Efficacy and safety of a specific commercial high-protein meal-replacement product line in weight management: meta-analysis of randomized controlled trials

Abstract

Background

Protein is suggested to be the nutrient providing the most satiety and is frequently used in meal-replacement products to achieve weight loss. Commercial products such as Herbalife high-protein (HP) products have been studied in various clinical trials, but controversy remains regarding their efficacy and safety.

Methods

We searched the PubMed, Center for Clinical and Translational Research (CCTR), and Google Scholar databases for randomized controlled trials of Herbalife HP products used as meal replacement (MR) published through July 2019 in peer-reviewed journals. We reviewed changes in efficacy and safety-related outcomes in treatment and control groups, and we estimated the pooled standardized mean difference (SMD) and corresponding 95% confidence intervals (CIs) with a DerSimonian and Laird random-effects method.

Results

By pooling data from nine identified studies (934 participants: 463 in treatment groups and 471 in control groups), we found that participants who consumed HP products experienced significantly larger decreases in body weight (SMD = −0.24; 95% CI: −0.37 to −0.10), body mass index (SMD = −0.31; 95% CI: −0.50 to −0.11), and fat mass (SMD = −0.37; 95% CI: −0.65 to −0.09) than did individuals consuming control diets. Concerning safety outcomes, the participants in the treatment group had a significantly larger decrease in aspartate aminotransferase (SMD = −0.23; 95% CI: −0.42 to −0.03). There were no significant between-group differences in alanine aminotransferase or creatinine. However, blood urea nitrogen levels increased in both groups, with a significantly larger increase in the treatment group (SMD = 0.53; 95% CI: 0.15 to 0.92).

Conclusions

Herbalife HP MR products appear effective and do not evidence significant risk in reducing body weight.

Keywords:

• fat-free mass
• high-protein diet
• meal replacement
• waist circumference
• weight loss

Acknowledgments

The study was funded by Herbalife International, USA. Herbalife International had no control over study execution or manuscript preparation, including data analysis, data interpretation, or manuscript drafting.

The authors’ responsibilities — DA and PX: designed the project; YZ and PX: conducted literature searching, study selection, data extraction, and data analysis, as well as prepared the tables and figures; YZ and PX: performed data analysis; XC: verified data extraction and analysis; YZ, PX, and DA: interpreted the results, and drafted the manuscript; DA: provided administrative support and supervised the whole process. All authors: critically reviewed the manuscript for important intellectual contents and approved the final version.

Conflict of interest: YZ, PX, and XC have none to declare. Dr. Allison has received personal payments or promises for the same from: American Society for Nutrition; American Statistical Association; Biofortis; California Walnut Commission; Columbia University; Fish & Richardson, P.C.; Frontiers Publishing; Henry Stewart Talks; IKEA; Indiana University; Laura and John Arnold Foundation; Johns Hopkins University; Law Offices of Ronald Marron; MD Anderson Cancer Center; Medical College of Wisconsin; National Institutes of Health (NIH); Sage Publishing; The Obesity Society; Tomasik, Kotin & Kasserman LLC; University of Alabama at Birmingham; University of Miami; Nestle; WW (formerly Weight Watchers International, LLC). Dr. Allison is an unpaid member of the International Life Sciences Institute North America Board of Trustees. Dr. Allison’s institution, Indiana University, has received funds to support his research or educational activities from: NIH; Alliance for Potato Research and Education; American Federation for Aging Research; Dairy Management Inc; Herbalife; Laura and John Arnold Foundation; National Cattlemen’s Beef Association, Oxford University Press, the Sloan Foundation, The Gordan and Betty Moore Foundation, and numerous other for-profit and nonprofit organizations to support the work of the School of Public Health and the university more broadly.