Eating a half serving a day of soy based foods could be enough to significantly lower a man's sperm count, according to the largest study in humans to look at the relationship between sperm quality and soy rich foods. The study found that men that consumed the highest amounts of soy foods had lower sperm count than those who did not.
The difference was said to be significant.
Researchers say just one cup of soy milk or one serving of tofu or soy burgers every other day made a difference.
Researchers also found the association between soy foods and lower sperm count was stronger in overweight men.