording are shown below. In order to qualify for the calcium health claim, a dietary supplement must contain at least 20% of the Reference Dietary Intake, which for calcium means at least 260 mg/serving.
* "Adequate calcium throughout life, as part of a well-balanced diet, may reduce the risk of osteoporosis."
* "Adequate calcium as part of a healthful diet, along with physical activity, may reduce the risk of osteoporosis in later life."
* "Adequate calcium and vitamin D throughout life, as part of a well-balanced diet, may reduce the risk of osteoporosis."
* "Adequate calcium and vitamin D as part of a healthful diet, along with physical activity, may reduce the risk of osteoporosis in later life."
In the same year, the European Food Safety Authority also approved a dietary supplement health claim for calcium and vitamin D and the reduction of the risk of osteoporotic fractures by reducing bone loss.
The U.S. FDA also approved Qualified Health Claims (QHCs) for various health conditions for calcium, selenium and
chromium picolinate
Chromium(III) picolinate is a chemical compound with the formula Cr(C5H4N(CO2H))3, commonly abbreviated as CrPic3. It is sold as a nutritional supplement to treat type 2 diabetes and promote weight loss. This bright-red coordination compound is de ...
. QHCs are supported by scientific evidence, but do not meet the more rigorous "significant scientific agreement" standard required for an authorized health claim. If dietary supplement companies choose to make such a claim then the FDA stipulates the exact wording of the QHC to be used on labels and in marketing materials. The wording can be onerous: "One study suggests that selenium intake may reduce the risk of
bladder cancer
Bladder cancer is any of several types of cancer arising from the tissues of the urinary bladder. Symptoms include blood in the urine, pain with urination, and low back pain. It is caused when epithelial cells that line the bladder become mali ...
in women. However, one smaller study showed no reduction in risk. Based on these studies, FDA concludes that it is highly uncertain that selenium supplements reduce the risk of bladder cancer in women."
Proteins and amino acids
Protein-containing supplements, either ready-to-drink or as powders to be mixed into water, are marketed as aids to people recovering from illness or injury, those hoping to thwart the
sarcopenia
Sarcopenia is a type of muscle loss (muscle atrophy) that occurs with aging and/or immobility. It is characterized by the degenerative loss of skeletal muscle mass, quality, and strength. The rate of muscle loss is dependent on exercise level, c ...
of old age, to athletes who believe that strenuous physical activity increases protein requirements, to people hoping to lose weight while minimizing muscle loss, i.e., conducting a
protein-sparing modified fast
A protein-sparing modified fast or PSMF diet is a type of a very-low-calorie diet (<800 kcal per day) with a high proportion of protein calories and simultaneous restriction of carbohydrate and fat. It includes a
, and to people who want to increase muscle size for performance and appearance. Whey protein is a popular ingredient, but products may also incorporate
casein
Casein ( , from Latin ''caseus'' "cheese") is a family of related phosphoproteins (CSN1S1, αS1, aS2, CSN2, β, K-casein, κ) that are commonly found in mammalian milk, comprising about 80% of the proteins in cow's milk and between 20% and 60% of ...
pea
The pea is most commonly the small spherical seed or the seed-pod of the flowering plant species ''Pisum sativum''. Each pod contains several peas, which can be green or yellow. Botanically, pea pods are fruit, since they contain seeds and d ...
,
hemp
Hemp, or industrial hemp, is a botanical class of ''Cannabis sativa'' cultivars grown specifically for industrial or medicinal use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest growing plants o ...
or rice protein. A meta-analysis found a moderate degree of evidence in favor of whey protein supplements use as a safe and effective adjunct to an athlete's training and recovery, including benefits for endurance, average power,
muscle mass
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle ...
Recommended Dietary Allowance
The Dietary Reference Intake (DRI) is a system of nutrition recommendations from the National Academy of Medicine (NAM) of the National Academies (United States). It was introduced in 1997 in order to broaden the existing guidelines known as Reco ...
(RDA) for adults is based on 0.8 grams protein per kilogram body weight. The recommendation is for sedentary and lightly active people. Scientific reviews can conclude that a high protein diet, when combined with exercise, will increase muscle mass and strength, or conclude the opposite. The International Olympic Committee recommends protein intake targets for both strength and endurance athletes at about 1.2–1.8 g/kg body mass per day. One review proposed a maximum daily protein intake of approximately 25% of energy requirements, i.e., approximately 2.0 to 2.5 g/kg.
The same protein ingredients marketed as dietary supplements can be incorporated into meal replacement and
medical food
Medical foods are foods that are specially formulated and intended for the dietary management of a disease that has distinctive nutritional needs that cannot be met by normal diet alone. In the United States they were defined in the Food and Drug A ...
products, but those are regulated and labeled differently from supplements. In the United States, "meal replacement" products are foods and are labeled as such. These typically contain protein, carbohydrates, fats, vitamins and minerals. There may be content claims such as "good source of protein", "low fat" or "lactose free". Medical foods, also nutritionally complete, are designed to be used while a person is under the care of a physician or other licensed healthcare professional. Liquid medical food products – for example,
Ensure
Ensure is an American brand of nutritional supplements and meal replacements manufactured by Abbott Laboratories.
A 237-ml (8-fl oz) bottle of Ensure Original contains 220 calories, six grams of fat, 15 grams of sugar, and nine grams of protei ...
– are available in regular and high protein versions.
Proteins are chains of
amino acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...
s. Nine of these proteinogenic amino acids are considered essential for humans because they cannot be produced from other compounds by the human body and so must be taken in as food. Recommended intakes, expressed as milligrams per kilogram of body weight per day, have been established. Other amino acids may be conditionally essential for certain ages or medical conditions. Amino acids, individually and in combinations, are sold as dietary supplements. The claim for supplementing with the
branched chain amino acid
A branched-chain amino acid (BCAA) is an amino acid having an aliphatic side-chain with a branch (a central carbon atom bound to three or more carbon atoms). Among the proteinogenic amino acids, there are three BCAAs: leucine, isoleucine, and va ...
s leucine, valine and isoleucine is for stimulating muscle protein synthesis. A review of the literature concluded this claim was unwarranted. In elderly people, supplementation with just leucine resulted in a modest (0.99 kg) increase in lean body mass. The non-essential amino acid
arginine
Arginine is the amino acid with the formula (H2N)(HN)CN(H)(CH2)3CH(NH2)CO2H. The molecule features a guanidino group appended to a standard amino acid framework. At physiological pH, the carboxylic acid is deprotonated (−CO2−) and both the am ...
, consumed in sufficient amounts, is thought to act as a donor for the synthesis of nitric oxide, a vasodilator. A review confirmed blood pressure lowering. Taurine, a popular dietary supplement ingredient with claims made for sports performance, is technically not an amino acid. It is synthesized in the body from the amino acid
cysteine
Cysteine (symbol Cys or C; ) is a semiessential proteinogenic amino acid with the formula . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile.
When present as a deprotonated catalytic residue, sometime ...
.
Bodybuilding supplements
Essential fatty acids
Fish oil is a commonly used fatty acid supplement because it is a source of omega-3 fatty acids. Fatty acids are strings of carbon atoms, having a range of lengths. If links are all single (C-C), then the fatty acid is called ''
saturated
Saturation, saturated, unsaturation or unsaturated may refer to:
Chemistry
* Saturation, a property of organic compounds referring to carbon-carbon bonds
** Saturated and unsaturated compounds
**Degree of unsaturation
** Saturated fat or fatty ac ...
''; with one double bond (C=C), it is called '' monounsaturated''; if there are two or more double bonds (C=C=C), it is called ''
polyunsaturated
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
The term often refers specifically to triglycerides (triple e ...
''. Only two fatty acids, both polyunsaturated, are considered essential to be obtained from the diet, as the others are synthesized in the body. The "essential" fatty acids are alpha-linolenic acid (ALA), an omega-3 fatty acid, and
linoleic acid
Linoleic acid (LA) is an organic compound with the formula COOH(CH2)7CH=CHCH2CH=CH(CH2)4CH3. Both alkene groups are cis-trans isomerism, ''cis''. It is a fatty acid sometimes denoted 18:2 (n-6) or 18:2 ''cis''-9,12. A linoleate is a salt (chem ...
(LA), an omega-6 fatty acid. ALA can be elongated in the body to create other omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
Plant oils, particularly seed and nut oils, contain ALA. Food sources of EPA and DHA are oceanic fish, whereas dietary supplement sources include fish oil, krill oil and marine algae extracts. The European Food Safety Authority (EFSA) identifies 250 mg/day for a combined total of EPA and DHA as Adequate Intake, with a recommendation that women pregnant or lactating consume an additional 100 to 200 mg/day of DHA. In the United States and Canada are
Adequate Intake
The Dietary Reference Intake (DRI) is a system of nutrition recommendations from the National Academy of Medicine (NAM) of the National Academies (United States). It was introduced in 1997 in order to broaden the existing guidelines known as Reco ...
s for ALA and LA over various stages of life, but there are no intake levels specified for EPA and/or DHA.
Supplementation with EPA and/or DHA does not appear to affect the risk of death, cancer or heart disease. Furthermore, studies of fish oil supplements have failed to support claims of preventing
heart attacks
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may tra ...
or
stroke
A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...
s. In 2017, the American Heart Association issued a science advisory stating that it could not recommend use of omega-3 fish oil supplements for primary prevention of
cardiovascular disease
Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, h ...
or stroke, although it reaffirmed supplementation for people who have a history of coronary heart disease.
Manufacturers have begun to include long chain polyunsaturated fatty acids DHA and
arachidonic acid
Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega-6 fatty acid 20:4(ω-6), or 20:4(5,8,11,14). It is structurally related to the saturated arachidic acid found in cupuaçu butter. Its name derives from the New Latin word ''arachi ...
(AA) into their formula milk for newborns, however, a 2017 review found that supplementation with DHA and AA does not appear to be harmful or beneficial to formula-fed infants.
Natural products
Dietary supplements can be manufactured using intact sources or
extract
An extract is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol, oil or water. Extracts may be sold as tinctures, absolutes or in powder form.
The aromatic principles of many spices, nuts, h ...
s from plants, animals, algae, fungi or lichens, including such examples as
ginkgo biloba
''Ginkgo biloba'', commonly known as ginkgo or gingko ( ), also known as the maidenhair tree, is a species of tree native to China. It is the last living species in the order Ginkgoales, which first appeared over 290 million years ago. Fossils ...
St. John's wort
''Hypericum perforatum'', known as St. John's wort, is a flowering plant in the family Hypericaceae and the type species of the genus ''Hypericum''.
Possibly a hybrid between '' H. maculatum'' and '' H. attenuatum'', the species can be found a ...
resveratrol
Resveratrol (3,5,4′-trihydroxy-''trans''-stilbene) is a stilbenoid, a type of natural phenol, and a phytoalexin produced by several plants in response to injury or when the plant is under attack by pathogens, such as bacteria or fungi. Sources ...
collagen
Collagen () is the main structural protein in the extracellular matrix found in the body's various connective tissues. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole ...
. Products bearing promotional claims of health benefits are sold without requiring a prescription in pharmacies,
supermarket
A supermarket is a self-service Retail#Types of outlets, shop offering a wide variety of food, Drink, beverages and Household goods, household products, organized into sections. This kind of store is larger and has a wider selection than earli ...
buyers club
A buyers club or buying club is a club organized to pool members' collective buying power, enabling them to make purchases at lower prices than are generally available, or to purchase goods that might be difficult to obtain independently.
Some key ...
s, direct selling organizations, and the internet. While most of these products have a long history of use in
herbalism
Herbal medicine (also herbalism) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. With worldwide research into pharmacology, some herbal medicines have been translated into modern reme ...
and various forms of traditional medicine, concerns exist about their actual efficacy, safety and consistency of quality. Canada has published a manufacturer and consumer guide describing quality, licensing, standards, identities, and common contaminants of natural products.
In 2019, sales of herbal supplements just in the United States alone were $9.6 billion, with the market growing at approximately 8.6% per year, with cannabidiol and mushroom product sales as the highest. Italy, Germany, and
Eastern Europe
Eastern Europe is a subregion of the Europe, European continent. As a largely ambiguous term, it has a wide range of geopolitical, geographical, ethnic, cultural, and socio-economic connotations. The vast majority of the region is covered by Russ ...
an countries were leading consumers of botanical supplements in 2016, with
European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been des ...
market growth forecast to be $8.7 billion by 2020.
Probiotics
Claimed benefits of using
probiotic
Probiotics are live microorganisms promoted with claims that they provide health benefits when consumed, generally by improving or restoring the gut microbiota. Probiotics are considered generally safe to consume, but may cause bacteria-host i ...
supplements are not supported by sufficient clinical evidence. Meta-analysis studies have reported a modest reduction of antibiotic-associated diarrhea and acute diarrhea in children taking probiotics. There is limited evidence in support of adults using mono-strain and multi-strain containing probiotics for the alleviation of symptoms associated with irritable bowel syndrome. Probiotic supplements are generally regarded as safe.
Fertility
A meta-analysis provided preliminary evidence that men treated with supplements containing selenium,
zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...
carnitine
Carnitine is a quaternary ammonium compound involved in metabolism in most mammals, plants, and some bacteria. In support of energy metabolism, carnitine transports long-chain fatty acids into mitochondria to be oxidized for energy production, an ...
s reported improvements in total sperm count, concentration, motility, and morphology. A review concluded that omega-3 taken through supplements and diet might improve semen quality in infertile men. A 2021 review also supported selenium, zinc, omega-3 fatty acids, coenzyme Q10 or carnitines, but warned that "excessive use of antioxidants may be detrimental to the spermatic function and many of the over-the-counter supplements are not scientifically proven to improve fertility."
There is low quality and insufficient evidence for the use of oral antioxidant supplements as a viable treatment for
subfertile
Infertility is the inability of a person, animal or plant to reproduce by natural means. It is usually not the natural state of a healthy adult, except notably among certain eusocial species (mostly haplodiploid insects). It is the normal stat ...
woman. A review provided evidence that taking
dehydroepiandrosterone
Dehydroepiandrosterone (DHEA), also known as androstenolone, is an endogenous steroid hormone precursor. It is one of the most abundant circulating steroids in humans. DHEA is produced in the adrenal glands, the gonads, and the brain. It functio ...
before starting an ''in vitro'' fertilization series may increase pregnancy rates and decrease miscarriage likelihood.
Prenatal
Prenatal vitamins
Prenatal vitamins, also known as prenatal supplements, are vitamin and mineral supplements intended to be taken before and during pregnancy and during postnatal lactation. Although not intended to replace a healthy diet, prenatal vitamins provid ...
are dietary supplements commonly given to pregnant women to supply nutrients that may reduce health complications for the mother and
fetus
A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal deve ...
. Although prenatal vitamins are not meant to substitute for dietary nutrition, prenatal supplementation may be beneficial for pregnant women at risk of nutrient deficiencies because of diet limitations or restrictions. The most common components in prenatal vitamins include vitamins B6, folate, B12, C, D, E,
iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
and
calcium
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to ...
.
Sufficient intake of vitamin B6 can lower the risk of early pregnancy loss and relieve symptoms of
morning sickness
Morning sickness, also called nausea and vomiting of pregnancy (NVP), is a symptom of pregnancy that involves nausea or vomiting. Despite the name, nausea or vomiting can occur at any time during the day. Typically the symptoms occur between th ...
. Folate is also an essential nutrient for pregnant women to prevent neural tube defects. In 2006, the World Health Organization endorsed the recommendation for women of child-bearing age to consume 400 micrograms of folate through the diet daily if planning a pregnancy. A 2013 review found folic acid supplementation during pregnancy did not affect the mother's health other than a risk reduction on low pre-delivery serum folate and megaloblastic anemia. There is little evidence to suggest that vitamin D supplementation improves prenatal outcomes in hypertensive disorders and
gestational diabetes
Gestational diabetes is a condition in which a woman without diabetes develops high blood sugar levels during pregnancy. Gestational diabetes generally results in few symptoms; however, it increases the risk of pre-eclampsia, depression, and of ...
. Evidence does not support the routine use of vitamin E supplementation during pregnancy to prevent adverse events, such as preterm birth, fetal or neonatal death, or maternal hypertensive disorders.
Iron supplementation can lower the risk of
iron deficiency anemia
Iron-deficiency anemia is anemia caused by a lack of iron. Anemia is defined as a decrease in the number of red blood cells or the amount of hemoglobin in the blood. When onset is slow, symptoms are often vague such as feeling tired, weak, shor ...
for pregnant women. In 2020, the World Health Organization updated recommendations for adequate calcium levels during pregnancy to prevent
hypertensive disorders
Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high blo ...
.
Pharmacotherapy
Individuals with
hypokalemic sensory overstimulation
Hypokalemic sensory overstimulation is characterized by a subjective experience of sensory overload and a relative resistance to lidocaine local anesthesia. The sensory overload is treatable with oral potassium gluconate. Individuals with this con ...
are sometimes diagnosed as having attention deficit hyperactivity disorder (ADHD), raising the possibility that a subtype of ADHD has a cause that can be understood mechanistically and treated in a novel way. The sensory overload is treatable with oral
potassium gluconate
Potassium gluconate is the potassium salt of the conjugate base of gluconic acid. It is also referred to as 2,3,4,5,6-pentahydroxycaproic acid potassium salt, D-gluconic acid potassium salt, or potassium D-gluconate.
It contains 16.69% potassium ...
.
Industry
In 2020, the American market for dietary supplements was valued at $140.3 billion, with the
economic impact
An economic impact analysis (EIA) examines the effect of an event on the economy in a specified area, ranging from a single neighborhood to the entire globe. It usually measures changes in business revenue, business profits, personal wages, and ...
in the United States for 2016 estimated at $122 billion, including employment wages and taxes. A 2020 analysis projected that the global market for
vitamin
A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient that an organism needs in small quantities for the proper functioning of its ...
s and dietary supplement products would reach $196.6 billion by 2028, where the growth in
market size
In economics, a market is a composition of systems, institutions, procedures, social relations or infrastructures whereby parties engage in exchange. While parties may exchange goods and services by barter, most markets rely on sellers offering ...
is largely attributed to recent technological advancements in product manufacturing, increased demand for products advertised as healthy, increased product availability, and population aging.
Adulteration, contamination and mislabeling
Over the period 2008 to 2011, the
Government Accountability Office
The U.S. Government Accountability Office (GAO) is a legislative branch government agency that provides auditing, evaluative, and investigative services for the United States Congress. It is the supreme audit institution of the federal govern ...
(GAO) of the United States received 6,307 reports of health problems (identified as adverse events) from use of dietary supplements containing a combination of ingredients in manufactured vitamins, minerals or other supplement products, with 92% of tested herbal supplements containing
lead
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...
and 80% containing other chemical contaminants. Using undercover staff, the GAO also found that supplement retailers intentionally engaged in "unequivocal deception" to sell products advertised with baseless health claims, particularly to elderly consumers.
Consumer Reports
Consumer Reports (CR), formerly Consumers Union (CU), is an American nonprofit consumer organization dedicated to independent product testing, investigative journalism, consumer-oriented research, public education, and consumer advocacy.
Founded ...
also reported unsafe levels of arsenic, cadmium, lead and mercury (element), mercury in several protein powder products. The Canadian Broadcasting Corporation (CBC) reported that protein spiking, i.e., the addition of amino acids to manipulate protein content analysis, was common. Many of the companies involved challenged CBC's claim.
A 2013 study on herbal supplements found that many products were of low quality, one third did not contain the active ingredient(s) claimed, and one third contained unlisted substances. In a Genetics, genetic analysis of herbal supplements, 78% of samples contained animal DNA that was not identified as an ingredient on the product labels. In some botanical products, undeclared ingredients were used to increase the bulk of the product and reduce its cost of manufacturing, while potentially violating certain religious and/or cultural limitations on consuming animal ingredients, such as cow, buffalo or deer. In 2015, the New York Attorney General (NY-AG) identified four major retailers with dietary supplement products that contained fraudulent and potentially dangerous ingredients, requiring the companies to remove the products from retail stores. According to the NY-AG, only about 20% of the herbal supplements tested contained the plants claimed. The methodology used by the NY-AG was disputed. The test involves looking for DNA fragments from the plants named as the dietary supplement ingredients in the products. One scientist said that it was possible that the extraction process used to create the supplements removed or destroyed all DNA. This, however, would not explain the presence of DNA from plants such as rice or wheat, that were not listed as ingredients.
A study of dietary supplements sold between 2007 and 2016 identified 776 that contained unlisted pharmaceutical drugs, many of which could interact with other medications and lead to hospitalization. 86% of the adulterated supplements were marketed for weight loss and sexual performance, with many containing prescription erectile dysfunction medication. Bodybuilding, Muscle building supplements were contaminated with anabolic steroids that can lead to health complications affecting the kidney, the heart, and cause gynecomastia. Multiple bodybuilding products also contained antidepressants and antihistamines. Despite these findings, fewer than half of the adulterated supplements were recalled.
Regulatory compliance
The
European Commission
The European Commission (EC) is the executive of the European Union (EU). It operates as a cabinet government, with 27 members of the Commission (informally known as "Commissioners") headed by a President. It includes an administrative body o ...
has published harmonized rules on supplement products to assure consumers have minimal health risks from using dietary supplements and are not misled by advertising.
In the United States and Canada, dietary supplements are considered a subset of foods, and are regulated accordingly. The U.S. Food and Drug Administration (FDA) monitors supplement products for accuracy in advertising and labeling. Dietary supplements are regulated by the FDA as food products subject to compliance with current Good Manufacturing Practices (CGMP) and labeling with science-based ingredient descriptions and advertising. When finding CGMP or advertising violations, FDA warning letters are used to notify manufacturers of impending enforcement action, including search and seizure, injunction, and fine (penalty), financial penalties. Examples between 2016 and 2018 of CGMP and advertising violations by dietary supplement manufacturers included several with illegal compositions or advertising of vitamins and minerals.
The U.S. Federal Trade Commission, which litigates against deceptive advertising in marketed products, established a consumer center to assist reports of false health claims in product advertising for dietary supplements. In 2017, the FTC successfully sued nine manufacturers for deceptive advertising of dietary supplements.
Adverse effects
In the United States, manufacturers of dietary supplements are required to demonstrate safety of their products before approval is granted for commerce. Despite this caution, numerous adverse effects have been reported, including muscle cramps, hair loss, joint pain, liver disease, and allergy, allergic reactions, with 29% of the adverse effects resulting in hospitalization, and 20% in serious injuries or illnesses. The potential for adverse effects also occurs when individuals consume more than the necessary daily amount of
vitamin
A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an Nutrient#Essential nutrients, essential micronutrient that an organism needs in small quantities for the proper functioning of its ...
s or minerals that are needed to maintain normal body processes and functions. The incidence of adverse effects reported to the Food and Drug Administration, FDA were due to "combination products" that contain multiple ingredients, whereas dietary supplements containing a single vitamin, mineral, lipid product, and herbal product were less likely to cause adverse effects related to excess supplementation.
Among general reasons for the possible harmful effects of dietary supplements are: a) absorption in a short time, b) manufacturing quality and contamination, and c) enhancing both positive and negative effects at the same time. The incidence of hepatotoxicity, liver injury from herbal and dietary supplements is about 16–20% of all supplement products causing injury, with the occurrence growing globally over the early 21st century. The most common liver injuries from weight loss and bodybuilding supplements involve Hepatocyte, hepatocellular damage with resulting jaundice, and the most common supplement ingredients attributed to these injuries are green tea catechins, anabolic steroids, and the herbal
extract
An extract is a substance made by extracting a part of a raw material, often by using a solvent such as ethanol, oil or water. Extracts may be sold as tinctures, absolutes or in powder form.
The aromatic principles of many spices, nuts, h ...
, Aegle marmelos, aegeline. Weight loss supplements have also had adverse psychiatry, psychiatric effects. Some dietary supplements may also have adverse interactions with prescription medications that may enhance side effects or decrease therapeutic effects of medications.
Society and culture
Public health
Work done by scientists in the early 20th century on identifying individual nutrients in food and developing ways to manufacture them raised hopes that optimal health could be achieved and diseases prevented by adding them to food and providing people with dietary supplements; while there were successes in preventing vitamin deficiencies, and preventing conditions like neural tube defects by supplementation and food fortification with folic acid, no targeted supplementation or fortification strategies to prevent major diseases like cancer or cardiovascular diseases have proved successful.
For example, while increased consumption of fruits and vegetables are related to decreases in mortality, cardiovascular diseases and cancers, supplementation with key factors found in fruits and vegetable, like antioxidants, vitamins, or minerals, do not help and some have been found to be harmful in some cases. In general, as of 2016, robust clinical data is lacking, that shows that any kind of dietary supplementation does more good than harm for people who are healthy and eating a reasonable diet but there is clear data showing that dietary pattern and lifestyle choices are associated with health outcomes.
As a result of the lack of good data for supplementation and the strong data for dietary pattern, public health recommendations for healthy eating urge people to eat a plant-based diet of whole foods, minimizing processed food, salt and sugar and to get exercise daily, and to abandon Western pattern diets and a sedentary lifestyle.
Legal regulation
United States
The regulation of food and dietary supplements by the U.S. Food and Drug Administration (FDA) is governed by various statutes enacted by the United States Congress. Pursuant to the Federal Food, Drug, and Cosmetic Act and accompanying legislation, the FDA has authority to oversee the quality of substances sold as food in the United States, and to monitor claims made in the Packaging and labeling, labeling about both the composition and the health benefits of foods.
Substances which the FDA regulates as food are subdivided into various categories, including foods, food additives, added substances (man-made substances which are not intentionally introduced into food, but nevertheless end up in it), and dietary supplements. The specific standards which the FDA exercises differ from one category to the next. Furthermore, the FDA has been granted a variety of means by which it can address violations of the standards for a given category of substances.
Dietary supplement manufacture is required to comply with the good manufacturing practices established in 2007. The FDA can visit manufacturing facilities, send FDA warning letter, Warning Letters if not in compliance with GMPs, stop production, and if there is a health risk, require that the company conduct a recall. Only after a dietary supplement product is marketed, may the FDA's Center for Food Safety and Applied Nutrition (CFSAN) review the products for safety and effectiveness.
European Union
The
European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been des ...
's (EU) Food Supplements Directive of 2002 requires that supplements be demonstrated to be safe, both in dosages and in purity. Only those supplements that have been proven to be safe may be sold in the EU without prescription. As a category of food, food supplements cannot be labeled with drug claims but can bear health claims and nutrition claims.
The dietary supplements industry in the United Kingdom (UK), one of the 28 countries in the bloc, strongly opposed the Directive. In addition, a large number of consumers throughout Europe, including over one million in the UK, and various doctors and scientists, had signed petitions by 2005 against what are viewed by the petitioners as unjustified restrictions of consumer choice. In 2004, along with two British trade associations, the Alliance for Natural Health (ANH) had a legal challenge to the Food Supplements Directive referred to the European Court of Justice by the High Court in London.
Although the European Court of Justice's Advocate General subsequently said that the bloc's plan to tighten rules on the sale of
vitamins
A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient that an organism needs in small quantities for the proper functioning of its metabolism. Essential nutrien ...
and food supplements should be scrapped, he was eventually overruled by the European Court, which decided that the measures in question were necessary and appropriate for the purpose of protecting public health. ANH, however, interpreted the ban as applying only to synthetically produced supplements, and not to vitamins and minerals normally found in or consumed as part of the diet. Nevertheless, the European judges acknowledged the Advocate General's concerns, stating that there must be clear procedures to allow substances to be added to the permitted list based on scientific evidence. They also said that any refusal to add the product to the list must be open to challenge in the courts.
Fraudulent products during the COVID-19 outbreak
During the COVID-19 pandemic in the United States, the Food and Drug Administration, FDA and Federal Trade Commission (FTC) warned consumers about fraud, marketing scams of fraudulent supplement products, including homeopathy, homeopathic remedies, cannabidiol, cannabidiol products, teas, essential oils, tinctures and colloidal silver, among others. By August 2020, the FDA and FTC had issued FDA warning letter, warning letters to dozens of companies advertising scam products, which were purported "to be drugs, medical devices or vaccines. Products that claim to cure, mitigate, treat, diagnose or prevent disease, but are not proven safe and effective for those purposes, defraud consumers of money and can place consumers at risk for serious harm"
Research
Examples of ongoing government research organizations to better understand the potential health properties and safety of dietary supplements are the European Food Safety Authority, the Office of Dietary Supplements of the United States
National Institutes of Health
The National Institutes of Health, commonly referred to as NIH (with each letter pronounced individually), is the primary agency of the United States government responsible for biomedical and public health research. It was founded in the late ...
, the Natural Health Products Directorate, Natural and Non-prescription Health Products Directorate of Canada, and the Therapeutic Goods Administration of Australia. Together with public and private research groups, these agencies construct databases on supplement properties, perform research on quality, safety, and population trends of supplement use, and evaluate the potential clinical efficacy of supplements for maintaining health or lowering disease risk.
Databases
As continual research on the properties of supplements accumulates, databases or fact sheets for various supplements are updated regularly, including the Dietary Supplement Label Database, Dietary Supplement Ingredient Database, and Dietary Supplement Facts Sheets of the United States. In Canada where a license is issued when a supplement product has been proven by the manufacturer and government to be safe, effective and of sufficient quality for its recommended use, an eight-digit Natural Product Number is assigned and recorded in a Licensed Natural Health Products Database. The European Food Safety Authority maintains a compendium of botanical ingredients used in manufacturing of dietary supplements.
In 2015, the Department of Health (Australia), Australian Government's Department of Health published the results of a review of herbal supplements to determine if any were suitable for coverage by health insurance. Establishing guidelines to assess safety and efficacy of botanical supplement products, the European Medicines Agency provided criteria for evaluating and grading the quality of clinical research in preparing monographs about herbal supplements. In the United States, the National Center for Complementary and Integrative Health of the National Institutes of Health provides fact sheets evaluating the safety, potential effectiveness and side effects of many botanical products.
Quality and safety
To assure supplements have sufficient quality, standardization, and safety for public consumption, research efforts have focused on development of reference materials for supplement manufacturing and monitoring. High-dose products have received research attention, especially for emergency situations such as vitamin A deficiency in malnutrition of children, and for women taking folate supplements to reduce the risk of breast cancer.
Population monitoring
In the United States, the National Health and Nutrition Examination Survey (NHANES) has investigated habits of using dietary supplements in context of total nutrient intakes from the diet in adults and children. Over the period of 1999 to 2012, use of multivitamins decreased, and there was wide variability in the use of individual supplements among subgroups by age, sex, race/ethnicity, and educational status. Particular attention has been given to use of folate supplements by young women to reduce the risk of fetus, fetal neural tube defects.
Clinical studies
Limited human research has been conducted on the potential for dietary supplementation to affect disease risk. Examples:
* vitamin D acute respiratory tract infections
* mineral (nutrient), iron maternal iron deficiency anemia and adverse effects on the
fetus
A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal deve ...
* multiple supplements no evidence of benefit to lower risk of death, cardiovascular diseases or cancer
* magnesium supplementation in reducing all-cause and cancer mortality, as well as improving glucose parameters in people with diabetes and insulin-sensitivity parameters in those at high risk of diabetes.
* folate alone or with B vitamins
stroke
A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...
A 2017 academic review indicated a rising Incidence (epidemiology), incidence of liver injury from use of herbal and dietary supplements, particularly those with steroids, green tea extract, or multiple ingredients.
Absence of benefit
The potential benefit of using essential nutrient dietary supplements to lower the risk of diseases has been refuted by findings of no effect or weak evidence in numerous clinical reviews, such as for HIV, or tuberculosis.
Reporting bias
A review of clinical trials registered at clinicaltrials.gov, which would include both drugs and supplements, reported that nearly half of completed trials were sponsored wholly or partially by industry. This does not automatically imply bias, but there is evidence that because of selective non-reporting, results in support of a potential drug or supplement ingredient are more likely to be published than results that do not demonstrate a statistically significant benefit. One review reported that fewer than half of the registered clinical trials resulted in publication in peer-reviewed journals.
Future
Improving public information about use of dietary supplements involves investments in professional training programs, further studies of population and nutrient needs, expanding the database information, enhancing collaborations between governments and universities, and translating dietary supplement research into useful information for consumers, health professionals, scientists, and policymakers. Future demonstration of efficacy from use of dietary supplements requires high-quality clinical research using rigorously qualified products and compliance with established guidelines for reporting of clinical trial results (e.g., Consolidated Standards of Reporting Trials, CONSORT guidelines).
Dietary Supplement Health and Education Act of 1994
The Dietary Supplement Health and Education Act of 1994 ("DSHEA"), is a 1994 statute of United States Federal legislation which defines and regulates dietary supplements. Under the act, supplements are regulated by the FDA for Good Manufacturing P ...
*
Multivitamin
A multivitamin is a preparation intended to serve as a dietary supplement with vitamins, dietary minerals, and other nutritional elements. Such preparations are available in the form of tablets, capsules, pastilles, powders, liquids, or injectable ...
* Dietary Supplements (database) (PubMed)
* Alternative medicine
* ConsumerLab.com
* Examine.com
* Natural Standard
References
Further reading
* List of resources that provides an overview of herbal and dietary supplements, including use, regulation, research, and cautionary information.
*
*
External links
*
*
{{DEFAULTSORT:Dietary Supplement
Dietary supplements,
Articles containing video clips