At least 21 times a month, to be exact.

Dr Lorelei Mucci, a professor of epidemiology at the Harvard T.H. Chan School of Public Health and a co-author of emerging research on prostate cancer and ejaculation, told The Post that her team has come across some interesting patterns.

Data from a long-term health and lifestyle study assessing more than 50,000 men since 1986 suggests that those who ejaculate 21 or more times per month had a 19-22% lower risk of prostate cancer than those who came less, she said.

“The ’21 or more’ isn’t a strict biological magic number, but rather a finding that emerged from our robust statistical analysis,” Mucci revealed, adding that her team has even observed small reductions in risk for men who ejaculated only eight times per month.

“While 21 is the benchmark we identified,” she continued, “the broader implication is that more frequent ejaculation may offer a greater potential benefit.”

According to the American Cancer Society, prostate cancer is the second most common cancer in US men, after skin cancer, as roughly 1 in 8 men will be diagnosed in their lifetime.

It’s also the second-leading cause of cancer-related death in men, behind lung cancer.

Here in Australia, it’s the most commonly diagnosed cancer in men.

According to Cancer Australia, 1 in 5 men are at risk of being diagnosed by the time they reach 85.

And while the “precise biological mechanisms” at play are still being studied, prevailing theories suggest that “frequent ejaculation may help ‘flush out’ potential carcinogens, reduce inflammation within the prostate or even influence gene expression in the normal prostate tissue,” Mucci said.

“It’s a fascinating area to explore, and these observational findings have been reinforced by other large studies.”

Yael Cohen, co-founder of FCancer, told The Post that the nonprofit’s campaign was ultimately designed with education in mind.

Ultimately, she added, “what matters is men knowing that something they likely already do could actually benefit their health” – something most men aren’t aware has anti-cancer benefits.

Cohen knows that cancer prevention isn’t typically so lighthearted, but this new research presented a unique opportunity.

“This might be the only prevention tip that’s genuinely fun,” she said.

“Usually, prevention is all about what you ‘should’ or ‘shouldn’t do. This is one ‘should’ most people won’t mind adding.”

Though the campaign spotlights masturbation, Mucci said the research “focused on ejaculation frequency, regardless of the specific activity that leads to it.”

Mucci believes a campaign like this could encourage more and earlier prostate cancer screenings, putting patients in a better position to advocate for their health.

“I strongly support this campaign because it takes robust scientific findings and turns them into a conversation men can actually have, breaking down barriers and encouraging them to engage with their prostate health, understand their personal risk and seek appropriate screening and advice from their physician,” she said.

At the end of the day, coming is only half the battle, the other half is going … to the doctor.

“It’s about making sure you’re getting the appropriate screening, understanding your risk factors and actually talking to your physician,” Cohen said.

“No one else will do that for you, so take control, both in the fun way and the critical way. At the end of the day, it’s about putting your health in your own hands and then passing the ball to your doctor for the next play.”

This story originally appeared on the New York Post and was reproduced with permission.