By Brett Spiegel
Manliness has often been associated with virility in the strictest sense of the word: the ability to procreate. And while you may not think of diet as a contributor to virility, there's growing evidence that a fatty diet can hamper sperm production.
Researchers at Rigshospitalet Copenhagen University National Hospital found a link between a diet high in saturated fats -- found in foods like cheeses and meats -- and shrinking sperm counts.
Between 2008 and 2010, the researchers collected self-reported diet information and semen samples from 701 Danish men, all roughly 20 years old, who were receiving military checkups. Among the Danes in the study who consumed the most saturated fat, there was a 38 percent decrease in sperm concentration, and, compared to those who ate less saturated fat, those who ate high-fat diets had sperm counts that were 41 percent lower.
Additionally, test subjects were broken down into four groups based on calorie intake from saturated fats and individual sperm production. The findings, published in The American Journal of Clinical Nutrition, showed that sperm concentration and sperm counts dropped as fat intake increased. Among men who got just over 11 percent of their calories from saturated fats, sperm concentration was 50 million per milliliter of semen with a sperm count of 163 million; that's compared to 45 million sperm per milliliter of semen and a sperm count of 128 million in those who had consumed 15 percent of calories from saturated fat.
The World Health Organization (WHO) says that a normal sperm concentration per milliliter of semen is anything above 15 million. Of the Danish men who ate the least saturated fat, 13 percent were below the WHO standard, and among those who ate the most saturated fat, 18 percent fell short.
"We cannot say that it has a causal effect, but I think other studies have shown that saturated fat intake has a connection to other problems and now also for sperm count," Tina Jensen, MD, PhD, lead study author from Rigshospitalet's Department of Growth and Reproduction, told Reuters Health.
A healthy diet has previously been associated with improved sperm production and quality. In 2011, Brazilian scientists discovered a link between eating more whole grains and increased sperm concentration and motility, and a link between eating more fruit and elevated sperm speed and agility.
Smoking and physical activity are also key players in optimal sperm production. Kick the nicotine to the curb and make sure to exercise regularly to maintain "the goods." And don't forget to cut back on saturated fats in general, as they have also been linked to heart disease, cancer, and other conditions.
"Eat More Saturated Fats, Lower Your Sperm Count" originally appeared on Everyday Health.
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The common household chemical bisphenol A (BPA) can lower sperm counts and motility, according to<a href="http://www.rodale.com/bpa-and-unexplained-infertility"> a study</a> in Reproductive Toxicology. Food packaging is a major source of BPA, which can seep into the food. Most food cans are <a href="http://www.msnbc.msn.com/id/41025571/ns/health-sexual_health/t/shooting-blanks-surprising-sperm-killers/#.ULaH2WmMF9R">coated with BPA resin</a>, and acidic canned foods are especially risky.
Certain plastics, including vinyl used in some sex toys, release phthalates — plastic-softening chemicals that have been <a href="http://news.harvard.edu/gazette/2003/05.22/18-semen.html">tied to lower reduced sperm count and quality</a>. Glass, silicone and green sex toys are a safer bet.
Phthalates are found in many shampoos, soaps, deodorants and shaving creams. Look for natural, phthlate-free products instead.
It's not surprising that smoking cigarettes is bad for sperm, but smoking weed isn't much better. Heavy marijuana smokers have been found to have <a href="http://news.bbc.co.uk/2/hi/health/3186686.stm">significantly lower sperm counts and sperm with bad swimming strategies</a>.
Stress can cut sperm count dramatically by <a href="http://scienceblog.com/community/older/1997/B/199701021.html">inhibiting the production of testosterone</a>.
Women aren't the only ones who should slow down on drinking while trying to conceive. Alcohol can <a href="http://menshealth.about.com/cs/stds/a/healthy_sperm.htm">inhibit sperm production</a> and lower sperm counts.
BPA is found on about 40 percent of cash register receipts, according to <a href="http://www.sccma-mcms.org/full+article/bisphenol+a+in+cash+register+receipts/">a 2010 University of Missouri study</a>. The chemical can penetrate skin or be passed from hand to mouth to the digestive track. Skip the receipt or wash your hands after signing.
Isoflavones found in soy products <a href="http://www.isoflavones.info/">mimic estrogen</a>, and a <a href="http://www.washingtonpost.com/wp-dyn/content/article/2008/07/25/AR2008072502985.html">2008 study</a> linked soy consumption to significantly lower sperm counts. The soy food industry <a href="http://www.foxnews.com/story/0,2933,303160,00.html">disputed the study's findings</a>.
Polychlorinated biphenyls (PCBs) are a group of toxic chemicals that have been banned but have accumulated in certain fish — especially predator fish and bottom-feeders. They are associated with <a href="http://www.epa.gov/teach/chem_summ/PCB_summary100809.pdf">decreased sperm counts and integrity</a>. Smaller, younger fish <a href="http://www.dhs.wisconsin.gov/eh/hlthhaz/fs/pcblink.htm#Which fish are safer to eat?">are considered safer</a>.
Chemicals called perfluoroalkyl acids are used in the manufacturing of nonstick products such as Teflon, Gore-Tex and wax paper and can significantly lower sperm counts, according to <a href="http://www.rodale.com/male-infertility-and-nonstick-chemicals">a Danish study</a>.
Of course not having sex at all won't help, but some couples abstain for days or weeks in hopes of saving sperm until the woman is ovulating. This doesn't work. Researchers have found that while it does take a day or two for sperm to replenish themselves after ejaculation, waiting any longer than that <a href="http://www.guardian.co.uk/uk/2003/jun/30/highereducation.sciencenews">can cause them to lose motility and change shape</a>.