Effects of a 12-week Plant-Based Diet Program on Obese and Overweight Adults in Rural Michigan
Authors:   ,   Andrews University, Larcher Nadine 
Published: June 2023

Background Overweight and obesity among adults are a rising epidemic in the U.S. Obesity is a risk factor for many chronic diseases and impacts morbidity and mortality. Despite our high-tech medical care system in the U.S., we are losing the war on obesity due to not addressing the underlying problems. These include unhealthy lifestyles and an unhealthy diet. A growing body of research studies has shown that adopting a low-fat whole food plant-based diet (WFPBD) regime consisting of whole grains, fruits, vegetables, legumes, and no animal-based products is an effective measure to counteract the rising pandemic of chronic diseases related to obesity. Purpose The purpose of this project was to examine the effects of a WFPBD on overweight and obese adults residing in northern Michigan. The project objectives were to examine if a 12-week online program on a plant-based diet would improve body mass index (BMI), waist circumference (WC), blood pressure (BP), fasting blood glucose (FBG), and serum lipid levels in this population and to determine if participants' self-efficacy and intake of plant foods would improve post-WFPBD. -- Methods. This project used a quasi-experimental one-group pre-test post-test design. Forty-three individuals started the program, and 35 completed the requirements. The mean age for participants was 54.92 (SD=12.09) (range 34-75 years). For gender, 10 (23.3%) were male, and 32 (76.2%) were female. Biometric measurements, including weight, BMI, BP, WC, total cholesterol, LDL, HDL, triglycerides, and FBG, were taken before and after the program. Participants were also asked to complete a self-efficacy questionnaire before and after the program and a dietary questionnaire at baseline, week four, week eight, and post-intervention. The intervention was entitled The Eat Well, Live Well Program. Through a 12-week evidence-based online lifestyle educational intervention, participants were taught the principles of a WFPBD and how to apply these measures to lose weight, lower their risk factors for obesity-related diseases, and manage obesity-related problems. Results The results of the biometric measurements indicated significant reductions in BMI of 1.09 (t(34) = 5.583, p < .001, d=0.944), weight of 7.21 pounds (t(34) = 6.370, p < .001, d=1.077), WC of 2.01 inches (t(34) = 7.781, p < .001, d=1.315), FBG of 4.94 mg/dL (t(34) = 2.174, p = .018), total cholesterol of 13.971 mg/dL (t(34) = 2.248, p = .016, d=0.380), LDL of 10.03 mg/dL (t(31) = 1.784, p = .042, d=0.315), and triglyceride levels of 14.77 mg/dL (t(34) = 1.744, p = .045, d=0.295). Results for HDL levels, systolic blood pressure (SBP), and diastolic blood pressure (DBP) were not statistically significant. There was a mean increase in self-efficacy scores of 3.810, which was not statistically significant (p=.05). Results of the Mediterranean food questionnaire showed a significant difference between baseline and week four (p<0.01), between baseline and week eight (p<0.01), and between baseline and post-intervention (p<0.01). There were no significant differences when comparing weeks four, eight, or post-intervention to other weeks aside from baseline. Conclusion This project demonstrated significant reductions in total cholesterol, LDL, triglycerides, FBG, BMI, weight, and WC. The results of this project indicate that any change in the direction of a WFPBD is a good change and may be associated with a decreased risk for obesity and chronic diseases.