Micronutrients in Hair Loss

The 2018 study "Micronutrients in hair loss" reviewed 92 articles and found that certain micronutrients play a significant role in hair loss and growth. Lower levels of iron, zinc, and vitamin D were associated with telogen effluvium and alopecia areata, while androgenetic alopecia was linked to lower levels of iron and vitamin D. Both lower and increased levels of vitamin A could result in telogen effluvium, with lower levels also causing hair breakage. Vitamin C insufficiency was found to result in hair shaft abnormality. However, there was no data about hair loss associated with abnormal biotin levels. The study concluded that the role of micronutrients for hair follicle function was not completely understood and that treatments of hair loss with micronutrients without confirmed deficiencies had not shown utility.