Even mild elevations in blood sugar levels can reduce fertility in men.

Research shows that in men with only slightly elevated blood sugar levels - even below the threshold for diagnosing diabetes - sperm motility and erectile ability are significantly impaired.

A new study suggests that age isn't the only culprit behind declining male sexual function – a slight increase in blood sugar plays a much larger role.

The six-year study, presented at the American Endocrine Society's annual ENDO 2025 conference, tracked 200 healthy men (aged 18 to 85, without diabetes, heart disease, or cancer) to investigate the link between metabolism and reproductive function.

The results showed that although hormone levels and semen parameters generally remained normal over time, sperm motility and erectile function were significantly reduced in those with only slightly elevated blood glucose levels—even below the diagnostic threshold for diabetes (HbA1c below 6.5%).

Professor and physician Michael Zitzmann of the University of Muenster Medical School (Germany) stated: "It has long been believed that age and testosterone levels are the main causes of declining male sexual health. But our research shows that this link is more closely tied to metabolic changes when blood glucose levels rise slightly."

Specifically, testosterone doesn't directly affect erectile function, but it is related to libido. Meanwhile, even a slight increase in blood sugar levels negatively impacts sperm quality and erectile function.

The study, part of the FAME 2.0 project, began in 2014 with 200 participants and ended in 2020 with 117 people still following the project.

The authors collected data on metabolic indices (BMI and HbA1c), assessed erectile function and libido, and conducted periodic semen analyses.

According to Dr. Zitzmann, the positive aspect is that men can actively maintain their long-term reproductive and sexual health through lifestyle changes and timely medical treatment.

He stated: "We hope these results will help doctors and patients develop effective plans for protecting and restoring sexual health. Maintaining sexual and reproductive health is entirely within reach, even as we age."

(VNA/Vietnam+)

Source: https://www.vietnamplus.vn/chi-so-duong-huyet-tang-nhe-cung-lam-giam-kha-nang-sinh-san-o-nam-gioi-post1049471.vnp