A High Protein Weight Loss Intervention for Sarcopenic Obesity in Women

Assess the effects of combining regular, generous intakes of high quality protein (primarily from lean pork and other animal source proteins) with calorie restriction on functional status and lean muscle mass in frail, obese, women who participate in a 6 month intervention and 9 month intervention. For 6 month intervention: Participants will be randomized into one of two study arms: Weight Loss Control (n = 20) subjects follow a calorie-reduced diet for a weight loss or ≥10%; or Weight Loss-High Protein: (n = 40) subjects follow a calorie-reduction diet for a weight loss of ≥10%, with a high proportion of high quality protein at each meal. Intakes of \> 30g of high quality protein will be achieved three times a day by subjects in this group, predominantly all from animal sources and 60-70% of animal protein from pork. Subject criteria will include obese (\>30 kg/m2) women (≥ 45 yrs.) with mild to moderate functional impairment (by 6 minute walk). For 9 month intervention: Participants will be randomized into one of two study arms: Weight Loss Control (n = 10) subjects follow a calorie-reduced diet for a weight loss or ≥10%; or Weight Loss-High Protein: (n = 10) subjects follow a calorie-reduction diet for a weight loss of ≥10%, with a high proportion of high quality protein at each meal. Intakes of \> 30g of high quality protein will be achieved three times a day by subjects in this group, predominantly all from animal sources and 60-70% of animal protein from pork. Subject criteria will include obese (≥ 30 kg/m2) women (≥ 60 yrs.) with mild to moderate functional impairment (by 6 minute walk). This is a randomized clinical trial with repeated measurements, with the purpose of assessing change over time for the overall sample and the difference in the High Protein group relative to the Control group with regards to primary outcomes (function and lean body mass). The statistical analyses will proceed chronologically in 3 phases: 1) descriptive analyses that will summarize the distribution of the covariates and dependent variables, 2) bivariate analyses of the association between group membership and the outcome measures, and 3) controlled multivariable analyses, which assess the association between experimental group and the outcomes, controlling for the important covariates.