Abstract
BACKGROUND: The purpose of this study was to evaluate the impact of a 60-day low-calorie nutrition-rich diet plan compared to usual care on weight loss, physiological factors, markers of metabolic health, and perceived wellness. METHODS: Overweight or obese adults (N = 60) were randomly assigned to either the active nutrition group (n = 30) or the usual care group (n = 30). The active nutrition plan consisted of two meal replacement shakes, an electrolyte replacement drink, a metabolic support supplement, one whole food meal, and three to five servings of whole food snacks (e.g., vegetables and fruits), which totaled approximately 1200-1600 calories daily. Participants were evaluated at baseline and 30- and 60-day follow-ups for mean changes in anthropometric characteristics, biochemical variables, self-reported feelings of health and well-being, and dietary intake. RESULTS: Of the 60 participants, 49 were women and 11 were men, with a mean age of 38 ± 12 years. Adhering to the active nutrition program for 60 days resulted in a mean weight loss of approximately 6.5 pounds, with a 2-pound weight gain noted for subjects in the usual care group. Related to this, reductions were noted in BMI (p < 0.001), percent fat (p = 0.017), and waist (4 cm, p < 0.001) and hip (3 cm, p < 0.001) circumferences for the active nutrition group but not usual care. Clinically relevant changes were noted for reductions in blood pressure (5 mm Hg) and triglycerides (12 mg/dL) for the active nutrition group. From a subjective perspective, participants in the active nutrition group reported improvements in their self-esteem, motivation, endurance, physical appearance, and strength (p < 0.001). The above was achieved without participants reporting any significant increase in hunger during the intervention, despite the expected reduction in calories. CONCLUSION: Adhering to a semi-structured diet plan that allows for one "regular" whole-food meal daily is well-tolerated and enhances weight loss, physiological factors, and perceived wellness. Follow-up studies with a balanced representation of biological men and women are warranted to determine the longer-term impact of this nutrition program on weight loss and markers of metabolic health.