Getty/Angela Weiss
Though he recently cut his hair for a role, Jared Leto was a fan of the man bun.
When hair is pulled back into an overly tight style, it causes unnecessary strain on follicles, specifically on the front hairline, and can result in a condition called traction alopecia.
"They're putting traction on the hair follicles that the hair is not really meant to take," Dr. Sabra Sullivan, a dermatologist from Mississippi, told Mic. This pulling can cause hair follicle death and even scarring.
Dr. Sullivan adds that traction alopecia in men is becoming more common, and that hairstyles like the man bun should shoulder at least some of the blame.
Similarly tight hairstyles, like ponytails, can also cause the issue.
If you are going to wear the look, make sure to keep the bun loose, as it's really the tightness of the style that causes traction alopecia, notes Dr. Sullivan.