Does mountain dew hurt sperm cells? if so how?

Uncertain: n one Danish study men who drank more than 1 liter of soda per day averaged 35 million sperm/ml of semen - those who did not drink soda averaged 50 million sperm/ ml. However, due to lifestyle differences it is not known if soda was causative. I don't know which types of soda these men drank. http://www.dailymail.co.uk/health/article-1262759/Drinking-cola-lower-mens-sperm-count.html

No: I say it's just silly. Dr. Fowler has pointed out that studies showing correlations do not prove causation. It may simply be that guys who drink more mountain dew prefer tighter underwear or rub it out more often (prevents sperms from getting concentrated). Bad epidemology studies generate a huge amount of junk, and if it doesn't make sense (as here), it never turns out to be true.