Mushrooms are full of antioxidants that may have anti aging potential Penn State University How the lowly mushroom is becoming a nutritional star For those of you asking Yes, mushrooms are the solution to old person smell, but some are better than others! Those highest in ergothioneine are: Oyster mushrooms Shiitake mushrooms The nutritional benefit of mushrooms is remarkable. For centuries, mushrooms have been legendary for their nutritional value. But it's only been recently that mushrooms have been studied and their true power revealed.