Study: About a quarter of Army men test low for testosterone
About a quarter of Army men tested below a common cutoff for low testosterone in a new JAMA study, Defense News and Ars Technica reported. The researchers said the Pentagon's new tests for men 30 and older could lead to many repeat tests and doctor visits. Medical groups have said not to screen all men, Ars said.
About a quarter of male active-duty Army soldiers had testosterone levels below a widely used low threshold, according to a study published Thursday in JAMA, Defense News and Ars Technica reported.
Researchers from the Pennington Biomedical Research Center in Louisiana and the U.S. Army Research Institute of Environmental Medicine in Massachusetts measured morning testosterone in 479 male soldiers at five Army installations, Ars reported. The samples were collected from August 2024 through January 2026, the outlets said.
About 20% of soldiers under 30 and 32.8% of those 30 and older fell below 300 nanograms per deciliter, the American Urological Association's threshold, Defense News reported. Extrapolated to the whole Army, about 26% would get a result suggesting low testosterone, Ars reported.
The researchers said the results show what the Defense Department may face under a new program, announced by Defense Secretary Pete Hegseth in July, that requires men 30 and older to be screened, Defense News reported. The results "suggest that routine testosterone screening will result in confirmatory testing and clinical evaluation for many male service members," the researchers wrote, according to Defense News.
The authors noted that the low levels do not mean all of those soldiers have hypogonadism, the medical condition, Defense News reported. "Because testosterone replacement therapy is long term and has potential adverse effects, distinguishing an isolated low screening value from clinically significant hypogonadism is essential," they wrote.
Testosterone levels can dip because of age, time of day, obesity, illness, physical stress, poor sleep and some medications, Ars reported. Groups including the Endocrine Society and the AUA have recommended against blanket screening, and clinically significant low testosterone affects at most 1% of men, Ars said.
Under the Pentagon's guidance, service members will be tested on two separate mornings, and treatment will not be mandatory, Defense News reported. Treatment can carry side effects, including blood clots and low sperm counts that can cause infertility, the outlet said.
What we know: In the JAMA study, about 1 in 4 Army men tested below 300 ng/dL, and researchers expect many follow-up visits.
What we don't: How many soldiers will actually be tested and treated under the new program.
Where outlets agree Defense News and Ars Technica both report that the JAMA study found roughly a quarter of Army men below the 300 ng/dL threshold and that screening could trigger many follow-up evaluations.
Where they differ The outlets cited here report the same key facts so far.