1, chemical fiber underwear can lead to poor sperm quality. If men have the habit of wearing chemical fiber underwear, it is likely to cause the problem of male oligospermia and affect normal fertility. The sperm count of men wearing pure polyester underwear decreased significantly from 40% to 14 months, and that of men wearing semi-cotton and semi-polyester blended underwear decreased from about 9% to 10 months. 2, pure cotton underwear is easy to cause skin diseases For men who sweat a lot and often need to drive, the texture of underwear must be chosen with good sweat absorption and high permeability. Although cotton underwear has good sweat absorption effect, it is not easy to dry, which may easily lead to humid and sultry local environment, easy to breed bacteria, and may also lead to skin diseases such as pudendal redness and itching. Therefore, men with this demand must pay attention to the texture of underwear. 3. Tight underwear causes male diseases such as penis bending, scrotum dampness and eczema. Men who often wear tight underwear will cause penis deformation and bend to varying degrees. But also can cause scrotal dampness, eczema and other male diseases. Therefore, men should not blindly pursue personal effects when choosing underwear. More importantly, they should be comfortable and should not oppress the sexual organs too much. Through the above introduction, I believe everyone understands how important it is to buy good quality underwear, so male friends should remember to buy good quality underwear in their daily lives to avoid unnecessary trouble.