Background: Obesity is a worldwide public health crisis. In the United States, two-thirds of adults are overweight or obese. Obesity is associated with increased all-cause mortality and increased risk of morbidity from coronary heart disease, stroke, type 2 diabetes, hypertension, dyslipidemia, gallbladder disease, osteoarthritis, obstructive sleep apnea, and some cancers. In addition to these health-related implications, obesity also has negative psychosocial, economic, and environmental consequences.

Methods: In this prospective cohort study, our group developed a protocol to assess the impact on behavior and health outcomes of overweight and obese adults. The primary endpoint was weight and BMI, and other endpoints included blood pressure, lipid levels, HbA1c, fasting blood glucose, percent body fat, weight circumference, and hip circumference. A total of 27 adult participants completed this program over four cohorts with minor amendments to each cohort protocol. Participants attended ten weekly group sessions (cohorts I, 2, 3, and 4) followed by five biweekly group sessions (cohorts 2, 3, and 4). Each session introduced nutrition education, physical activity, and behavior modification strategies associated with achieving or maintaining a healthy weight. The program also emphasized mindfulness and portion control and their relationship to hunger, satiety, and long-term health. Self-monitoring was tracked through daily logging in a health passport.

Results: Across four cohorts, 27 participants completed ten weeks of the Learn to Portion protocol. Participants lost an average of 8.12 pounds (P < 0.001) by week 10. There was an average reduction of BMI of 1.40 kg/m2 (P < 0.001). In cohorts three and four (n = 12), waist circumference and blood pressure were measured at baseline and completion. Participants had an average decrease of 2.04 inches in waist circumference (P < 0.001) and a decrease in diastolic blood pressure of 5.58 mmHg (P = 0.012). In cohort four (n = 4), HbA1c and fasting blood glucose measurements were added. Participants had an average decrease in HbA1c of .73% (P = 0.031) and an average decrease in fasting blood glucose of 46.25 mg/dL (P = 0.041). There were no significant changes found in hip circumference, body fat percentage, lipid levels, and systolic blood pressure.

Conclusion: Completing ten weeks of the Learn to Portion protocol resulted in significant weight and BMI reduction. In cohorts 2, 3, and 4, participants continued to lose weight during the five additional biweekly sessions, however, at a decreased rate. This may be due to the increased accountability in weekly group sessions. Larger sample sizes and long-term follow up are needed to assess the overall effectiveness of the program.