Overview

• A controlled crossover trial in 43 men found about 1 kilogram more fat mass accrued on an ultra-processed diet than on a minimally processed one despite matched calories and macronutrients.
• The same trial detected higher levels of the hormone-disrupting plasticizer metabolite cxMINP and reductions in testosterone and follicle-stimulating hormone during the ultra-processed phase.
• Participants followed three-week diet periods separated by a washout, and the excess fat gain on ultra-processed foods appeared regardless of whether men were on maintenance calories or an extra 500 calories per day.
• A German analysis of UK Biobank data in eClinicalMedicine tied higher all-cause mortality to greater intake of ultra-processed foods above roughly 18% of the diet and identified 12 specific additive markers, including certain sweeteners, flavour enhancers, sugars and processing aids.
• Researchers caution that the cohort relied on self-reported diet and that the trial was short and male-only, as a Nature editorial presses for clearer ultra-processed food definitions and precise policies, including on industrial trans fats.