Uh-oh: Study Finds Vegetarians and Vegans Have Lower Sperm Counts


There’s new research out on male fertility around two topics that I care deeply about: the declining fertility of humans, and the troubling increase in birth defects.   For men, sperm quality and motility are great leading indicators of how healthy you are. Men with lower quality sperm have a higher incidence of children with birth defects.

The Bulletproof Diet has various known benefits from increased energy to weight loss to better skin, but increased fertility has also been on the list ever since my wife Dr. Lana and I created The Better Baby Book after restoring our own fertility as a couple.  In addition to placing an emphasis on healthy fats in your diet, the Bulletproof Diet also includes significant quantities grass-fed meat, wild caught fish, and other upgraded proteins that always come stuck to those fats!

A new four-year study out of Loma Linda University Medical School released findings this month that a meat-eating diet can even make a difference when it comes to male fertility – specifically sperm density and motility.

The study found that vegetarians and vegans had an average of 51 million sperm per milliliter, compared to 70 million sperm per milliliter amongst the meat-eaters studied – an almost 30% fewer sperm count. [i]

This research takes advantage of the fact that a large vegetarian population, the Seventh-Day Adventist Christians, is found living in Southern California in close proximity to Americans eating a meat-inclusive diet.  It provides a natural control group of meat-eaters versus vegetarians living in the same region.

The American Society for Reproductive Medicine press release states:

“Researchers…found that vegetarians have significantly poorer sperm concentration and motility than non-vegetarians.  In a retrospective study, results from semen analyses conducted between 2009 and 2013 on 26 vegetarians, 5 vegans, and 443 non-vegetarians were compared.  Vegetarians had significantly lower average sperm concentrations (51 million/milliliter vs. 70 million/milliliter) than the non-vegetarians and lower average sperm motility (33% vs. 58%), however their results were not classified in the infertile range.”[ii]

The full study findings, conducted by lead study author Eliza Orzylowska and team, will not be released until December.[iii]  While the study is not conclusive – it only compared 26 vegetarians and 5 vegans alongside 443 meat eaters – this certainly isn’t the only research on this topic.  Another recent study also found that pesticides may be hurting sperm in men who eat a high non-organic fruit and vegetable diet[iv] – yet another reason to eat organic and in the green zone of the Bulletproof Diet!

There is ample additional evidence that a diet including healthy, high quality non-industrial meat is effective for increasing fertility for both men and women.  Several other studies Dr. Lana and I laid out in the Better Baby Book also have shown that vegetarians and vegans have weaker sperm and fertility.

The conclusion was: “While more research is needed, the researchers postulate that estrogenic compounds and/or chemical residues in the vegetarians’ diets could be a cause for poorer sperm parameters.”

I don’t believe this because meat eaters can get *more* estrogenic pesticides that bioaccumulate in industrial CAFO meat compared to vegetarians, and this study wasn’t comparing grass-fed natural omnivores to organic vegetarians. We also don’t know if those vegetarians and vegans were “Pepsi and Frito-Lay” vegetarians or healthy ones.

In any case, perhaps this study will give you pause if you are considering starting a family on a vegan or vegetarian diet…at least consider adding in dairy fat, and hopefully moderate high quality animal protein from ethically raised animals. The environment will thank you, and given the power of epigenetics, so will your kids and grandkids.

Check out these other recent Bulletproof resources on food, fertility, and sex:



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[i] http://www.fertstert.org/article/S0015-0282(14)01556-8/fulltext


[iii] Forthcoming: Orzylowska et al, “Decreased Sperm Concentration and Motility in a Subpopulation of Vegetarian Males at a Designated Blue Zone Geographic Region,” P-408 EM

[iv]YH Chiu et al, “Fruit and Vegetable Intake and Their Pesticide Residues in Relation to Semen Quality and Fertilization Rates Among Subfertile Men”





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