• Posted July 21, 2025

Male Virility Affected By Minimal Rises In Blood Sugar, Study Says

MONDAY, July 21, 2025 (HealthDay News) — Even small increases in blood sugar might put a dent in a man’s virility, a new study says.

Minimally elevated blood glucose levels are linked to a decline in sperm movement and erectile function, even if levels are below the threshold for diabetes, according to findings presented at the Endocrine Society’s recent meeting in California.

The results indicate that minor changes in a man’s health can affect their virility more than the ebbing of hormone levels that come with aging, researchers said.

“Although age and testosterone levels have long been considered an impetus for men’s declining sexual health, our research indicates that these changes more closely correlate with modest increases in blood sugar and other metabolic changes,” said lead researcher Dr. Michael Zitzmann, a professor at University Hospital in Muenster, Germany.

“This means that men can take steps to preserve or revive their reproductive health with lifestyle choices and appropriate medical interventions,” Zitzmann said in a news release. Eating a healthful diet, engaging in regular physical activity, and losing any extra weight can help keep blood sugar levels in check, according to the Mayo Clinic.

For the study, researchers recruited 200 healthy men ages 18 to 85 in 2014, and tracked them through 2020. By the end, 117 men were still participating.

Researchers studied changes in the men’s semen and hormone profiles, erectile function and markers of metabolic health like body mass index (BMI) and blood sugar levels. (BMI is an estimate of body fat based on height and weight.)

Over time, hormone levels and semen profiles remained largely within normal ranges, researchers said.

But sperm movement and erectile function declined in men whose blood sugar levels increased but remained below the diabetes threshold of 6.5% on the hemoglobin A1C blood test.

The results also showed that testosterone levels did not have a direct impact on erectile function, but did appear to affect men’s reported libido.

“We’re hopeful that the information gleaned from this study will help doctors and their patients formulate effective male sexual health maintenance plans,” Zitzmann added. “We now know that it’s in our power to retain sexual and reproductive well-being in men, even as they age.”

Researchers presented their findings July 12 at the Endocrine Society annual meeting in San Francisco.

Findings presented at medical meetings should be considered preliminary until they’re published in a peer-reviewed journal.

More information

The Cleveland Clinic has more on diabetes and sexual dysfunction.

SOURCE: Endocrine Society, news release, July 12, 2025