Vitamin E deficiency in humans is a very rare condition, occurring as a consequence of abnormalities in dietary fat absorption or metabolism rather than from a diet low in vitamin E.
Collectively the EARs, RDAs, AIs and ULs for
vitamin E
Vitamin E is a group of eight fat soluble compounds that include four tocopherols and four tocotrienols. Vitamin E deficiency, which is rare and usually due to an underlying problem with digesting dietary fat rather than from a diet low in vitami ...
and other essential nutrients are referred to as
Dietary Reference 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 (DRIs).
Vitamin E deficiency can cause
nerve problems due to poor conduction of electrical impulses along
nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system.
A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the e ...
s due to changes in
nerve membrane structure and function.
Signs and symptoms
Signs of vitamin E deficiency include the following:
* Neuromuscular problems – such as
spinocerebellar ataxia
Spinocerebellar ataxia (SCA) is a progressive, degenerative, genetic disease with multiple types, each of which could be considered a neurological condition in its own right. An estimated 150,000 people in the United States have a diagnosis of s ...
and
myopathies
In medicine, myopathy is a disease of the muscle in which the muscle fibers do not function properly. This results in muscular weakness. ''Myopathy'' means muscle disease (Greek : myo- ''muscle'' + patheia '' -pathy'' : ''suffering''). This mean ...
.
* Neurological problems – may include
dysarthria
Dysarthria is a speech sound disorder resulting from neurological injury of the motor component of the motor–speech system and is characterized by poor articulation of phonemes. In other words, it is a condition in which problems effectively ...
, absence of
deep tendon reflex
The stretch reflex (myotatic reflex), or more accurately "muscle stretch reflex", is a muscle contraction in response to stretching within the muscle. The reflex functions to maintain the muscle at a constant length. The term deep tendon reflex is ...
es, loss of the ability to sense vibration and
detect where body parts are in three dimensional space, and positive
Babinski sign
The plantar reflex is a reflex elicited when the sole of the foot is stimulated with a blunt instrument. The reflex can take one of two forms. In healthy adults, the plantar reflex causes a downward response of the hallux (flexion). An upward re ...
.
[
* ]Hemolytic anemia
Hemolytic anemia or haemolytic anaemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells (RBCs), either in the blood vessels (intravascular hemolysis) or elsewhere in the human body (extravascular). This most commonly ...
– due to oxidative damage to red blood cells[
* ]Retinopathy
Retinopathy is any damage to the retina of the eyes, which may cause vision impairment. Retinopathy often refers to retinal vascular disease, or damage to the retina caused by abnormal blood flow. Age-related macular degeneration is technically inc ...
immune response
An immune response is a reaction which occurs within an organism for the purpose of defending against foreign invaders. These invaders include a wide variety of different microorganisms including viruses, bacteria, parasites, and fungi which could ...
[
]
Causes
Vitamin E deficiency is rare. There are no records of it from simple lack of vitamin E in a person's diet, but it can arise from physiological abnormalities.[
* Premature, very low birth weight infants – birth weights less than 1500 grams (3.3 pounds).
* Rare disorders of fat metabolism – There is a rare genetic condition termed ]isolated vitamin E deficiency
Familial isolated vitamin E deficiency or Ataxia with vitamin E deficiency (AVED) is a rare autosomal recessive neurodegenerative disease. Symptoms are similar to those of Friedreich ataxia.
Cause
Familial isolated vitamin E deficiency is caused ...
or 'ataxia with isolated with vitamin E deficiency', caused by mutations in the gene for the tocopherol transfer protein. These individuals have an extremely poor capacity to absorb vitamin E and develop neurological complications that are reversed by high doses of vitamin E.
* Fat malabsorption – Some dietary fat is needed for the absorption of vitamin E from the gastrointestinal tract. Anyone diagnosed with cystic fibrosis
Cystic fibrosis (CF) is a rare genetic disorder that affects mostly the lungs, but also the pancreas, liver, kidneys, and intestine. Long-term issues include difficulty breathing and coughing up mucus as a result of frequent lung infections. O ...
, individuals who have had part or all of their stomach removed or who have had a gastric bypass, and individuals with malabsorptive problems such as Crohn's disease
Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea (which may be bloody if inflammation is severe), fever, abdominal distension ...
, liver disease
Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common.
Signs and symptoms
Some of the sig ...
or exocrine pancreatic insufficiency
Exocrine pancreatic insufficiency (EPI) is the inability to properly digest food due to a lack of digestive enzymes made by the pancreas. EPI is found in humans afflicted with cystic fibrosis and Shwachman–Diamond syndrome, and is common in ...
may not absorb fat (people who cannot absorb fat often pass greasy stools or have chronic diarrhea and bloating). Abetalipoproteinemia
Abetalipoproteinemia (also known as: Bassen-Kornzweig syndrome, microsomal triglyceride transfer protein deficiency disease, MTP deficiency, and betalipoprotein deficiency syndrome) is a disorder that interferes with the normal absorption of fat ...
is a rare inherited disorder of fat metabolism that results in poor absorption of dietary fat and vitamin E.
Diagnosis
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, E ...
defines deficiency as a serum concentration of less than 12 μmol/L. The symptoms can be enough for a diagnosis to be formed.
Treatment
Treatment is oral vitamin E supplementation.[
]
See also
* Familial isolated vitamin E deficiency
Familial isolated vitamin E deficiency or Ataxia with vitamin E deficiency (AVED) is a rare autosomal recessive neurodegenerative disease. Symptoms are similar to those of Friedreich ataxia.
Cause
Familial isolated vitamin E deficiency is caused ...
* Abetalipoproteinemia
Abetalipoproteinemia (also known as: Bassen-Kornzweig syndrome, microsomal triglyceride transfer protein deficiency disease, MTP deficiency, and betalipoprotein deficiency syndrome) is a disorder that interferes with the normal absorption of fat ...
* Tocopherol
Tocopherols (; TCP) are a class of organic chemical compounds (more precisely, various methylated phenols), many of which have vitamin E activity. Because the vitamin activity was first identified in 1936 from a dietary fertility factor in rats, i ...
References
External links
{{Nutritional pathology
Vitamin deficiencies