Vitamin E against hair loss?

The vitamin E is a family of eight fat-soluble molecules, comprising four tocopherols and four tocotrienols. Not produced by the human body, it is naturally synthesised by algae, plants and certain fungi. Therefore, it can be found in food derived from plant sources but also in animal products that consume plants. The vitamin E is also included in the composition of several cosmetics, intended for both skin and hair. Regarding its hair benefits, there are reasons to believe that this active ingredient can limit hair loss.

Indeed, a study conducted in 2010 involving 38 individuals experiencing varying degrees of hair loss highlighted the densifying effects of Vitamin E. Over a period of 8 months, these volunteers took a capsule twice a day: a placebo for half of them and Vitamin E for the others (50 mg of tocotrienols and 15.43 mg of alpha-tocopherol). A significant increase in hair count was observed following the intake of Vitamin E, while no difference was noted among the volunteers who received the placebo. The results are presented in the table below.

Note : Despite these encouraging results, it is important to remain cautious about the effects of vitamin E on hair loss. It would be beneficial if more studies involving a greater number of volunteers could confirm these effects.

Various mechanisms of action of Vitamin E can explain its effects on hair growth and loss :

• Vitamin E protects hair follicles from oxidative stress.

  Several recent studies have highlighted a harmful effect of oxidative stress on hair growth. A team of researchers has notably demonstrated that free radicals, and more specifically lipid peroxides, accelerate the transition between the anagen phase, or growth phase, and the catagen phase, or rest phase of the hair cycle. Free radicals also induce apoptosis of keratinocytes, the cells of the hair follicle, which precipitates hair loss.

  Thanks to its antioxidant properties, vitamin E can protect hair follicles from damage caused by oxidative stress. Indeed, the aromatic cycle present in its chemical structure allows it to donate an electron to free radicals, thereby stabilising them. In doing so, vitamin E can help to prevent hair loss.

• Vitamin E prevents inflammation of the hair follicles.

  If not controlled, oxidative stress can trigger inflammatory phenomena in hair follicles, which also contribute to hair loss. Indeed, keratinocytes can respond to oxidative stress caused by UV rays, pollutants, and irritants by producing nitric oxide and particularly by releasing interleukin-1α (IL-1α). Furthermore, free radicals can activate certain nuclear factors, such as the AP-1 transcription factor, involved in the release of other cytokines. Studies in vitro have shown that these inflammatory molecules inhibit the growth of hair follicles.

  The vitamin E, due to its anti-inflammatory properties, can limit these processes. Several scientific studies have focused on its mechanisms of action and have shown that this active ingredient can suppress the NF-κB and JAK-STAT6 signalling pathways. These are major transcriptional factors in mediating the inflammatory response and in the expression of cytokines and chemokines.

• Vitamin E supports the delivery of nutrients to the hair follicle.

  Efficient blood circulation in the scalp is necessary for hair growth. Indeed, the keratinocytes present in the hair follicles require nutrients and oxygen carried by the blood to synthesise keratin and assemble to form the hair shaft. Moreover, the removal of waste from the hair bulb, preventing potential obstructions of the follicles, could not occur without good blood circulation.

  The vitamin E also plays a role in blood circulation and optimises it through its vasodilatory properties. Tocopherols, in particular, work by increasing the production of nitric oxide (NO) by the endothelial cells of the blood vessels. NO induces a relaxation of the smooth muscles of the vessels, which promotes blood flow. Vitamin E also inhibits the release of thromboxane A2 (TXA2) by platelets, which are vasoconstrictors that induce platelet aggregation.

• PANGANAMALA R. V. & co. Modulation of platelet thromboxane A2 and arterial prostacyclin by dietary vitamin E. Prostaglandins (1981).

• JIALAL I. & al. Vitamin E, Oxidative Stress and Inflammation. Annual Review of Nutrition (2005).

• TRUEB R. M. Oxidative Stress in Hair Ageing. International Journal of Trichology (2009).

• HAY Y. K. & al. Effects of Tocotrienol Supplementation on Hair Growth in Human Volunteers. Tropical Life Sciences Research (2010).

• TRUEB R. M. The impact of oxidative stress on hair. International Journal of Cosmetic Science (2015).