Did We Lose Weight Summary:
This joint study by researchers from Johns Hopkins University School of Medicine, Weill Medical College of Cornell,
and other prestigious educational institutions
in the US found
meal replacements to be very effective in
achieving weight loss, lower body fat, and overall improvement
health (lower cholesterol levels and blood pressure) among
What does this mean to you?
If you are considering a meal replacement weight
loss program, this study proves the
effectiveness of these programs. Meal replacements
also deliver superior
weight loss results and nutrition than
diets. In addition, since meal replacement
programs are easier to use and follow, you have a better
chance of staying through the duration of a program — until
you reach your weight loss goal or for
Of the top meal replacements in the market
today, we found
Medifast to be the best. If you would like
to learn more about this diet program, feel free
to read our Medifast
Study Background and Methodology. The study is a controlled randomized parallel group 40-week trial to compare the intermediate-term weight-loss efficacy of two patterns of prescribed calorie restriction using a soy-based meal replacement product. Subjects were randomly assigned to a sequence of either 12 weeks at 1200 kcal/day, 16 weeks at 1500 kcal/d and 12 weeks at 1800 kcal/d (the 12/15/18 diet group), or 28 weeks at 1500 kcal/d and 12 weeks at 1800 kcal/d (the 15/18 diet group). Secondary outcomes were body fat, waist circumference, serum lipid concentrations and blood pressure.
Overweight/obese persons with body mass index (BMI; kg/m2) between 28 and 41 (men: n = 13 and women: n = 86) between the ages of 35 and 65 were enrolled in this trial. Exclusion criteria were: weight loss >5 kg in the past 3 months, use of weight loss medication within the past 6 weeks, scores above the 90th percentile on the Brief Symptom Inventory (BSI, a screening measure of general psychological functioning), presence of disease not believed to be at least partially the result of obesity and treatable by weight reduction, medical or psychological contraindications as determined by study investigators, or known hypersensitivity to any of the ingredients of the formula, including but not limited to, soy protein. The study was approved by the IRB at St. Luke's/Roosevelt Hospital, and all subjects provided written informed consent. Prior to participation and acceptance into the program, subjects were deemed medically fit for safe weight loss through a physical examination. After meeting eligibility criteria, candidates were randomized via computer-generated pseudo random numbers at a 1:1 allocation ratio, without regard to race or sex, to one of two treatment groups described below. Thirty-seven subjects enrolled in this trial had formerly been the control group for a 12-week weight loss study which has been described elsewhere . An additional 62 were newly recruited from clinic records and advertisements in the local press.
Ninety-nine subjects were randomized, 50 into the 12/15/18 treatment group and 49 into the 15/18 treatment group. Sixty-one subjects remained after 12 weeks, 42 after 24 weeks, and 30 subjects completed the 40-week trial.
Key Results. This 40-week weight loss trial comparing two distinct patterns of caloric restriction indicated that, on the whole, both protocols were associated with fairly similar magnitudes of beneficial weight loss, as well as similar beneficial changes on health variables. When newly recruited subjects and previous control subjects were pooled there were no significant differences between the calorie restriction groups on weight loss, body fat, total cholesterol, HDL cholesterol and triglycerides at each assessment. Significant differences were observed on WC, LDL cholesterol and blood pressure at various assessment points, and, in these cases, the magnitude of the change was greater for the 12/15/18 group.
The exact implications of the observed cholesterol changes are not immediately apparent because of the simultaneous variation in the total and fractions of cholesterol. Decreases seen in total and LDL levels, which would be interpreted as beneficial, are accompanied by a decrease in HDL, which is known to have a protective effect. One resolution is to use a combination measure such as the HDL/total cholesterol index which has been shown to have stronger associations with coronary heart disease than the individual cholesterol components. In this study the HDL/total cholesterol index was significantly improved over baseline in both groups at every time point.
The results of the mixed models were generally consistent: no matter the health variable in question, subjects tend to have a desirable change in the outcome over time, with the largest changes occurring earlier in the trial. Moreover, subjects with less desirable baseline values (e.g., larger waist circumference) tended to show a change of greater magnitude. Finally, subjects in the 12/15/18 group tended to experience, on some measures, additional change on the outcome versus subjects in the 15/18 group.
There was also a tendency for newly recruited subjects to show greater improvements than subjects who had previously served as controls. The IN1 variable was positive in all models although it only occasionally reached conventional significance levels. This may be the result of the weight loss that had previously occurred in the control group, making it more difficult for subjects to lose additional weight in this follow-up study. Study designs which call for re-randomization of subjects who previously served as controls should consider the possibility of diminished effects.
This study has limitations. First, this 40-week trial did not include a non treatment control condition. Thus, we were unable to evaluate the effects of the two treatments compared with the absence of treatment. In this regard, however, our previous study (10) demonstrated that, over 12-weeks, assignment to the soy-based meal replacement program caused reductions in weight and improvements on health variables compared with receiving only dietary advice. In addition, the outcome measures are substantially improved during and at the end of the study period compared to baseline values. Nonetheless, the absence of a no treatment control group in this trial limits the conclusions that can be drawn.
Second, because of the duration of the study and the minimal intervention offered, only 30% of the subjects completed the entire trial. Although high attrition rates are not uncommon even in shorter-term weight loss trials , it raises the possibility that our results may not be representative of all persons who take part in this, or a similar, weight loss protocol.
Conclusion. This 40-week trial indicates that a reduced calorie deficit diet that includes a soy-based meal replacement shake produces significant changes on body weight and on selected health variables. Adherence to the prescribed degree of soy product usage remained relatively constant throughout, except for the final month. Greater adherence was associated with greater weight loss during the trial. Finally, both patterns of caloric restriction were effective in promoting weight loss and were associated with comparable levels of weight loss over the course of the trial. In general, this was also the case with regard to important health variables such as blood pressure and serum lipid concentrations.
"Results of soy-based meal replacement formula on weight, anthropometry, serum lipids & blood pressure during a 40-week clinical weight loss trial,"
Kevin R Fontaine, Dongyan Yang , Gary L Gadbury, Stanley Heshka , Linda G Schwartz , Radha Murugesan , Jennifer L Kraker , Moonseong Heo , Steven B Heymsfield and David B Allison
Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Department of Biostatistics & Clinical Nutrition Research Center, University of Alabama at Birmingham, Birmingham, AL, United States; Department of Mathematics and Statistics, University of Missouri – Rolla, United States; Obesity Research Center, St. Luke's/Roosevelt Hospital, Institute of Human Nutrition, Columbia University College of Physicians & Surgeons, New York, New York, United States; Weill Medical College of Cornell, White Plains, New York, United States
Nutrition Journal 2003, 2:14doi:10.1186/1475-2891-2-14