Human study · Research · 2 Aug 2026
Higher body-fat percentage tracked lower sperm counts in young Danish men with normal BMI
Source: News-Medical
What the research found
Study (observational). In the FEPOS cohort of 1,058 Danish men around age 19, higher body-fat percentage by bioelectrical impedance was associated with lower total sperm count even when BMI was in the normal range: about 23% lower count in the high body-fat group versus normal body-fat. Hormones shifted (lower testosterone and SHBG, higher LH and estradiol). Motility, morphology, and testicular volume were not clearly different. Association in young men, not a fertility diagnosis and not a reason to start hormone therapy. Educational metabolic/reproductive notes.
Evidence level: Human study. A study in people, but an association isn't proof of cause.
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