Men and Women Lose Weight Similarly Under Energy Restriction Sub-analyses of the DIETFITS trial reveal that, although small sex-based differences emerge under specific diets, the overall rules of energy balance apply equally to healthy adults. • Diet composition and absolute weight loss – In a 12-month comparison of a healthy low-carb (HLC) vs. healthy low-fat (HLF) diet, men on HLC lost ≈3 kg more weight (and more lean mass) than on HLF, whereas women lost similar weight and body fat (because women are much more metabolically flexible and rely on fat more than men and spare protein) on both diets – Adherence patterns contributed: men adhered better to HLC, women to HLF—but after adjusting for adherence, diet-type differences in women vanished. PMID: 33188301 PMCID: PMC7752762 DOI: 10.1038/s41366-020-00708-y • Resting energy expenditure (REE) reflects body composition, not sex – When REE is indexed allometrically to lean body mass (LBM) and fat mass (FM), sex differences disappear ...