Effect of High Protein Weight Loss for Seniors

Intentional weight loss in obese, older adults remains controversial. Although caloric restriction, resulting in significant weight and fat mass loss, ameliorates many clinical consequences of obesity, recommendation of intentional weight loss in aging remains controversial. Reluctance stems, at least in part, from loss of lean and bone mass known to accompany overall weight loss and potential exacerbation of age-related risk of disability and fracture. Accordingly, current treatment guidelines call fhttp://google.wfu.edu/or weight-loss therapy that minimizes muscle and bone losses for older persons who are obese and who have functional impairments or medical complications that can benefit from weight loss. Amount of dietary protein consumed during caloric restriction may be a key determinant in maintaining fat-free mass during weight loss. Adequate dietary protein is essential for skeletal muscle anabolism; and, epidemiological evidence in older adults point to a salutary effect of protein intake above the current RDA (0.8 g/kg/day) on body composition. Indeed, a recent position statement by the PRO-TAGE study group advises consumption of 1.0-1.2 g/kg/d in older adults during weight-stable conditions to aid in the maintenance of lean body mass and function. Practical achievement of this level of protein intake is often difficult for obese, older adults undergoing weight loss, yet may be critical to offset weight loss-associated lean mass loss. Preliminary data from our group show a lean mass sparing effect of high protein consumption during caloric restriction. In post-menopausal women undergoing a 5-month intentional weight loss program, consumption of a high (1.2 g/kg/day) versus low (0.6 g/kg/day) protein diet was associated with 50% attenuation (17% vs. 37%) of lean mass loss. While promising, results have yet to be translated to functional changes in a tightly controlled trial of weight loss in obese, older adults. The primary goal of this study is to determine whether adherence to a high protein (≥1.0 g/kg/d) weight loss program results in improved physical function by favorably affecting body composition compared to weight stability in obese, older adults. This will be accomplished by conducting a 24-week trial in 124 obese (BMI 30-40 kg/m2), older (65-79 years) men and women, at risk for mobility disability, randomized to either: (1) high protein intake (≥1.0 g/kg/d; n=62) during weight loss, or (2) weight-stable control (n=62).