For someone who hasn’t acquired much knowledge about hair loss, a deficiency of certain vitamins and minerals seems to be the first suspicion as the cause of hair loss since so many advertisements and magazine articles say so.
But is it really true? Do nutritional supplements play a big role in hair loss, and if yes, how to know what supplement to choose when you have hair loss?
Do nutritional supplements really work against hair loss?
Nutritional supplements are a giant and dynamic industry. As a dermatologist, I get several inquiries from patients asking if they are effective, and if yes, how to choose one.
Macronutrients and micronutrients play an important role in the maintenance of hair growth from the follicles by affecting the division of cells. A deficiency of specific nutrients can affect the rate of hair growth, the structure of hair and move the hair into the shedding phase of the cycle.
Nutritional supplements have a major role in only a certain kind of hair loss, namely telogen effluvium, where the hair in the growing anagen phase is pushed into the shedding telogen phase.
Telogen effluvium causes an increase in diffuse hair loss from the scalp over a period of weeks to months. In the presence of a nutritional deficiency, telogen effluvium persists commonly for more than 6 months and until the deficiency is corrected.
Nutritional supplementation plays a huge role here, but only when it is established which mineral or vitamin needs to be substituted. In case no definite cause can be found, a complex nutritional supplementation may be considered.
In genetic and hormonal pattern hair loss, called androgenetic alopecia, nutritional supplements play no role in promoting hair growth or preventing hair loss. However, if someone with androgenetic alopecia experiences a sudden increase in hair loss, it is advisable to rule out nutritional deficiencies.
In special kinds of hair loss, like alopecia areata, which has an autoimmune cause, some supplements have been shown to play a minor role. However, it is still not established conclusively and currently holds no place in the treatment of this hair loss condition.
Let’s examine in detail which nutrients can cause hair loss or worsen the existing hair loss, and thus make the supplementation necessary.
Vitamins for hair loss
Let us see supplementation of which vitamin(s) could actually benefit in hair loss.
It is known that Vitamin A activates hair follicle stem cells, and Vitamin A is needed for the hair follicle to function optimally. However, there is no evidence that a deficiency of Vitamin A could cause hair loss.
On the contrary, an excess of vitamin A, either in the food or as a supplementation, could result in hair loss . One study in mice even found that reduction of Vitamin A in the diet could actually delay the onset of hair loss .
Vitamin B2 or riboflavin plays a very important role in energy production in the body. A deficiency of Vitamin B2, although very rare, can cause hair loss . Food sources of vitamin B2 include eggs, milk, meat, etc.
Vitamin B7 or biotin is also known as vitamin H. The H here stands for hair, and biotin gets its name from (supposedly) playing such an important role in hair loss. In most hair loss supplements, biotin is to be found.
Even many dermatologists prescribe biotin as an empirical treatment when the cause of hair loss is difficult to ascertain. However, there is hardly any evidence that biotin helps against hair loss in people who are not biotin deficient. And biotin deficiency is pretty rare.
Biotin deficiency can be genetic or acquired . Certain medicines like anti-epilepsy drugs, intestinal malabsorption, pregnancy, alcoholism, or raw egg consumption could predispose someone to develop biotin deficiency.
Biotin deficiency rarely manifests as only hair loss; brittle nails and skin rashes almost always accompany it. Unless there is an established biotin deficiency or a risk factor that can cause biotin deficiency, a blanket treatment with biotin is not recommended for hair loss.
Vitamin B6 and Vitamin B12
Vitamin B6 or folic acid, along with vitamin B12, plays a role in cell division in the hair follicle. In multiple studies, no difference in the blood levels of folic acid and Vitamin B12 has been found in the patients with hair loss, suggesting that supplementation is not necessary in telogen effluvium and alopecia areata cases .
Vitamin C is not associated with hair loss, but in iron deficiency-induced hair loss, supplementation of Vitamin C is recommended to increase iron absorption in the intestine. Thus, if a low intake of Vitamin C is suspected in an iron-deficient person, only then a supplementation makes sense.
A small-scale study of females with telogen effluvium and androgenetic alopecia showed a lower level of vitamin D in the hair loss group as compared to the control group .
Similarly, lower vitamin D levels have also been observed in alopecia areata. Even though large-scale studies are lacking, it is advisable to screen Vitamin D in hair loss patients and supplement them in case of deficiency .
Minimal evidence exists supporting vitamin E supplementation and hair growth. A study showed a lower level of vitamin E in patients with alopecia areata, but other studies have subsequently disproved it.
In fact, excess vitamin E supplementation leads to hypervitaminosis E, which could cause an increase in hair shedding . Unless medically indicated in other deficiency cases, Vitamin E supplementation is not recommended.
Minerals and micronutrients for hair loss
Deficiency of minerals is a much more common cause of hair loss than vitamins. Let us break down which minerals play an important role in hair growth.
The most common nutritional deficiency which causes hair loss, especially in women, is iron . Every female hair loss should be investigated for iron deficiency. A more sensitive marker for testing iron deficiency anemia is ferritin, the iron reserve protein.
In case of iron deficiency, the body diverts the iron needed for hair to maintain the body reserves, hence triggering a telogen effluvium. Even if the iron or ferritin level is in the low range of normal, supplementation improves hair loss.
The body cannot generate zinc on its own, and thus all the body’s zinc requirements are fulfilled by external sources. Zinc deficiency is associated with telogen effluvium, and low levels of zinc can be found in alopecia areata patients’ blood.
A study with 312 hair loss patients, with 30 healthy controls, revealed a strong association of zinc deficiency with hair loss .
Even though selenium is in many hair supplements, the only credible evidence of selenium supplementation is hair loss in chemotherapy patients, and ingesting selenium has demonstrated no benefit in hair loss in otherwise healthy people .
On the other hand, Selenium toxicity is strongly associated with hair loss, and thus an indiscriminate supplementation should be avoided.
Copper deficiency does not directly cause hair loss. It may result in brittle hair and increased breakage resulting in the illusion of hair loss.
This deficiency is rare and not considered primarily when an adult presents with hair breakage or hair loss. Thus, supplementation is not effective either.
Other supplements for hair loss
Apart from vitamins and minerals, other supplements may also come into play when it comes to hair loss:
Essential fatty acids
Deficiency of essential fatty acids like omega-3 and omega 6 can cause hair loss. These fatty acids may also influence androgen action by 5 alpha-reductase inhibition, similar to the drug oral or topical finasteride, and play a small role in androgenetic alopecia.
Essential fatty acids like arachidonic acid also promote hair growth by prolonging the anagen (growth) phase .
Amino acids play a vital role in hair health. Oral L-cysteine, combined with other micronutrients and minerals, has been shown to prolong the anagen phase and increase the hair density in Telogen effluvium .
Another combination supplement containing Lysine with iron, B12, Vitamin C, and biotin resulted in a 39% reduction in hair shedding in women who had previously no success with iron supplementation alone.
Since it is also an alpha-reductase blocker, saw palmetto is regarded as a natural alternative to finasteride. Many studies in mice have shown evidence of hair growth with saw palmetto supplementation, but in humans, a good study proving that is still lacking.
Even though some hair growth level has been documented in androgenetic alopecia, it is still significantly inferior to finasteride. A hundred men with AGA were treated with 320 mg of oral saw palmetto extract or 1 mg of oral finasteride daily for 2 years. 68% of patients experienced hair growth in the finasteride group, as compared to 38% in the saw palmetto group .
Even though the action mechanism is unclear, saw palmetto has also shown some promise in telogen effluvium, but large-scale data is still missing.
Marine proteins have recently gained a lot of interest in hair growth supplements.
Marine proteins in multiple studies have shown a potential to increase the hair growth and hair thickness by thickening the vellus hair diameter, as well as a reduction in the shedding resulting in an increase in total hair count and total hair density with minimum to no reported side effects .
It can be used as a complementary therapy in both telogen effluvium and androgenetic alopecia in males and females.
A word of caution: aimless supplementation could be dangerous
Hair supplements do not require a doctor’s prescription. But make sure you are consulting a doctor for a deficiency check and diagnosis before you decide which supplements to take. Indiscriminate supplementation could be expensive, useless, and sometimes even dangerous. For example:
There are reports of selenium toxicity following intake of hair supplements . Selenium toxicity can result in hair loss, memory problems, gastrointestinal symptoms, and skin blistering.
Biotin supplementation for hair loss is most widespread, and most have the notion that biotin since it is water-soluble, is a harmless supplement. This is unfortunately not the case.
An FDA warning says that biotin supplements could interfere with your blood results. It could cause blood to show low troponin levels, which is a marker of a heart attack and can delay the diagnosis and management.
Biotin could even cause misdiagnosis of thyroid disorders due to altered thyroid hormones in the blood. If you have planned a thyroid test, make sure to skip your biotin supplements at least 3 days before the test, especially if you are taking more than 10 mg a day.
Biotin can also alter the hCG levels in blood and urine and may result in a false negative pregnancy test.
Excessive intake of Vitamin A and E can also result in increased hair loss.
There are reports of hormonal side effects with saw palmetto, although rarer and less in intensity than finasteride, like enlargement of breasts in males, loss of libido, etc. Saw palmetto could reduce the prostate cancer marker levels in the blood, resulting in a delay in the diagnosis.
Navigating through the huge market of hair supplements may not be easy. But the good news is, you do not need to. Unless a deficiency is suspected or proven in blood tests, nutritional supplements would hardly cure your hair loss. Some supplements like marine proteins or fatty acids may play a supportive role, but they are in no way a substitute for primary therapy.
Indiscriminate supplementation comes with its own risks of side effects and is thus highly discouraged. If you consider boosting your hair loss therapy with a nutritional supplement, speak to a doctor first to choose the right one for you.