A new study published in Cell Metabolism has revealed that ultra-processed foods may harm men’s reproductive health. Researchers found that such diets can lower testosterone levels, damage sperm quality, and increase body fat within weeks.
Ultra-processed foods—such as bread, biscuits, fast foods, sweets, ice cream, noodles, cereals, frozen meals, packaged yogurt, and soft drinks—are already known to raise risks of heart disease, stroke, and mental health issues.
The new research now suggests that these foods also contain plastic-like molecules that interfere with the hormonal system. Regular consumption increases cholesterol levels and contributes to weight gain, which can further harm overall health.
Inside the study
The study, conducted with 43 men aged 20 to 35, compared the effects of ultra-processed and unprocessed diets. Each participant followed an ultra-processed diet for three weeks and an unprocessed one for three weeks, with a three-month break in between.
Half of the men also consumed 500 extra calories per day, regardless of diet type. Researchers found that those eating ultra-processed meals showed higher levels of phthalate cxMINP—a chemical commonly found in plastic—which disrupts hormones.
Impact on hormones and fertility
Participants with higher levels of phthalate cxMINP had decreased testosterone and follicle-stimulating hormone, both crucial for sperm production. Alongside this, men on ultra-processed diets gained over one kilogram in weight and saw a rise in body fat.
Importantly, the decline in sperm quality was observed even when men consumed the same number of calories as those on unprocessed diets. This suggests that the type of food, not just the calories, plays a key role in reproductive health.
Experts noted that since the widespread introduction of ultra-processed foods in the 1970s, global sperm counts have dropped by nearly 60 percent. The study raises concerns that modern diets may be accelerating this decline through hormone-disrupting chemicals entering the body via food packaging.
