Can being vegetarian affect sperm health?
There is some evidence linking diet to sperm health but there really isn’t a lot that is known for sure.
Vegetarians (especially vegans) may not get as much vitamin B12 from their diets as they need. This vitamin is important for metabolism in the body’s cells and low levels are associated with male infertility. Vitamin B12 supplements were found to have improved sperm counts and sperm quality in several studies.
Soy is a common source of protein for many vegetarians, but it is also high in compounds with oestrogen-like effects, which may affect sperm health. This was suggested as the cause of lower sperm counts and reduced sperm movement in vegetarian men compared to non-vegetarians.