Your wife may say she thinks your love handles are cute—you know, more to hold onto—but if you’re trying to have a baby, those extra pounds might matter.
Then again, they might not. Recent studies have come up with conflicting conclusions about whether extra weight on men makes a difference in the daddy department.
A recent study at the Utah Center for Medicine showed that obese men are three times as likely to produce unhealthy sperm. Coincidentally, a survey of over 5,000 men from the Aberdeen Fertility Centre in Scotland revealed that the roughly 2,000 guys in that sample with a body-mass index of over 30 (considered obese) produced 60 percent less seminal fluid with 40 percent more abnormal sperm. The most damning statistic comes from the U.S. National Institute of Environmental Health Sciences and implies that for every extra 20 pounds a man puts on, sperm production decreases by 10 percent. Fatty tissue produces an enzyme linked to estrogen production, which can interfere with the production of testosterone.
Guess those cheeseburgers have to go. . . but wait! An even newer study, this one at Albert Einstein College of Medicine in New York City, showed that weight doesn’t seem to have much effect on sperm. This survey included nearly 300 guys with an average BMI of 28 (overweight and close to obese) who’d donated sperm at fertility clinics. About one-seventh of the guys were tested for testosterone production, and in fact they did show lower than normal levels, but that turns out not to be a problem unless the levels are extremely low or the man is extremely obese. “Our results show that the process of making sperm is pretty robust and is hard to interrupt,” reports Nanette Santoro, M.D., a reproductive endocrinologist at Albert Einstein. “It’s good news for men that body size may be less related to fertility than it is in women.” (And I’ll take my cheeseburger rare, thank you.)