Ads from a booming testosterone industry remind us of this constantly, as do food and fitness “hacks” touted by so many influencers.

The , published in The Journal of Urology, argues that the standard cutoff point for clinically low testosterone levels in men needs to be adjusted.

But the study researchers argue that what counts as low T depends on a man’s age — an aspect previously overlooked because most data collected came from men over 40.

“The concept of age-appropriate thresholds for testosterone deficiency makes a lot of sense,” says Guillaume Paré, M.D, a molecular epidemiologist at McMaster University in Ontario, Canada, who was not involved in the study.

“Our own research suggests it could lead to an increased risk of prostate cancer, high blood pressure, and baldness,” he says, pointing to his 2020 study in the journal eLife.

To avoid unnecessary treatment, it’s important not to interpret testosterone levels in isolation, says Richard Anderson, Ph.D., M.D., co-director of the Centre for Reproductive Health at The University of Edinburgh in Scotland, who wasn’t involved in the study.