By Susan Biali, M.D.

I’ve written frequently about my stressful stint, years ago, in an Emergency Medicine Residency program.   I’ve described some of the effects that that stress had on me and my body, including depression, colds, and a kind of dental infection that famously for affected stressed out World War I soldiers.  However, I never mentioned the fact that, to top it off, my hair also became noticeably thinner.  For those of you who’ve never experienced this, I urge you to be compassionate with people you know who complain of or suspect hair loss.  This may not seem like a big issue when compared to cancer, war or famine, but it can be deeply upsetting and a source of much worry and insecurity.  

Thanks to my own wonderful doctor, a visit to a specialty Hair Clinic, and a major lifestyle change, my hair’s looking pretty good now.  Yet ever since, I’ve been more aware of supplements claiming to improve hair quality and growth.  Do any of them work?

Surfing the net, I came across websites listing nutrients “essential” to healthy hair.  However, this turned out to be one of the most difficult topics I’ve ever researched, as I consistently turned up websites promoting product sales, rather than evidence-based information in the form of scientific literature.   Medline and PubMed searches turned up very little; the research information I’ll share with you today took a lot of work to find!

Commercial websites mention B vitamins, particularly niacin and pantothenic acid, as critical to hair health.  I couldn’t find any official reference supporting these functions, other than the fact that niacin is important to skin health.  Others also mentioned folic acid and B6 as important nutrients for hair; again, I wasn’t able to find literature supporting this.
A dermatologist once recommended I take daily biotin, and I still do.  I did uncover a proven relationship between this B vitamin and your hair.  Biotin deficiency causes fine and brittle hair, and subsequent hair loss, but there’s a catch: true deficiency is exceptionally rare.  According to Columbia University dermatologist Noah Scheinfeld, our daily biotin requirement is quite low, and almost all foods contain significant quantities.  Our intestinal flora also contribute by synthesizing biotin, and biotin molecules are even recycled by our body.

However, there are some surprising situations which might trigger biotin deficiency, and its resulting hair symptoms.  Raw egg whites, the superfood-of-choice of some bodybuilders, put them at risk for biotin deficiency.  In “egg white injury syndrome”, described by Boas in 1926, the glycoprotein avidin in raw whites actively binds biotin in the body, making it useless.   Cooking eggs destroys this troublesome compound.   The anti-convulsants phenytoin, primidone, and carbamazepine also may trigger biotin deficiency.  According to Scheinfeld, patients on these medications should take a biotin supplement.  Patients on prolonged antibiotics might also benefit from a supplement, as the drugs diminish our biotin-producing intestinal bacteria.