Overview
- The Generation R findings, published Tuesday, link higher paternal ultra-processed food intake to lower chances of conceiving each month and greater subfertility risk.
- The same Dutch cohort reports that higher maternal intake is tied to slightly smaller embryos and yolk sacs at about seven weeks of pregnancy, with differences waning by weeks nine and eleven.
- A separate U.S. study using 2013–2018 NHANES data finds that women who eat more ultra-processed foods have lower odds of being classified as fertile, and any Mediterranean-diet edge weakens after adjusting for obesity.
- Researchers caution that the evidence is observational and based on diet questionnaires and self-reported fertility, and they outline plausible pathways such as nutrient gaps, inflammation, microbiome shifts and chemical exposures without claiming causation.
- Ultra-processed foods accounted for about 22% of women’s intake and 25% of men’s in the Dutch sample and roughly 27% in U.S. women, showing broad exposure that could matter even with small effects.