1. Many people have asked about zinc and hair growth.
2. In my studies of hair growth, I never could find any significant actions of zinc on hair growth. Some studies in mice found zinc causes alopecia.
Studies have found that ionic zinc can inhibit 5-alpha reductase (type I) but zinc has no effect on type II reductase). Some studies have found that the combination of B6, zinc salts and azelaic acid, even at low
concentrations, caused a 90% inhibition of 5-alpha reductase activity - but this is still not hair growth. In some persons zinc salts are often used in disorders related to excess DHT such as acne and prostrate
hyperplasia. The topical application of zinc has shown to reduce sebum production and acne. Some people suffering from acne have been found to have zinc deficiencies in their skin, despite of the fact that they
have normal levels within their bloodstream.
The effects of topical zinc on hair growth may be due to skin irritation actions. In the 1970's, a number of severe skin irritants, such as nitrobenzene derivatives, were investigated for hair growth properties. While
they initially stimulated hair growth, they ultimately produced unacceptable scalp damage and irritation and could not be continued for use.
Zinc salts can inhibit the action of the immune system macrophages on the skin. Since the macrophages are key cell responsible for skin repair, excessive use of zinc salts on the skin could inhibit skin and hair
follicle repair. Mulhern et al 1986 reported that excessive dietary zinc in mice reduced plasma copper and induced alopecia. Lansdown 1991 (Westminster Medical School, Department of Comparative Biology,
London, UK) examined the dermal irritancy of six zinc compounds was examined in three animal models. In open patch tests involving five daily applications, zinc chloride (1% aqueous solution) was severely
irritant in rabbit, guinea-pig and mouse tests, inducing epidermal hyperplasia and ulceration; aqueous zinc acetate (20%) was slightly less irritant. Zinc oxide (20% suspension dilute Tween 80), zinc sulphate (1%
aqueous solution) and zinc pyrithione (20% suspension) were not overtly irritant, but induced a marginal epidermal hyperplasia and increased hair growth. Thus, hair growth effects observed with zinc may be
secondary to dermal irritation. (Lansdown AB, Interspecies variations in response to topical application of selected zinc compounds, Food Chem Toxicol 1991 Jan; 29 (1): 57-64)
Like zinc, topical cortisone has been used to promote hair growth and is often reasonable effective in persons with inflammatory scalp conditions. But cortisone stops skin repair and, if used for an extended period,
ultimately thins the skin, damages hair follicles, and causes hair loss.
3. Some studies with zinc-containing hair growth systems were actually before and after hair transplants. See http://www.folligen.com/abcnews.html
4. It is possible that in some cases zinc may have an anti-inflammatory action, like cortisone, and this may help hair growth in some conditions.
5. Many people think the shampoo and conditioner improve hair growth. One spas chain licensed these products based on their tests that
found better hair growth. But the basic Folligen are much stronger.
6. Copper also inhibits 5 alpha reductase, the enzyme that makes DHT.
7. Some times increasing hair growth causes more fallout as new hair pushes out dormant hairs. This ahs been found for minoxidil and propecia at times.
Best wishes,
Loren Pickart
Skin Biology
2. In my studies of hair growth, I never could find any significant actions of zinc on hair growth. Some studies in mice found zinc causes alopecia.
Studies have found that ionic zinc can inhibit 5-alpha reductase (type I) but zinc has no effect on type II reductase). Some studies have found that the combination of B6, zinc salts and azelaic acid, even at low
concentrations, caused a 90% inhibition of 5-alpha reductase activity - but this is still not hair growth. In some persons zinc salts are often used in disorders related to excess DHT such as acne and prostrate
hyperplasia. The topical application of zinc has shown to reduce sebum production and acne. Some people suffering from acne have been found to have zinc deficiencies in their skin, despite of the fact that they
have normal levels within their bloodstream.
The effects of topical zinc on hair growth may be due to skin irritation actions. In the 1970's, a number of severe skin irritants, such as nitrobenzene derivatives, were investigated for hair growth properties. While
they initially stimulated hair growth, they ultimately produced unacceptable scalp damage and irritation and could not be continued for use.
Zinc salts can inhibit the action of the immune system macrophages on the skin. Since the macrophages are key cell responsible for skin repair, excessive use of zinc salts on the skin could inhibit skin and hair
follicle repair. Mulhern et al 1986 reported that excessive dietary zinc in mice reduced plasma copper and induced alopecia. Lansdown 1991 (Westminster Medical School, Department of Comparative Biology,
London, UK) examined the dermal irritancy of six zinc compounds was examined in three animal models. In open patch tests involving five daily applications, zinc chloride (1% aqueous solution) was severely
irritant in rabbit, guinea-pig and mouse tests, inducing epidermal hyperplasia and ulceration; aqueous zinc acetate (20%) was slightly less irritant. Zinc oxide (20% suspension dilute Tween 80), zinc sulphate (1%
aqueous solution) and zinc pyrithione (20% suspension) were not overtly irritant, but induced a marginal epidermal hyperplasia and increased hair growth. Thus, hair growth effects observed with zinc may be
secondary to dermal irritation. (Lansdown AB, Interspecies variations in response to topical application of selected zinc compounds, Food Chem Toxicol 1991 Jan; 29 (1): 57-64)
Like zinc, topical cortisone has been used to promote hair growth and is often reasonable effective in persons with inflammatory scalp conditions. But cortisone stops skin repair and, if used for an extended period,
ultimately thins the skin, damages hair follicles, and causes hair loss.
3. Some studies with zinc-containing hair growth systems were actually before and after hair transplants. See http://www.folligen.com/abcnews.html
4. It is possible that in some cases zinc may have an anti-inflammatory action, like cortisone, and this may help hair growth in some conditions.
5. Many people think the shampoo and conditioner improve hair growth. One spas chain licensed these products based on their tests that
found better hair growth. But the basic Folligen are much stronger.
6. Copper also inhibits 5 alpha reductase, the enzyme that makes DHT.
7. Some times increasing hair growth causes more fallout as new hair pushes out dormant hairs. This ahs been found for minoxidil and propecia at times.
Best wishes,
Loren Pickart
Skin Biology