This pilot clinical trial studies protein-sparing modified fast (PSMF) intervention for weight loss in obese endometrial cancer survivors. The PSMF is a diet that is very low in carbohydrates and calories, designed to induce fast, safe weight loss. The diet consists of only lean meats (beef, pork, poultry, and seafood) in amounts adequate to meet protein requirements based on the individual's body weight. The PSMF may help endometrial cancer survivors achieve significant weight loss, reduce the risk of chronic disease, and improve quality of life.

PRIMARY OBJECTIVES:

I. Investigate whether the PSMF leads to significant weight loss in obese endometrial cancer survivors (ECS).

II. To assess whether the approach is feasible, whether participants will remain in the study for the duration of the intervention while adhering to the various components of the protocol. To assess feasibility, examine the following variables: drop-out rates; rates of adherence to diet and supplemental protocol; and rates of common side-effects.

III. Assess whether the PSMF improves biomarkers of disease risk in this population. To assess whether this objective has been met, assess the following variables: blood lipids (total cholesterol, low density lipid [LDL] cholesterol, high density lipid [HDL] cholesterol, and triglycerides); glucose; and markers of inflammation (C-reactive protein, interleukin-6, tumor necrosis factor [TNF]-alpha, and leptin).

IV. Assess whether the PSMF leads to improvement in quality of life related to weight loss.

OUTLINE:

PSMF: Participants are instructed by a registered dietitian (RD) to consume enough lean beef, pork, poultry, and seafood to provide 1.2 grams of protein per kilogram of their obesity adjusted ideal body weight. The protein recommendation will be communicated to participants in terms of grams per day. Participants are encouraged to adhere as closely as possible to the protein recommendation. Based on the protein recommendation, participants are advised to consume a given amount (in ounces) of beef, pork, poultry and seafood daily, assuming that each ounce of these products contains seven grams of protein. Participants are provided with a digital kitchen scale to weigh protein-containing foods and are permitted up to 2 servings of non-starchy vegetables per day. Participants remain on the PSMF until they have successfully reduced their initial body weight by 15% or up to 6 months. Participants are also provided with supplements to consume daily.

WEIGHT MAINTENANCE DIET: After successful weight loss of at least 15% of initial body weight, participants are instructed by a RD to consume a weight maintenance diet or they may remain on the PSMF. The weight maintenance diet consists of gradual addition of previously eliminated carbohydrate containing food groups to the PSMF and consumption of non-starchy vegetables is unlimited. Participants receive handouts that list common foods and the number of carbohydrates in each serving and educated on nutrition label reading for carbohydrates, with emphasis on serving size and total number of carbohydrates per serving.

After completion of study, participants are followed up at 2 and 4 weeks and then at 2, 3, 4, 5, and 6 months.

Inclusion Criteria:

• Previous diagnosis of endometrial cancer, successfully treated through surgery
• Body mass index (BMI) > 30 kg/m^2
• > 8 weeks removed from surgery to treat endometrial cancer

Exclusion Criteria:

• No previous diagnosis of endometrial cancer
• BMI < 30 kg/m^2
• Any history of cardiovascular, kidney, or liver disease
• Using medication to treat diabetes
• History of cardiac arrhythmias
• Inability to comply with follow up regimen
• Inability to read or speak English
• Abstention from meat and other animal products