New research reveals that sweat struggles to pass through tattoos, which could impact on an athlete’s ability to stay cool. The dramatic increase in the popularity of tattoos over the last decade prompted scientists at Alma College, Michigan to investigate the effect of ink on sweat rates.

Tattooing involves permanently depositing ink 3mm to 5mm under the skin at a similar depth as eccrine sweat glands. These glands regulate the body’s temperature by releasing sweat as the body’s temperature
rises; the evaporation of sweat has a cooling effect and the nervous system goes to work to stimulate the eccrine glands to release sweat. Sweat is made up of water, sodium and other substances that help cool the body down.

The researchers measured sweat rates on neighbouring patches of skin, one tattooed and the other clear.

“The mean sweat rate from tattooed skin was significantly less than non-tattooed skin,” said their report in the journal Medicine and Science in Sports and Exercise.

While the sweat rate for clear skin averaged 0.35mg per centimetre per minute, the equivalent figure for tattooed skin was just 0.18mg/cm/min.

“All 10 participants generated less sweat from tattooed skin than non-tattooed skin,” said the report.

Image by Shutterstock