Cordyceps is a fungus that lives on certain caterpillars in the high mountain regions of China. It is sometimes used as a supplement.

Most supplements use cordyceps that is made in a lab. Although cordyceps is sometimes called a mushroom, the type of cordyceps that is made in a lab does not grow a mushroom.

Cordyceps might improve immunity by stimulating cells and specific chemicals in the immune system. It might also help fight cancer cells and shrink tumor size, particularly with lung or skin cancers. Natural cordyceps is hard to get and might be expensive.

People most commonly use cordyceps for athletic performance, kidney disorders, liver problems, and sexual problems.