Men trying to conceive may want to hold off on the bacon.
According to a new study from Harvard University, the intake of processed meat is associated with lower semen quality in men. Researchers from the Harvard School of Public Health presented on the link between bacon and male fertility at the 2013 American Society for Reproductive Medicine conference Monday.
Drawing their male subjects from Massachusetts General Hospital Fertility Center, the team analyzed sperm samples of 156 volunteers and compared them to each participant's food intake, as reported on a food intake questionnaire. After adjusting their statistical models for other factors, such as age and body mass index, the team found a negative association between processed meat -- including hamburgers, hot dogs and bacon -- and sperm quality.
"Processed meat was associated with lower sperm concentration and morphology," lead researcher Dr. Myriam Afeiche, of the university's Department of Nutrition, wrote in an email to The Huffington Post. (Morphology refers to the structure and appearance of the sperm.)
While the team found that eating more than one serving of bacon, or other processed meats, related to diminished semen quality, the study also noted a positive association between male fertility and fish consumption.
According to the research, white meat fish like cod and halibut were associated with a higher percentage of normal sperm. Salmon, tuna and other dark meat fish, on the other hand, were related to a higher total sperm count.
Though it seems the findings may add to the growing list of factors that can negatively affect the potency of little swimmers -- like too much TV -- Afeiche is hesitant to make any diet recommendations for men hoping to conceive, since data is limited.
"The existing literature on diet in general and semen quality is scarce," Afeiche told HuffPost. "We'll continue looking into this question including the possibility that it is not processed meats that is driving the association but what they are replacing."
Related on HuffPost:
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>.