Researchers are revisiting long-standing assumptions about how ejaculation frequency may affect sperm health. For years, popular advice around male fertility has included everything from dietary changes to limiting sexual activity, yet many of these beliefs were based more on speculation than science.

Trends like “No Nut November” have also promoted the idea that abstaining from ejaculation boosts testosterone or improves fertility. Medical experts, however, generally disagree. Some research suggests that long periods without ejaculation may contribute to increased stress or low mood rather than offering physical benefits.

Emerging scientific findings point in another direction. A major review from the University of Oxford examined 115 studies involving nearly 55,000 men and found that extended abstinence was linked to declines in important markers of sperm quality. These included reduced movement, lower survival rates, and greater DNA damage

The research suggests that when sperm remain stored for too long, they may naturally begin to deteriorate. Allowing too much time between ejaculations may therefore work against those trying to support fertility.

In contrast, more frequent ejaculation—through sexual activity or masturbation—may help maintain healthier sperm. By clearing out older cells, the body has the opportunity to produce newer, more functional ones. Some scientists describe this as keeping the reproductive system “refreshed.”

Other studies have explored broader health effects. A long-term Harvard study found that men who ejaculated 21 or more times per month had a significantly lower risk of developing prostate cancer compared to those who ejaculated less often, even after accounting for lifestyle differences.

Researchers are still studying the underlying biology. Some theories involve oxidative stress, which can build up over time and damage cells, while others suggest that older sperm lose energy the longer they remain unused.

Overall, current evidence leans toward regularity rather than long stretches of abstinence for those concerned about fertility. While individual needs vary, the research supports the idea that balanced, moderate habits may best support reproductive health.