What makes my pillow case turn yellow?

Pillowcases can turn yellow due to a combination of factors such as sweat, oils from your skin and hair, and the breakdown of fabric fibers over time. Additionally, exposure to sunlight and certain laundry detergents can contribute to discoloration. If you use products like hair oils or skincare items, these can also leave residues that lead to yellowing. Regular washing and using a protective pillowcase cover can help minimize this issue.