Harvard: The Western Diet Devastates Sperm Count

A brand-new, 2019 study that was posted by Harvard’s School of Public Health, Environmental Health, and Nutrition Departments offers a troubling perspective on the health of today’s youth. Although it may seem like a pedestrian concept, diet affects one’s health, and researchers investigated to what extent diet affects sperm count in men [1].

It is already known that sperm count has been declining in Western countries.

According to a July 2017 report published by Oxford University Press, during a comprehensive meta-regression analysis lead by Dr. Hagai Levine, between 1973 and 2011, researchers noted a 50-60% decline amount men’s sperm counts in North America, Europe, Australia, and New Zealand [2].

The July 2017 reports did not include a small number of men either. The study was a meta-analysis that included 185 studies and 42,935 male participants who provided semen samples between 1973 and 2011. Moreover, those studies were well distributed over nearly 40 years of the study’s period and among the 50 different countries.

Further, American men reported an average decline in sperm concentration of 1.4% per year, with a 52.4% decrease during the 38-year study. Paradoxically though, men in South America, Asia, and Africa has no significant declines in their sperm concentrations and parameters.

While this 2017 study may give an unpopular truth, a study published in 1992, which was another meta-analysis that included 61 reviews worldwide, was one of the early warnings that sperm counts were dropping. However, that study’s results were highly controversial, and people were quick to pick out potential flaws in the research.

Regardless, with the plethora of studies that have been conducted within the last few decades, it is clear that there is indeed a decline.

Levine has also conducted previous studies. Before his 2017 publication, he had published studies which “show that exposure in utero to endocrine disrupting chemicals can harm male reproductive system development and fertility potential. Commonly used chemicals, including pesticides, lead and fire retardants, can increase or decrease production of certain hormones within our bodies and so are said to disrupt our endocrine, or hormone-making, system” [3].

Explanations for this trend have included obesity and climate change, naturally.

Michael Dourson, a professor in the Risk Science Center at the University of Cincinnati College of Medicine, gave his reason for the decline in sperm counts: “I suspect that obesity may have something to do with these trends, but measures of obesity, such as BMI (body-mass-index) were not analyzed” [3]. However, newer evidence has shown that diet and lifestyle is the main contributor to an individual’s BMI measurements [4].

Dourson also explained that sperm counts decrease in rising temperatures, so he believed global warming could play a regional role and explained that different states have different normal sperm measurements due to their temperature differences. However, someone would have to be hard-pressed to give a well-thought-out explanation of how climate change reduced men’s sperm counts nearly 60% in the last 38 years worldwide.

As first noted in this article, though, Harvard University researchers have given a different look at the issue.

In a study that included nearly 3,000 men, researchers investigated the effects that four, main world diets had on a man’s sperm count. The foods were as follows:

  • Western: characterized by intake of pizza, chips, processed, and red meats, snacks, refined grains, high-energy drinks, and sweets.
  • Prudent: characterized by intake of fish, chicken, vegetables, fruit, and water.
  • Smørrebrød: characterized by consumption of cold processed meats, whole grains, mayonnaise, cold fish, condiments, and dairy.
  • Vegetarian: characterized by intake of vegetables, soymilk, and eggs.


After the men’s diets were assessed by principal component analysis (PCA), the researchers measured testicular function by rating semen quality parameters (semen volume, sperm concentration, total count, etc.) and measuring serum levels of reproductive hormones, including estrogen and testosterone.

The researchers found that the Prudent diet was associated with the highest sperm count, followed by Vegetarian and Smørrebrød diets. The Western intake was associated with the lowest sperm parameter measurement and higher free testosterone concentrations, which could be attributed to hormones in the food and animal products influencing hormones in the men.

The Harvard University research team concluded, “Our findings support the growing evidence that adhering to generally healthy diet patterns, including local variations, is associated to higher sperm counts and more favorable markers of sperm function” [1].

The researchers believe that processed foods, which are very predominant in the Western diet, damage the health of sperm-producing cells called Sertoli cells. Even though the health of sperm can be recovered over time, the health of Sertoli cells cannot be corrected, meaning, despite if someone changed from the Western diet to the better Prudent diet, the damage is not wholly reversible.

It is impressive how shocked people seem to be at this finding, even though it should be common sense. This study has warranted organizations such as the New York Post, The Telegraph, Fox News, and The New York Times to post articles revealing how shocked they are.

Perhaps, these organizations should also examine the hundreds of studies that challenge the safety or productiveness of various vaccinations, but we are not supposed to know that [5] [6] [7].

In a previous article, I examined published, peer-reviewed studies which support that certain supplements and botanicals can help support or increase a man’s fertility. Some of those studied supplements include CoQ10, Vitamin C and E, and Zinc [8]. If you would read about the rest of the nutrients and the studies behind them, see reference [8].

While it is helpful to supplement the diet with a wide range of nutrients, one's diet should always come first. As noted in this study, diet matters and will influence a man’s fertility, regardless of their supplement intake.

If you have any questions about supplements which help support healthy male fertility, please feel free to call our office at 800.726.1834.



[1] https://www.eshre.eu/ESHRE2019/Programme/Searchable#!abstractdetails/0000574200

[2] https://academic.oup.com/humupd/article/23/6/646/4035689

[3] https://www.cnn.com/2017/07/25/health/sperm-counts-declining-study/index.html

[4] https://healthmasters.com/lifestyle-influences-body-mass-index-not-genes

[5] https://healthmasters.com/gardasil-vaccine-think-twice-about-its-safety

[6] https://healthmasters.com/measles-and-vaccines-review-unpopular-opinions


[8] https://healthmasters.com/how-increase-male-fertility