Premature greying of hair (PGH), also known as canities, can have negative effects on appearance, self-confidence, self-esteem, and social acceptance of the affected individual. Hair is said to have greyed prematurely if it occurs before the age of 20 years in

Europeans Europeans are the focus of European ethnology, the field of anthropology related to the various ethnic groups that reside in the states of Europe. Groups may be defined by common genetic ancestry, common language, or both. Pan and Pfeil (20 ...

, before 25 years in

Asians Asian people (or Asians, sometimes referred to as Asiatic people)United States National Library of Medicine. Medical Subject Headings. 2004. November 17, 200Nlm.nih.gov: ''Asian Continental Ancestry Group'' is also used for categorical purpos ...

, and before 30 years in Africans.

Cause

Cause of greying is incompletely understood. It is a complex multi-factorial process mainly considered to be an interplay of nutritional, genetic and environmental factors. Stress causing over-activation of the sympathetic nervous system increases

noradrenaline Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...

release in hair follicles. This overproduction causes depletion of the melanocyte stem cells which are required to produce

melanin Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino ...

, the pigment responsible for

hair color Human hair color is the pigmentation of human hair follicles due to two types of melanin: eumelanin and pheomelanin. Generally, if more melanin is present, the color of the hair is darker; if less melanin is present, the hair is lighter. The t ...

. Nutritional deficiencies like

vitamin B12 deficiency Vitamin B12 deficiency, also known as cobalamin deficiency, is the medical condition in which the blood and tissue have a lower than normal level of vitamin B12. Symptoms can vary from none to severe. Mild deficiency may have few or absent symp ...

, severe

iron deficiency Iron deficiency, or sideropenia, is the state in which a body lacks enough iron to supply its needs. Iron is present in all cells in the human body and has several vital functions, such as carrying oxygen to the tissues from the lungs as a key ...

, chronic protein loss,

copper deficiency Copper deficiency, or hypocupremia, is defined either as insufficient copper to meet the needs of the body, or as a serum copper level below the normal range. Symptoms may include fatigue, decreased red blood cells, early greying of the hair, an ...

are often found associated with premature greying of hairs. Other factors that have been incriminated are low serum

ferritin Ferritin is a universal intracellular protein that stores iron and releases it in a controlled fashion. The protein is produced by almost all living organisms, including archaea, bacteria, algae, higher plants, and animals. It is the primary ' ...

, and low

serum calcium Calcium ions (Ca2+) contribute to the physiology and biochemistry of organisms' cells. They play an important role in signal transduction pathways, where they act as a second messenger, in neurotransmitter release from neurons, in contraction of ...

and

vitamin D3 Cholecalciferol, also known as vitamin D3 and colecalciferol, is a type of vitamin D that is made by the skin when exposed to sunlight; it is found in some foods and can be taken as a dietary supplement. Cholecalciferol is made in the skin f ...

levels. Premature greying of hair has been observed with greater frequency among certain families, suggesting a familial predisposition for the condition. As hair pigmentation is a result of complex interaction between various genetic factors, it is thought that premature greying could be due to exhaustion of melanocyte's capability to produce hair pigmentation. Premature canities may occur alone as an autosomal dominant condition or in association with various

autoimmune In immunology, autoimmunity is the system of immune responses of an organism against its own healthy cells, tissues and other normal body constituents. Any disease resulting from this type of immune response is termed an "autoimmune disease". ...

or premature aging syndromes.

Down syndrome Down syndrome or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is usually associated with physical growth delays, mild to moderate intellectual dis ...

(

trisomy A trisomy is a type of polysomy in which there are three instances of a particular chromosome, instead of the normal two. A trisomy is a type of aneuploidy (an abnormal number of chromosomes). Description and causes Most organisms that reprodu ...

21) is characterized by features of accelerated aging including premature greying of hair and deficient

DNA repair DNA repair is a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. In human cells, both normal metabolic activities and environmental factors such as radiation can cause DNA da ...

. Premature greying needs to be differentiated from various genetic hypomelanotic hair disorders. Smoking is another factor that is considered to be related to premature greying of hair. Smoking results in generation of huge amount of reactive oxygen species leading to increased

oxidative stress Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal ...

culminating into damage to melanin producing cells, melanocytes. Prolonged exposure to

ultraviolet 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 ...

rays is considered to initiate similar processes in hair follicles resulting in premature greying of hair.

Management

If the cause is due to melanocyte stem cell interruption during the growth cycles due to stress or illness then the use of photobiomodulation for cellular

rejuvenation Rejuvenation is a medical discipline focused on the practical reversal of the aging process. Rejuvenation is distinct from life extension. Life extension strategies often study the causes of aging and try to oppose those causes in order to slow ...

may reverse the process.

Topical 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 ...

anti-aging compounds that are currently under investigation include photo protectors, such as cinnamidopropyltrimonium chloride and solid lipid

nanoparticle A nanoparticle or ultrafine particle is usually defined as a particle of matter that is between 1 and 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 10 ...

s as carriers for UV blockers, oral supplementation with l-cystine and

l-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 rol ...

, and topical melatonin.

References

{{reflist Hair coloring Premature events

Cause

Management

See also

References