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Nutritional Factors and Supplements in Hair Loss

Hair is produced continuously (grows) with an average of 0.35 mm per day and shed. Hair is the fastest growing tissue in our body after bone marrow. Hair follicles that produce hair therefore require calories, proteins, trace elements and vitamins for this intense biosynthesis activity.

The lack of elements and vitamins necessary for the regular processing of energy, essentials and metabolic structure of human body will cause hair loss, trigger hair disease or make the disease resistant to treatment. Therefore, both quality and quantity of hair growth are closely related to nutrition.


Hair follicles need energy in order to rescue the high rate of mitosis. This energy is mainly provided by carbohydrates. When a low-calorie diet is received, follicle tries to supply the required energy from amino acids. Thereby, both energy and the essentials of body are reduced. Hair becomes thinner, breaks easily and it is reduced in density. Lanugo hair may increase. This can be seen in marasmus, in children and those who have low-calorie diets, especially when the daily calorie intake falls below 1000 kcal.


Proteins, called as keratin, form 80% of the chemical structure of hair. So, hair is affected in case of an incomplete intake of proteins. Hair gets dull, easily falls out and telogen effluvium is seen. Person can feel his/her hair soft, but it has lost its elasticity. Hair color might be lightened (hypochromophilia). Protein deficiency can be seen as Kwashiorkor in children. Low protein intake without malnutrition can be seen in infants who are fed with poor milk feeding, gastrointestinal diseases, anorexia nervosa, drug addicts and malignancies.


Despite the indisputable need for iron in high biosynthesis environment, the role of iron in hair loss has not been fully clarified. Sensitivity of the methods used to detect iron deficiency is especially important in hair diseases. Once patient’s iron level decreases, anemia develops at the last point. Iron, required for the construction of hemoglobin, is firstly mobilized in hair follicles. For this reason, it is possible to encounter with hair loss long before anemia occurs in blood.

Serum ferritin level is the most sensitive and specific laboratory test to demonstrate iron deficiency. In studies, ferritin levels were evaluated and 41 ng/ml level was detected to show iron deficiency with 98% sensitivity. Although there is no standardization in ferritin levels for ideal hair growth, studies have shown that telogen phase is increased when serum ferritin falls below 40 ng/ml, telogen phase is longer at 40-70 ng/ml and hair go through normal Anagen phase above 70 ng/ml.

Although every person with iron deficiency doesn’t suffer from hair loss, it is accepted that discharge of iron deposits in the genetically susceptible people cause hair shedding. Therefore, it is suggested to increase the iron deposits to the desired levels for hair loss problems.


Although zinc is the first thing come to mind among hair loss causes, there is no convincing data about the relation of zinc and hair loss. Indications of zinc deficiency include periorificial dermatitis, angular cheilitis, diarrhea and alopecia. It is not suspected from zinc deficiency when a person with normal nutrition habits has hair loss without any other symptom. Besides, there are also studies suggesting that there may be underlying zinc deficiency in long-term alopecia areata cases resistant to treatment and these patients will benefit from zinc replacement.

Zinc deficiency is seen in acrodermatitis enteropathica, a rare form of genodermatosis. Irregular bands, called as trichothiodystrophy, are monitored in the polarized microscope. Hair is thinned at this stage. If zinc support is decided to be given, it should not exceed 30 mg/day since zinc deteriorates the absorption of iron, calcium and copper and it should be taken 2 hours after iron preparats. In the presence of normal zinc level, zinc supplementation doesn’t have any additional contribution to hair growth.

Amino acids

Characteristic of the keratin, which constitutes 80% of hair, is the high sulfur content. This sulfur is derived from cystine amino acids. Cystine is known to have positive effects on hair growth. Improvement has been reported in tricogram and phototricogram results, hair quality and hair durability when cystine is given with B complex vitamins. It is thought that Vitamin B6 helps cystine diffused in hair follicles and this system contributes to hair growth by making glutathione-mediated detoxification.

L-lysine is another essential amino acid that can be important in hair growth. Since L-lysine intake is exclusively restricted to meat, fish and egg, lack consumption of these foods (e.g. vegetarians) might cause problem in hair growth. Although the role of these amino acids is not known clearly, it is accepted that lysine is necessary for zinc and iron use.


Vitamin B12 is often associated with hair loss, but it has no role recognized in hair growth.

Biotin and niacin are known to have positive effects on hair growth. Experiments conducted on animals showed that the lack of biotin causes hair shedding. However, biotin supplementation is not significant for non-deficient individuals. Biotin deficiency is a rare nutritional disorder caused by consuming raw egg.

Our doctors at Clinicana Hair Transplant Center state that vitamin D gets significantly lower in alopecia areata patients and the deficiency is correlated with the severity of disease. Vitamin D is known to play role in hair growth, differentiation and hair cycle. In this regard, we recommend our patients (especially females) to have regular tests of vitamin D and receive supplementation in case of deficiency.