Without underwear, you don’t have any protection between the outer layer of your skin and the “harsh reality of the fabric and seams of your pants,” says Mona Gohara, M.D., an associate clinical professor of dermatology at Yale University.
Related: 6 Ways to Prevent Chafing
This can cause painful skin irritation. So before you go commando, apply a thin layer of baby powder or petroleum jelly to your groin. It’ll help form a barrier to minimize the friction, Dr. Gohara says.