Optimizing Adaptive Intensive Behavioral Therapy for Obesity During the Transition to Older Adulthood

Inclusion Criteria: * Male or female sex * all racial and ethnic groups * BMI: 30-50 kg/m2 * age 50-75 years * postmenopausal status for ≥1 y if female sex Exclusion Criteria: * \<3 months stable use of other medications affecting body weight or appetite * \>450 pounds (due to weight limitations of the DXA) * indication or previous diagnosis of sarcopenia * existing kidney disease * current binge eating disorder, anorexia, or bulimia * untreated hyper- or hypothyroidism, cancer (except basal cell), gastrointestinal disorders affecting food intake or nutrient absorption; any other medical condition, as determined by the study physician, precluding a HP diet and/or daily exercise