ABSTRACT: Abstract Objectives To determine if greater weight loss and improvement in metabolic outcomes could be achieved with twice daily consumption of a proprietary supplement shake containing high protein and fiber (HPF) as compared to an isocaloric low protein, lower fiber placebo (P). Methods In an independently conducted randomized, double-blind, placebo-controlled, multi-center clinical trial, healthy overweight and obese adults (n = 206, BMI 27–35 kg/m2, 70% Female) were equally assigned to HPF or P. All participants were instructed to follow a 500-calorie deficit diet from estimated daily energy requirements using a dietary exchange program and were asked to consume HPF or P 30 min before breakfast and lunch for 12 weeks. The supplement was a commercially available product composed of protein, fruit, vegetable, and plant powders, as well as vitamins, minerals, pre-, and probiotics. Body weight, body composition, and blood samples were collected at days (D) 0 and 84. Statistics were conducted by ANCOVA or repeated measure ANCOVA modeling using sex and baseline values as covariates, with time and treatment as within- and between-subject variables, respectively. Per protocol analyses were included for the 133 adults who completed the study. Results Weight loss occurred throughout the study in both groups. HPF had greater weight loss at D 84 vs P (–4.0% vs ?2.2% body weight, respectively; P < 0.05). Total cholesterol, LDL, and oxidized LDL decreased to a greater extent following HPF at D 84 (P < 0.05 vs D 0 and vs P), with no change in HDL cholesterol. The increase in serum adiponectin from D 0 to D 84 was greater in HPF vs P (P < 0.05) with no change in leptin. Percent body fat tended to decrease throughout the study in both groups (HPF: ?1.44%, P: ?1.27%; P = 0.056) with no differences between groups. There were no clinically relevant changes in assessed safety outcomes in either group. Conclusions A HPF supplement taken as a preload before breakfast and lunch improved weight loss and metabolic outcomes such as total, LDL and oxidized LDL cholesterol compared to a calorie-matched placebo. This study suggests nutrient factors other than calorie reduction alone influence the success of a weight loss regimen, potentially including nutrient density, protein and fiber content. This trial was registered at clinicaltrials.gov as NCT03057873. Funding Sources This study was funded by Beachbody, LLC.
