Sweat glands play an important roll in how skin heals from injury, but they don’t work as well in seniors, say University of Michigan researchers.

Their study, published in Aging Cell, compared the skin of 18 elderly patients to that of 18 young adults, all of whom were given skin lesions smaller than a pencil eraser while under local anesthesia.

For the first time, the team of scientists and dermatologists were able to pinpoint the cellular mechanism that makes older skin slower to regenerate.

Eccrine sweat glands are found throughout the body and help create new skin cells after injury. The researchers wanted to determine if seniors — who typically sweat less — would get less help from those specific sweat glands.

They found seniors had fewer active sweat glands and they are grouped farther apart, resulting in a thinner epidermis and delayed wound closure.

Lead author Laure Rittié, Ph.D., said the same processes that lead to wrinkling and sagging are at play in weakened sweat gland infrastructure. Sun damage is one of the main culprits, she noted. 

Efforts to limit skin damage during aging will help limit aging’s negative impact on wound repair, Rittié added.