Effectiveness of a Medifast meal replacement program on weight, body composition and cardiometabolic risk factors in overweight and obese adults: a multicenter systematic retrospective chart review study

Abstract

Background: Recent medical guidelines emphasize the importance of actively treating overweight and obesity with diet and lifestyle intervention to achieve ≥ 5% weight loss in a 6-month period. Commercial programs offer one approach provided there is evidence of their efficacy and safety. This study was conducted to evaluate the effectiveness of the Medifast® 4 & 2 & 1 Plan™ on weight loss, body composition and cardiometabolic risk factors in overweight and obese adults.

Methods: A systematic retrospective chart review of 310 overweight and obese clients following the Medifast 4 & 2 & 1 Plan at one of 21 Medifast Weight Control Centers® was conducted. Data were recorded electronically and key data points were independently verified. The primary endpoint was change from baseline body weight at 12 weeks. Within group paired t-tests were used to examine changes from baseline in a completers population. Differences between gender and age subgroups were examined using bivariate t-tests and mixed model regression analyses.

Results: For the primary endpoint at 12 weeks, body weight among completers (n = 185) was reduced by a mean of 10.9 ± 5.6 kg (-10.1%, p < 0.0001), and at 24 weeks (n = 81) mean weight was reduced by 16.0 ± 7.9 kg (-14.3%). At 12 and 24 weeks, 85% and 96% of those remaining on the plan, respectively, had lost ≥ 5% of their baseline body weight. Lean mass was preserved to within 5% of baseline throughout the 24 weeks, and fat mass represented ≥ 80% of the body weight lost from 12 weeks onward. Men, women, seniors (≥ 65 years), and non-seniors (<65 years) all had significant weight reductions with preservation of lean mass. Significant improvements in blood pressure, pulse and waist-to-hip ratio were observed. Mean weight regain among the subset who entered a formal maintenance phase was <2% during an average follow-up of 34 weeks. The meal plan was well tolerated, and program adherence was >85%.

Conclusions: The 4 & 2 & 1 Plan used at Medifast Weight Control Centers was effective for weight loss, preservation of lean mass and improvement in cardiometabolic risk factors. The plan was generally well tolerated in a broad population of overweight and obese adults. #NCT02150837.

Fig. 1

Flow diagram. Chart disposition at week 12 (primary endpoint), week 24 and Final Visit. The Completers population included all individuals that had weight data within the specified visit window. Final Visit represents an individual’s last visit to the MWCC while following the 4 & 2 & 1 Plan. The time of the Final Visit varies by individual, depending on when they discontinued the 4 & 2 & 1 Plan

Fig. 2

Percent change from baseline body weight. Mean (±SD) for the Completers population which included all individuals with weight data at the given visit; sample sizes are designated below the graph. Intention-to-Treat Last Observation Carried Forward (ITT LOCF) values are also shown for 12 and 24-week visits. Final Visit represents an individual’s last visit to the MWCC while on the 4 & 2 & 1 Plan. Absolute weight changes in kg are shown below the graph. Within group changes from baseline body weight using Wilcoxon signed-rank tests are shown: * p < 0.0001

Fig. 3

Proportion of individuals with at least 5 % and at least 10 % reduction in baseline body weight. Analysis of the Completers population which included all individuals with weight data at the given visit; sample sizes are designated below the graph. Final Visit represents an individual’s last visit to the MWCC while on the 4 & 2 & 1 Plan

Fig. 4

Change from baseline body weight, lean body mass and body fat mass. Mean (±SD) for the Completers population which included all individuals with weight data at the given visit; sample sizes are designated below the graph. Within group changes from baseline using Wilcoxon signed-rank tests are shown: * p < 0.0001

Fig. 5

Percent change from baseline in (a) body weight and (b) lean and fat mass by gender. Mean (±SD) for the Completers population which included all individuals with weight data at the given visit; sample sizes are designated below the graph. Final Visit represents an individual’s last visit to the MWCC while on the 4 & 2 & 1 Plan. Significance levels for all within group changes from baseline were p < 0.0001 for body weight and fat mass and p < 0.01 lean mass (not shown). Significance levels for between group comparisons using bivariate t-tests at each time point are shown: *p < 0.05; **p < 0.01; ***p < 0.0001

Fig. 6

Percent change from baseline (a) body weight and (b) lean and fat mass by age group. Mean (±SD) for the Completers population grouped by age (<65 and ≥65 years). Completers included all individuals with weight data at the given visit; sample sizes are designated below the graph. Final Visit represents an individual’s last visit to the MWCC while on the 4 & 2 & 1 Plan. Significance levels for all within group changes from baseline were p < 0.0001 for body weight, p ≤ 0.002 for fat mass and p ≤ 0.05 for lean mass (not shown). Significance levels for between group comparisons using bivariate t-tests at each time point are shown: *p < 0.05; **p < 0.01; ***p < 0.0001