Greying of hair

Last updated
Greying of hair
Other namesGreying, graying, canities, achromotrichia
41 year old man with partial gray hair.jpg
A 41-year-old man with partially grey hair
Middle-aged man with gray hair and beard.jpg
The same man at age 56, with fully grey hair
Symptoms Loss of pigmentation in the hair.
Complications Psychological distress
CausesAging
TreatmentAccepting the condition, medications

Greying of hair, also known as greying, canities, or achromotrichia, is the progressive loss of pigmentation in the hair, eventually turning the hair grey or white which typically occurs naturally as people age.

Contents

Terminology

Greying of hair is the partial or complete process of a hair becoming grey or white. It is also known as canities or achromotrichia. The word "canities" is derived from the Latin word cānitiēs for "gray hair, old age".

Overview

Changes in hair color typically occur naturally as people age, eventually turning the hair grey and then white. This normally begins in the early to mid-twenties in men and late twenties in women. More than 60 percent of Americans have some grey hair by age 40. The age at which greying begins seems almost entirely due to genetics. Sometimes people are born with grey hair because they inherit the trait. [1]

The order in which greying happens is usually: nose hair, hair on the head, beard, body hair, eyebrows. [2]

Greying is a gradual process; according to a study by L'Oreal, overall, of those between 45 and 65 years old, 74% had some grey hair, covering an average of 27% of their head, and approximately 1 in 10 people had no grey hairs even after the age of 60. [3] [4]

Causes

Grey or white hair is not caused by a true grey or white pigment, but is due to a lack of pigmentation and melanin. The clear hairs appear as grey or white because of the way light is reflected from the hairs.

The change in hair color occurs when melanin ceases to be produced in the hair root and new hairs grow in without pigment. The stem cells at the base of hair follicles produce melanocytes, the cells that produce and store pigment in hair and skin. The death of the melanocyte stem cells causes the onset of greying. It remains unclear why the stem cells of one hair follicle may fail to activate well over a decade before those in adjacent follicles less than a millimeter apart.

In non-balding individuals, hair may grow faster once it turns grey. [5] Unlike in the skin where pigment production is continuous, melanogenesis in the hair is closely associated with stages of the hair cycle. Hair is actively pigmented in the anagen phase and is "turned off" during the catagen phase, and absent during telogen. [6] Thus, a single hair cannot be white on the root side, and colored on the terminal side.

Several genes appear to be responsible for the process of greying. Bcl2 and Bcl-w [7] were the first two discovered, then in 2016, the IRF4 (interferon regulatory factor 4) gene was announced after a study of 6,000 people living in five Latin American countries. However, it found that environmental factors controlled about 70% of cases of hair greying. [8]

In some cases, grey hair may be caused by thyroid deficiencies, Waardenburg syndrome or a vitamin B12 deficiency. [9] At some point in the human life cycle, cells that are located in the base of the hair's follicles slow, and eventually stop producing pigment. [10] Piebaldism is a rare autosomal dominant disorder of melanocyte development, which may cause a congenital white forelock. [11] : 867 

Greying of hair may be triggered by the accumulation of hydrogen peroxide and abnormally low levels of the enzyme catalase, which breaks down hydrogen peroxide and relieves oxidative stress in patients with vitiligo. Since vitiligo can cause eyelashes to turn white, the same process is believed to be involved in hair on the head (and elsewhere) due to aging. [12] [ unreliable source? ]

Stress

Anecdotes report that stress, both chronic and acute, may induce achromotrichia earlier in individuals than it otherwise would have. [13] Proponents point to survivors of disasters, such as Titanic survivor Harold Bride and prisoner of war John McCain, as well as high-level politicians such as Bill Clinton and Barack Obama. There is some evidence for chronic stress causing premature achromotrichia, [14] but no definite link has been established. It is known that the stress hormone cortisol accumulates in human hair over time, but whether this has any effect on hair color has not yet been resolved. [15] A 2020 paper, published in the journal Nature reported that stress can cause hair to lose its pigment. An overactive immune response can destroy melanocytes and melanocyte stem cells in black-haired rats. When intentionally subjecting them to panic, they bleached their coat. The next time the rats' coat grew, there were no melanocyte stem cells in these damaged follicles, so white hairs sprouted, and the color loss was permanent. [16]

UV damage

Excessive exposure to the sun is the most common cause of structural damage of the hair shaft. Photochemical hair damage encompasses hair protein degradation and loss, as well as hair pigment deterioration [17] Photobleaching is common among people with European ancestry. Around 72 percent of customers who agreed to be involved in a study and have European ancestry reported in a recent 23andMe research that the sun lightens their hair. The company also have identified 48 genetic markers that may influence hair photobleaching. [18]

Medical conditions

Albinism is a genetic abnormality in which little or no pigment is found in human hair, eyes, and skin. The hair is often white or pale blond. However, it can be red, darker blond, light brown, or rarely, even dark brown.

Vitiligo is a patchy loss of hair and skin color that may occur as the result of an auto-immune disease. In a preliminary 2013 study, researchers treated the buildup of hydrogen peroxide which causes this with a light-activated pseudo-catalase. This produced significant media coverage that further investigation may someday lead to a general non-dye treatment for grey hair. [19]

Malnutrition is also known to cause hair to become lighter, thinner, and more brittle. Dark hair may turn reddish or blondish due to the decreased production of melanin. The condition is reversible with proper nutrition.

Werner syndrome and pernicious anemia can also cause premature greying.

A 2005 uncontrolled study demonstrated that people 50–70 years of age with dark eyebrows but grey hair are significantly more likely to have type II diabetes than those with both grey eyebrows and hair. [20]

Artificial factors

A 1996 British Medical Journal study found that tobacco smoking may cause premature greying. Smokers were found to be four times more likely to begin greying prematurely, compared to nonsmokers. [21]

Grey hair may temporarily darken after inflammatory processes, after electron-beam-induced alopecia, and after some chemotherapy regimens. Much remains to be learned about the physiology of human greying. [22]

There are no special diets, nutritional supplements, vitamins, or proteins that have been proven to slow, stop, or in any way affect the greying process, although many have been marketed over the years. However, French scientists treating leukemia patients with imatinib, a drug used in treating cancer, noted an unexpected side effect: some of the patients' hair color was restored to their pre-grey color. [23]

Changes after death

The hair color of buried bodies can change. Hair contains a mixture of black-brown eumelanin and red-yellow pheomelanin. Eumelanin is less chemically stable than pheomelanin and breaks down faster when oxidized. The color of hair changes faster under extreme conditions. It changes more slowly under dry oxidizing conditions (such as in burials in sand or in ice) than under wet reducing conditions (such as burials in wood or plaster coffins). [24]

Management

The anti-cancer drug imatinib has recently been shown to reverse the greying process. [25] However, it is expensive and has potentially severe and deadly side effects, so it is not practical to use to alter a person's hair color. Nevertheless, if the mechanism of action of imatinib on melanocyte stem cells can be discovered, it is possible that a safer and less expensive substitute drug might someday be developed. It is not yet known whether imatinib has an effect on catalase, or if its reversal of the greying process is due to something else. [23]

See also

Related Research Articles

<span class="mw-page-title-main">Human skin color</span>

Human skin color ranges from the darkest brown to the lightest hues. Differences in skin color among individuals is caused by variation in pigmentation, which is the result of genetics, exposure to the sun, disorders, or some combination thereof. Differences across populations evolved through natural selection or sexual selection, because of social norms and differences in environment, as well as regulations of the biochemical effects of ultraviolet radiation penetrating the skin.

<span class="mw-page-title-main">Melanin</span> Group of natural pigments found in most organisms

Melanin consist of oligomers or polymers arranged in a manner which among other functions provide the pigments of many organisms. Melanin pigments are produced in a specialized group of cells known as melanocytes. They have been described as "among the last remaining biological frontiers with the unknown".

<span class="mw-page-title-main">Melanocyte</span> Melanin-producing cells of the skin

Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer of the skin's epidermis, the middle layer of the eye, the inner ear, vaginal epithelium, meninges, bones, and heart. Melanin is a dark pigment primarily responsible for skin color. Once synthesized, melanin is contained in special organelles called melanosomes which can be transported to nearby keratinocytes to induce pigmentation. Thus darker skin tones have more melanosomes present than lighter skin tones. Functionally, melanin serves as protection against UV radiation. Melanocytes also have a role in the immune system.

<span class="mw-page-title-main">Human hair color</span> Pigmentation of human hair follicles

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 tone of the hair is dependent on the ratio of black or brown eumelanin to yellow or red pheomelanin. Levels of melanin can vary over time causing a person's hair color to change, and it is possible to have hair follicles of more than one color on the same person. Some hair colors are associated with some ethnic groups due to observed higher frequency of particular hair color within their geographical region, e.g. straight dark hair amongst East Asians, Southeast Asians, Polynesians, Central Asians and Native Americans, a large variety of dark, fair, curly, straight, wavy and bushy hair amongst Europeans, West Asians, Central Asians and North Africans, curly, dark, and uniquely helical hair with Sub Saharan Africans, whilst gray, white or "silver" hair is often associated with age.

<span class="mw-page-title-main">Grey</span> Intermediate color between black and white

Grey or gray is an intermediate color between black and white. It is a neutral or achromatic color, meaning literally that it is "without color", because it can be composed of black and white. It is the color of a cloud-covered sky, of ash, and of lead.

<span class="mw-page-title-main">Hypopigmentation</span> Area of skin becoming lighter than the baseline skin color

Hypopigmentation is characterized specifically as an area of skin becoming lighter than the baseline skin color, but not completely devoid of pigment. This is not to be confused with depigmentation, which is characterized as the absence of all pigment. It is caused by melanocyte or melanin depletion, or a decrease in the amino acid tyrosine, which is used by melanocytes to make melanin. Some common genetic causes include mutations in the tyrosinase gene or OCA2 gene. As melanin pigments tend to be in the skin, eye, and hair, these are the commonly affected areas in those with hypopigmentation.

<span class="mw-page-title-main">Equine coat color genetics</span> Genetics behind the equine coat color

Equine coat color genetics determine a horse's coat color. Many colors are possible, but all variations are produced by changes in only a few genes. Bay is the most common color of horse, followed by black and chestnut. A change at the agouti locus is capable of turning bay to black, while a mutation at the extension locus can turn bay or black to chestnut.

PUVA is an ultraviolet light therapy treatment for skin diseases: vitiligo, eczema, psoriasis, graft-versus-host disease, mycosis fungoides, large plaque parapsoriasis, and cutaneous T-cell lymphoma, using the sensitizing effects of the drug psoralen. The psoralen is applied or taken orally to sensitize the skin, then the skin is exposed to UVA.

<span class="mw-page-title-main">Leucism</span> Partial loss of pigmentation in an animal

Leucism is a wide variety of conditions that result in partial loss of pigmentation in an animal—causing white, pale, or patchy coloration of the skin, hair, feathers, scales, or cuticles, but not the eyes. It is occasionally spelled leukism. Some genetic conditions that result in a "leucistic" appearance include piebaldism, Waardenburg syndrome, vitiligo, Chédiak–Higashi syndrome, flavism, isabellinism, xanthochromism, axanthism, amelanism, and melanophilin mutations. Pale patches of skin, feathers, or fur can also result from injury.

<span class="mw-page-title-main">Skin whitening</span> Practice of using chemical substances to lighten the skin

Skin whitening, also known as skin lightening and skin bleaching, is the practice of using chemical substances in an attempt to lighten the skin or provide an even skin color by reducing the melanin concentration in the skin. Several chemicals have been shown to be effective in skin whitening, while some have proven to be toxic or have questionable safety profiles. This includes mercury compounds which may cause neurological problems and kidney problems.

<span class="mw-page-title-main">Piebaldism</span> Medical condition

Piebaldism refers to the absence of mature melanin-forming cells (melanocytes) in certain areas of the skin and hair. It is a rare autosomal dominant disorder of melanocyte development. Common characteristics include a congenital white forelock, scattered normal pigmented and hypopigmented macules and a triangular shaped depigmented patch on the forehead. There is nevertheless great variation in the degree and pattern of presentation, even within affected families. In some cases, piebaldism occurs together with severe developmental problems, as in Waardenburg syndrome and Hirschsprung's disease.

<span class="mw-page-title-main">White horse</span> Horse coat color

A white horse is born predominantly white and stays white throughout its life. A white horse has mostly pink skin under its hair coat, and may have brown, blue, or hazel eyes. "True white" horses, especially those that carry one of the dominant white (W) genes, are rare. Most horses that are commonly referred to as "white" are actually "gray" horses whose hair coats are completely white. Gray horses may be born of any color and their hairs gradually turn white as time goes by and take on a white appearance. Nearly all gray horses have dark skin, except under any white markings present at birth. Skin color is the most common method for an observer to distinguish between mature white and gray horses.

<span class="mw-page-title-main">Poliosis</span> Medical condition

Poliosis is the decrease or absence of melanin in head hair, eyebrows, eyelashes, or any other hirsute area. It is popularly known as white forelock when it affects hair directly above the forehead.

<span class="mw-page-title-main">Amelanism</span> Pigmentation abnormality

Amelanism is a pigmentation abnormality characterized by the lack of pigments called melanins, commonly associated with a genetic loss of tyrosinase function. Amelanism can affect fish, amphibians, reptiles, birds, and mammals including humans. The appearance of an amelanistic animal depends on the remaining non-melanin pigments. The opposite of amelanism is melanism, a higher percentage of melanin.

Canities subita, also called Marie Antoinette syndrome or Thomas More syndrome, is an alleged condition of hair turning white overnight due to stress or trauma. The trivial names come from specific cases in history including that of Queen Marie Antoinette of France whose hair was noted as having turned stark white overnight after her capture following the ill-fated flight to Varennes during the French Revolution. An older case of Sir Thomas More's hair turning white the night before his beheading has also been recorded. Although a number of cases of rapid hair greying have been documented, the underlying patho-physiological changes have not been sufficiently studied.

Sex-linked barring is a plumage pattern on individual feathers in chickens, which is characterized by alternating pigmented and apigmented bars. The pigmented bar can either contain red pigment (phaeomelanin) or black pigment (eumelanin) whereas the apigmented bar is always white. The locus is therefore often referred to as an ‘eumelanin diluter’ or ‘melanin disruptor’. Typical sex-linked barred breeds include the Barred Plymouth Rock, Delaware, Old English Crele Games as well as Coucou de Renne.

Premature greying of hair (PGH), also known as canities, is the process of greying of hair occurring at an unusually early age. It 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, before 25 years in Asians, and before 30 years in Africans.

<span class="mw-page-title-main">Rhododendrol</span> Chemical compound

Rhododendrol (RD) also called 4-[(3R)-3-hydroxybutyl]phenol (systemic name), is an organic compound with the formula C10H14O2. It is a naturally occurring ingredient present in many plants, such as the Rhododendron. The phenolic compound was first developed in 2010 as a tyrosinase inhibitor for skin-lightening cosmetics. In 2013, after rhododendrol reportedly caused skin depigmentation in consumers using RD-containing skin-brightening cosmetics, the cosmetics were withdrawn from the market. The skin condition, caused by RD, is called RD-induced leukoderma. Rhododendrol exerts melanocyte cytotoxicity via a tyrosinase-dependent mechanism. It has been shown to impair the normal proliferation of melanocytes through reactive oxygen species-dependent activation of GADD45. It is now well established that rhododendrol is a potent tyrosinase inhibitor.

Autoimmune skin diseases in dogs are diseases occurring in dogs in which the immune system targets itself, with white blood cells or antibodies in the body attacking its own tissues or the extracellular protein of the skin. When autoimmune diseases occur in dogs, detection is not noted until visible, compared to humans who can verbally express their concerns. Genetics, nutrition, and external environmental factors collectively contribute to increasing the probability of an autoimmune disease developing. For dogs diagnosed with an autoimmune disease, a veterinarian's care is necessary to manage the condition. The severity varies on the type of disease the dog has and the specific symptoms. Unfortunately, there is not always a guaranteed cure, but treatments can be offered to provide comfort.

<span class="mw-page-title-main">Desmond Tobin</span> Irish academic, researcher and author

Desmond John Tobin is an Irish academic, researcher and author. He is a Full Professor of Dermatological Science at University College Dublin and the Director of the Charles Institute of Dermatology. He was Chair of British Society for Investigative Dermatology from 2018 to 2020. Tobin is a fellow of The Royal College of Pathologists, of the Higher Education Academy, of the Royal Society of Biology, Institute of Biomedical Science, and of the Institute of Trichologists.

References

  1. ↑ Pandhi, D; Khanna, D (2013). "Premature graying of hair". Indian Journal of Dermatology, Venereology and Leprology. 79 (5): 641–53. doi: 10.4103/0378-6323.116733 . PMID   23974581.
  2. ↑ 鼻毛にも白髪は生えるの？ (in Japanese). Retrieved 3 July 2012.
  3. ↑ Copping, Jasper (30 September 2012). "Grey hair 'less prevalent than previously thought'" . The Telegraph. Archived from the original on 2022-01-12. Retrieved 22 January 2017.
  4. ↑ Giana, Bosa. "What Causes Hair To Go White? Let Us Find The Exact Reasons". gaizupath.com. Retrieved 16 February 2017.
  5. ↑ Ralph M Trüeb (Jan–Jun 2009). "Oxidative Stress in Ageing of Hair". Int J Trichology. 1 (1): 6–14. doi: 10.4103/0974-7753.51923 . PMC   2929555 . PMID   20805969.
  6. ↑ Slominski A, Paus R. Melanogenesis is coupled to murine anagen: Toward new concepts for the role of melanocytes and the regulation of melanogenesis in hair growth. J Invest Dermatol. 1993;101:90S–7S
  7. ↑ "Research yields clues to why hair turns gray". Associated Press. Retrieved 5 August 2011.
  8. ↑ Storrs, Carina (1 March 2016). "First gray hair gene found, plucked out of research". CNN.
  9. ↑ Juangbhanich C; Nitidanhaprabhas P; Sirimachan S; Areekul S; Tanphaichitr VS (June 1991). "Vitamin B12 deficiency: report of a childhood case". J Med Assoc Thai. 74 (6): 348–54. PMID   1744541.
  10. ↑ Weir, Sarah B. (2012-10-02). "Why does hair turn grey?". Yahoo! Lifestyle UK. Archived from the original on 2012-10-07. Retrieved 2012-11-10.
  11. ↑ James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology (10th ed.). Saunders. ISBN   978-0-7216-2921-6.
  12. ↑ Nsikan Akpan (3 May 2013). "Cure For Gray Hair Is Almost Here, Vitiligo Study Claims". Medical Daily . Retrieved 17 January 2016.
  13. ↑ Saling, Joseph. "The Effects of Stress on Your Hair". Web MD. Retrieved 14 August 2013.
  14. ↑ Ballantyne, Coco. "Fact or Fiction?: Stress Causes Grey Hair". Scientific American. Retrieved 14 August 2013.
  15. ↑ Robert Preidt (17 Apr 2013). "Seriously Stressed? Hair Analysis Tells All, Study Finds". WebMD.
  16. ↑ Popular Science, January 1, 2020
  17. ↑ Sebetić, Klaudija; Sjerobabski Masnec, Ines; Cavka, Vlatka; Biljan, Darko; Krolo, Ivan (October 2008). "UV damage of the hair". Collegium Antropologicum. 32 (Suppl 2): 163–165. ISSN   0350-6134. PMID   19138021.
  18. ↑ 23andMe. "Hair Lightening from the Sun - 23andMe". www.23andme.com. Retrieved 2020-01-08.{{cite web}}: CS1 maint: numeric names: authors list (link)
  19. ↑ Bazian (7 May 2013). "No evidence of cure to prevent hair going grey". Filey and Hunmanby Mercury.
  20. ↑ Department of Dermatology, Academic Teaching Hospital Dresden-Friedrichstadt (14 December 2005). "Eyebrow color in diabetics". Acta Dermatovenerol Alp Panonica Adriat. 14 (4): 157–60. PMID   16435045.
  21. ↑ Mosley JG, Gibbs AC (1996). "Premature grey hair and hair loss among smokers: a new opportunity for health education?". BMJ. 313 (7072): 1616. doi:10.1136/bmj.313.7072.1616. PMC   2359122 . PMID   8991008.
  22. ↑ Cline DJ (April 1988). "Changes in hair color". Dermatol Clin. 6 (2): 295–303. doi:10.1016/S0733-8635(18)30675-2. PMID   3288386.
  23. 1 2 "Cancer drug restores hair colour". BBC News. 2002-08-08.
  24. ↑ "Interactive Dig Hierakonpolis - Archaeological Hair". Archaeology.org. Retrieved 2012-04-03.
  25. ↑ Etienne, Gabriel; Cony-Makhoul, Pascale; Mahon, François-Xavier (8 August 2002). "Imatinib Mesylate and Gray Hair". New England Journal of Medicine. 347 (6): 446. doi: 10.1056/NEJM200208083470614 . PMID   12167692.
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