Where have all the vegans gone?

A natural chemical found in soy, tofu and legumes can potentially damage sperm and lower men's fertility, Reuters reports of new research from King's College London.

The plant chemical, genistein, mimics the effect of the female hormone estrogen and in turn affects sperm in laboratory mice. Tests in humans have shown an even stronger impact than in the rodents. Research leader Lynn Fraser found in lab tests that small amounts of genistein can cause human sperm to "burn out" and lose fertility, reports Reuters.

And it's not just men who should avoid eating soy, tofu, and legumes. Women who are trying to conceive a baby should also avoid it since the chemical can affect sperm when it is in the female preparing to fertilize an egg. "Maternal exposure to the compounds is probably more important than paternal exposure," Fraser told a meeting of the European Society of Human Reproduction and Embryology meeting.