Dear Mark: Why are Male Fertility and Testosterone Levels so Low?

3d rendering group of white spermsFor today’s edition of Dear Mark, I’m answering just one question. But it’s a good (well, maybe not good, but certainly important) one: Why is male fertility on the rise and testosterone on the wane? The popular notion is that women flushing birth control pills and peeing estrogen-rich urine into the public water supply are the primary reasons for the sex hormone issues facing men, but I’m not so sure. Let’s explore what else might be causing the problem.

In the comments from last week, tribal wrote:

I also heard about a report that indicated that our water supply is also contains more and more estrogen, primarily due to the increased use of birth control tablets, which find their way into the water supply – I need to research the truth to this report. testosterone levels have halved for men in the last 20 years, and at this rate will will end up self-destructing.

The main thrust of your assertion is true.

The water supply is full of estrogenic compounds.

Male sex hormones have plummeted in the last half century and show little sign of rebounding.

However, birth control pill use isn’t the biggest culprit. In a 2011 review of the evidence, researchers found that the contribution of synthetic birth control estrogens to the total estrogen content of public water was negligible. Women flushing pills or excreting urinary estrogen do not appear to be the main cause of estrogen in the water supply.

Estrogen in the water may not even be the main cause of the growing male fertility problem. And if it were, what exactly could you do beside drink more bottled mineral water (and even that’s not a guarantee)? Spend thousands on expensive filters, stress out every time you had to satisfy a basic biological requirement (drink water)? It makes more sense to worry about the things you can control, like what you eat or how you live. As it turns out, the biggest culprits for impaired male fertility are probably dietary and lifestyle-related.

Omega-6/3 intake: The polyunsaturated fats we eat are incorporated into the structure of our cells—all the cells. Omega-6-rich cellular membranes are less stable than membranes with more MUFA, SFA, and omega-3 fats, and that goes for cellular membranes of sperm cells. Studies show that men with higher omega-6:omega-3 ratios have lower sperm counts, less sperm motility, and more infertility.

Oxidized fat intake: Most of the polyunsaturated fat most people eat has been refined, oxidized, and exposed to tons of heat, light, and oxygen. Omega-6 fatty acids are already liable to oxidize and turn rancid. They way we treat them before eating—as frying mediums for days on end, in high-heat stir fries, in packaged junk food subjected to high heat and left on the shelf for months—guarantees they’re almost completely damaged. The higher the MDA (a metabolite of oxidized PUFA) in the sperm, the greater the chance of male infertility.

Low sun intake: Most people fear the sun, focusing only on the skin cancer risk and ignoring the myriad benefits of sun exposure, one of which is the fact that it helps us synthesize vitamin D. Vitamin D is a pro-hormone, meaning we use it to produce a variety of hormones. One of the most important products of vitamin D is testosterone, the male sex hormone. Without adequate testosterone, reproduction becomes difficult. We produce less sperm, lose our libido, and become less attractive to potential mates.

Low red meat intake: The campaign against red meat has worked. Most people still think red meat is inherently dangerous. Red meat consumption is at an all-time low, and chicken consumption is at an all-time high. This development has probably caused major problems for male fertility. Red meat is the best and most reliable source of zinc, an important nutrient for male fertility. Red meat is the best source of carnitine, an amino acid with pro-fertility effects. Red meat is higher in fertility-protective saturated fat and monounsaturated fat and lower in unstable omega-6; chicken is lower in SFA and far higher in omega-6.

Those are the big whoppers, as I see it, the factors regular people suffering from low testosterone/fertility can actually target with the most ROI. Sure, it’s not going to happen overnight. Those seed oils are everywhere. Everyone loves French fries, and no one wants to know how long those fryers have been heating the same oil. Red meat remains scary, as does the sun. But it’s physically possible for a regular person to make four simple changes—eat less omega-6, have some canned sardines twice a week, choose steak over chicken, and go outside every day—that could have huge positive ramifications.

There are other major causes, too, including perhaps the estrogen in the water issue as well as other estrogen-like (xenoestrogen) pollutants. If you guys are interested, I can explore this topic more down the line.

Thanks for reading, everyone. I’d love to know your take on the issue. Let’s hear it!

Primal Kitchen Ketchup

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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