PSA: Despite what the athletic and “athleisure” wear industry wants you to believe, underwear made from synthetic fibers is not good for your nether regions. This includes rayon, polyester, and so-called bamboo.
There’s a reason why doctors recommend cotton underwear, and that goes for men as well as women. Contrary to the “wicking” claims made on labels and in marketing materials, synthetic fibers are less breathable and increase risk of yeast and other infections.