New studies out show that obese men may be at greater risk for infertility than men of normal weight.
How big is a problem is? Let’s start with that. Well, this seems like it is going to be a very big problem for us and it’s getting worse. We know that there is certainly an epidemic of obesity, that’s a global problem and about a third of adult now are considered obese. Parallel to that, there’s been an increase in male infertility. And the rate of male infertility seems to be going up and up along with the increase in obesity.
How far back did the red flag go up, when you could link obesity with infertility? It’s gone back quite a ways, you know, we certainly clinically see more men that are overweight, that do have more difficulty achieving pregnancy, and we have known scientifically why some of those reasons are for some time, but we are learning more and more about it now.
The most recent study that’s came out as a meta-analysis that actually looks at data from 14 different studies, that covers almost 10,000 men. And we see a man that are normal weight have more normal semen parameters and more normal sperm counts compared to the ones that are overweight. In fact, the ones that are overweight, the percentage of men that have normal semen parameters really goes down quite a bit, it goes from about a quarter of men that have low sperm counts in the normal weighted men, up to about a third of men, when they’re considered obese. The number of men that had no sperm in their semen whatsoever, the percentage of men goes up from about 2.6 percent to almost 7 percent. So that is a massive increase. That seems to be strongly associated with their weight.
We certainly do encourage men to try to get more fit, to burn their body mass. We believe there are a few different mechanisms, that are affecting their fertility, when they are obese. We know, that there are protein and fat cells that turn a man’s testosterone into estrogen. And it’s normal for men to have a certain level of estrogen, but as you put on more fat cells, you produce more estrogen, and that testosterone to estrogen ratio decreases. And we know that this afters fertility. Pills may help
Also when you put on more fat cells in the lower pelvis, in the scrotal area, that may increase temperature around the testicles and that’s also bad for sperm production. Testicles are located basically outside of the body because sperm is produced best at about 2-4 degree cooler temperature, than the core body temperature. So that temperature change can affect sperm production as well.
Fertility is a very big motivator. Couples that want to build a family are very motivated to do what it takes, and they certainly are proactive in getting a healthier diet, low-fat, low-cholesterol diet, and adding cardiovascular exercising. And that’s a great first step.