Eight-four participants will be randomized in total; 42 at the University of North Carolina (UNC), 42 at Stanford.
COVID-19 Provisions: Due to impacts of COVID-19, the study was forced to cease recruitment early. 40 subjects were randomized at UNC and 29 were randomized at Stanford, for a total of 69 subjects across sites.
Procedures (methods):
Three distinct dietary approaches will be tested. Dietary approaches are as follows:
Diet 1: hypocaloric, moderate low fat (30% calories from fat) weight management based on the Look AHEAD study Diet 2: hypocaloric, low carbohydrate (15-20% calories from carbohydrate, 59-63% as total fat (<10% saturated fat, at least 37% monounsaturated fat, remaining as polyunsaturated fat) Diet 3: advice to select a healthy Mediterranean dietary pattern with no caloric restriction
Participants will complete measurement visits at baseline (-14 days), 3 mos, 6.5 mos, and 10 mos. All visits transitioned to a virtual format as of 6/2020 due to COVID-19 provisions.
Participants will complete a total of 23 intervention sessions over an approximately 10-and-a-half month period (Eight longer sessions (teleconference) and 15 telephone check-ins)
Participants will be randomized to one of the three diets for a minimum of a three-and-a-half month period. Re-randomization is possible following the 3 month and/or 6.5 month measurement visits. Re-randomization is based on acceptability of diet (self-report), non-severe hypoglycemic events (self-report), and not achieving significant weight change (defined as losing at least 2% of body weight from previous study visit), and worsening glycemic control (increase in Hemoglobin A1c of >/= 0.5% from previous study visit). Re-randomization will occur after the 14-day continuous glucose monitoring (CGM) wear period that will be initiated at each measurement visit.