Many studies are showing a link between excess weight and male infertility. In this study, researchers combined data from 14 studies comparing sperm count in overweight, obese, and within healthy range weight men, along with data from an infertility center.
They found that overweight men were 11 percent more likely to have a low sperm count and 39 percent more likely to have no sperm in their ejaculate. Obese men were 42 percent more likely to have a low sperm count than their peers and 81 percent more likely to produce no sperm.
There are many theories that explain this connection, some that were highlighted in the second article are:
– The greater fat storage can turn testosterone into the female hormone estrogen leading to slowing of sperm production.
– Overweight/obesity can alter the physical and molecular structure of germ cells in the testes and ultimately mature sperm.
– The Hormone Leptin which is produced by fat cells might be damaging sperm cells or those that produce them.
– Fat tissue causes temperature within the scrotum to rise; killing sperms.