Sperm quality linked to living longer, new study finds

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People who have higher levels of strong, agile sperm may live nearly three years longer than those with poor swimmers incapable of making it to their destination, according to new research. The large-scale study followed more than 78,000 men for 50 years.

The ability of sperm to properly swim through the female reproductive tract to reach and fertilize an egg is called motility.

“In absolute terms, men with a total motile count of more than 120 million (per milliliter of semen) lived 2.7 years longer than men with a total motile count of between 0 and 5 million,” said lead study author Lærke Priskorn, a researcher and doctoral candidate at Copenhagen University Hospital — Rigshospitalet in Denmark, in a statement.

To translate that into ages, a man with extremely poor sperm motility might be expected to live up to 77.6 years, while a man with extremely high motility might survive to 80.3 years, according to the study published Tuesday in the journal Human Reproduction.

“The fact that there is an association between semen quality and longevity is an important finding,” said Dr. Michael Eisenberg, professor of urology and director of male reproductive medicine and surgery at Stanford University School of Medicine. He was not involved in the new research.

“There have been prior studies that suggest this link between reproductive health and overall health,” Eisenberg said in an email.

Could sperm count be a ‘canary in the mine’?

In the new report, researchers compared the quality of sperm samples taken between 1965 and 2015 from men undergoing infertility testing in Copenhagen. The quality of the men’s sperm was then compared with national medical records gathered by the Danish national health service.

“The lower the semen quality, the lower the life expectancy,” Priskorn said. “This association was not explained by any diseases in the ten years before semen quality assessment or the men’s educational level.”

Motility counts are typically provided in percentages, not total numbers. The World Health Organization considers a man’s sperm normal if about 42% of the sperm in each sample of ejaculate is capable of swimming to their destination.

However, a motility count of less than 5 million per milliliter of semen is associated with a severe case of oligospermia, or low sperm count, which often leads to male infertility, the study said.

A sperm motility of about 125 million per milliliter of semen is normal for a fertile male, Eisenberg said. However, that doesn’t guarantee male fertility, experts say.

If not for fertility, why would testing semen be a benefit? Because it could also be a marker for male health problems at younger ages, said John Aitken, a distinguished professor emeritus from the School of Environmental and Life Sciences at the University of Newcastle, Australia, who was not connected to the study.

“In men, it appears to be their semen profile that is providing the most significant information concerning their future health and wellbeing,” Aitken wrote in an editorial published alongside the study.

“If spermatozoa really are the canaries in the coal mine of male health, the obvious question to ask is, why?” Aitken posited. “What possible factors could link the ultimate life expectancy of males with the quality of their semen profile in early adulthood?”

Oxidative stress is one possibility

According to Aitken, one answer explaining the association might be oxidative stress, caused when free radicals run rampant. Free radicals are unstable molecules that can damage DNA and cellular function and lead to cell death throughout the body, including the testes and sperm.

“Any factor (genetic, immunological, metabolic, environmental or lifestyle) that enhances overall levels of oxidative stress, could reasonably be expected to drive changes in the semen profile and subsequent patterns of mortality,” Aitken posited.

Smoking, excessive alcohol, sun exposure, pesticides, industrial chemicals and air pollutants are just a few of the ways free radicals are activated, according to the National Cancer Institute.

The body does have a way to fight back — with antioxidants. Nicknamed “free radical scavengers,” antioxidants can prevent and repair damage caused by some types of free radicals, experts say.

While supplements have failed to show promise against free radicals, fruits, vegetables, nuts and grains with key vitamins and minerals are excellent sources of antioxidants, according to the Cleveland Clinic.

Citrus fruits, red and green peppers, and broccoli are full of the antioxidant vitamin C, while nuts, sunflower seeds, spinach and broccoli are good sources of vitamin E, another antioxidant, the clinic states on its website.

Salmon and tuna contain selenium, as does brown rice, eggs and whole wheat bread. Beta carotene, another antioxidant, can be found in carrots, apricots, kale, mangos and sweet potatoes.

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