Protein Leverage · 9 cited studies

Research on Protein Leverage

The protein-leverage hypothesis, advanced by Simpson & Raubenheimer (Obesity Reviews 2005), proposes that humans defend an absolute daily protein target — and when dietary protein concentration drops, total energy intake rises to compensate. Gosby 2011 (PLOS ONE) tested this in a controlled diet RCT: dropping protein from 15% to 10% of calories produced a 12% rise in total energy intake. Bray's 2012 JAMA inpatient overfeeding study showed low-protein groups gained more fat and less lean mass at matched calories. Weigle 2005 found increasing protein from 15% to 30% triggered a spontaneous 441 kcal/day reduction in ad-libitum intake. Westerterp 2004 quantifies the thermic-effect-of-feeding cost: 20–30% for protein vs 5–10% for carb and 0–3% for fat. Phillips's 2016 'beyond the RDA' paper situates the optimum at 1.2–1.6 g/kg for body composition, satiety, and aging. Below: the protein-leverage and protein-quantity literature.