It is National Caffeine Awareness Month and this stimulated (pun intended) me to see whether there is any convincing evidence that a strong cup of java will put hairs on your head.

Copley looked at caffeine and its role in helping aging skin, cellulite and hair growth and she noted that the evidence at that time (in 2008) was contradictory. Caffeine is believed to protect against testosterone, which shortens the hair shaft’s growth phase and the hair root’s lifespan. But, ironically, excessive oral intake of caffeine substances can increase levels of DHT in the body, stimulating production of testosterone and resulting in hair loss.

The caffeine rush seems to have been instigated by a 2006 study (published in 2007) into the effects of testosterone and caffeine. It was a small study but was at least conducted on human hair using hair follicles from 14 biopsies. The researchers (lead by a Dr Fischer based at the University of Jena) impeded their growth with testosterone and then counteracted this with caffeine in concentrations of 0.001% and 0.005%. Moreover, caffeine alone led to a significant stimulation of hair follicle growth.

Prior to this research, a 2006 study only proved that caffeine was beneficial for barrier function in male skin. This may, in turn, help follicle health, but it wasn’t terribly convincing.

Since Dr Fischer’s work, there haven’t been any other studies that I could find. This surprised me as the promise of a safe solution for male pattern baldness would encourage a lot of check books to open and fund further research.

Even if you are convinced by such a small body of evidence that caffeine will help hair grow, be warned, though. You will not encourage hair growth by extending your coffee break. The caffeine needs to be topically applied. If you are wondering whether caffeine will penetrate the hair follicles, then you’ll be comforted by German researchers who found that it did, within about two minutes.

Personally, I found the lack of new research on caffeine and hair growth a bit of wake up call. For now I am going to stick to copper peptides.