The U.S. hair loss treatment industry was on track to hit $3.6 billion in 2016 and has been projected to grow from then until 2021. Further, as many as 6.8 million people in the United States have a lifetime risk for experiencing hair loss as high as 2.1%.
While the market need is certainly there, the hair loss segment has proven challenging to researchers and product developers alike. Some causes of different hair loss types are known, but the market offers only somewhat effective—or not—treatment selections. The good news is, science is beginning to unravel new facts about underlying causes.
The latest is research from the University of California, San Francisco (UCSF), showing that in animal models, regulatory T cells called Tregs, which are associated with inflammation, trigger stem cells in skin to promote healthy hair growth. Without Tregs, stem cells cannot regenerate hair follicles, which leads to baldness.
According to Michael Rosenblum, M.D., Ph.D., an assistant professor of dermatology at UCSF and senior author on the paper, hair follicles are constantly recycling, and this has been thought to be an entirely stem cell-dependent process. "But it turns out Tregs are essential. If you remove this one immune cell type, hair just doesn’t grow," he explained.
The study, published online in Cell, suggests defects in Tregs could be responsible for alopecia areata and potentially play a role in other forms of baldness. Also, since the same stem cells are responsible for helping skin to heal after injury, the study raises the possibility that Tregs may also play a key role in wound repair.
As further truths behind the roles of Tregs are discovered, it's only a matter of time for cosmetic science to put them into practice. One might even envision they could arm consumers with hair loss immunity.
