Why junk food might hurt your body and sperm
Effect of ultra-processed food consumption on male reproductive and metabolic health.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
People ate either regular food or super-processed food for a while, then switched. The processed food made them gain weight, raised bad cholesterol, lowered some important hormones, made sperm move slower, and left more chemicals in their blood—even when they ate the same number of calories.
Surprising Findings
Ultra-processed food harmed metabolic and reproductive biomarkers even when calories were held constant.
Common belief is that processed foods are bad because they cause overeating. This study shows they’re harmful even without extra calories.
Practical Takeaways
Swap one ultra-processed meal per day for a whole-food alternative (e.g., swap packaged granola bar for nuts and fruit).
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
People ate either regular food or super-processed food for a while, then switched. The processed food made them gain weight, raised bad cholesterol, lowered some important hormones, made sperm move slower, and left more chemicals in their blood—even when they ate the same number of calories.
Surprising Findings
Ultra-processed food harmed metabolic and reproductive biomarkers even when calories were held constant.
Common belief is that processed foods are bad because they cause overeating. This study shows they’re harmful even without extra calories.
Practical Takeaways
Swap one ultra-processed meal per day for a whole-food alternative (e.g., swap packaged granola bar for nuts and fruit).
Publication
Journal
Cell metabolism
Year
2025
Authors
Jessica M Preston, J. Iversen, Antonia Hufnagel, Line Hjort, Jodie Taylor, Clara Sanchez, Victoria George, Ann N Hansen, Lars Ängquist, S. Hermann, Jeffrey M. Craig, S. Torekov, Christian Lindh, K. Hougaard, Marcelo A. Nobrega, Stephen J Simpson, R. Barrès
Related Content
Claims (5)
Eating a lot of processed foods may lower two important hormones—one that helps control appetite and another that helps make sperm—which could hurt both your metabolism and fertility.
People who eat a lot of processed foods may have more toxic chemicals from packaging in their blood and less of a naturally occurring mineral called lithium, which might help explain why these foods are harmful.
Eating lots of highly processed foods like chips, sodas, and frozen meals can make you gain weight and worsen your 'bad' cholesterol compared to 'good' cholesterol—even if you eat the same number of calories as someone eating whole foods.
Men who eat mostly processed foods may have sperm that don’t swim as well, which could make it harder to get a partner pregnant—even if they’re otherwise healthy.
Just eating more or fewer calories affects your body differently than eating processed foods—even if the total calories are the same.