The effects of a higher protein intake during energy restriction on changes in body composition and physical function in older women 

Protein is considered a good way to increase satiety and feelings of fullness. The purpose of this double-blind randomized clinical trial was to compare the relative effectiveness of a higher protein and conventional carbohydrate intake during weight loss on body composition and physical function in older women. 31 overweight/obese, post-menopausal women were randomized to either a 25 g whey protein supplementation group or a placebo group, while also being prescribed a reduced calorie diet (1400 Kcal/day) for six months. Assessments of efficacy included: Lean soft tissue (LST) via dual-energy X-ray absorptiometry; thigh muscle, subcutaneous adipose tissue (SAT), and intermuscular adipose tissue with magnetic resonance imaging; knee strength with isokinetic dynamometry; balance and physical function with a battery of performance tests. The results showed that the whey protein supplementation group lost more weight than the placebo. 

References:

Mojtahedi, M. C., Thorpe, M. P., Karampinos, D. C., Johnson, C. L., Layman, D. K., Georgiadis, J. G., & Evans, E. M. (2011). The effects of a higher protein intake during energy restriction on changes in body composition and physical function in older women. The journals of gerontology. Series A, Biological sciences and medical sciences, 66(11), 1218–1225. https://doi.org/10.1093/gerona/glr120