BACKGROUND Metabolic syndrome (MetS) is highly correlated with obesity and cardiovascular risk, but the importance of dietary carbohydrate independent of weight loss in MetS treatment remains controversial. Here, we test the theory that dietary carbohydrate intolerance (i.e., the inability to process carbohydrate in a healthy manner) rather than obesity per se is a fundamental feature of MetS.METHODS Individuals who were obese with a diagnosis of MetS were fed three 4-week weight-maintenance diets that were low, moderate, and high in carbohydrate. Protein was constant and fat was exchanged isocalorically for carbohydrate across all diets.RESULTS Despite maintaining body mass, low-carbohydrate (LC) intake enhanced fat oxidation and was more effective in reversing MetS, especially high triglycerides, low HDL-C, and the small LDL subclass phenotype. Carbohydrate restriction also improved abnormal fatty acid composition, an emerging MetS feature. Despite containing 2.5 times more saturated fat than the high-carbohydrate diet, an LC diet decreased plasma total saturated fat and palmitoleate and increased arachidonate.CONCLUSION Consistent with the perspective that MetS is a pathologic state that manifests as dietary carbohydrate intolerance, these results show that compared with eucaloric high-carbohydrate intake, LC/high-fat diets benefit MetS independent of whole-body or fat mass.TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT02918422.FUNDING Dairy Management Inc. and the Dutch Dairy Association.
Parker N. Hyde, Teryn N. Sapper, Christopher D. Crabtree, Richard A. LaFountain, Madison L. Bowling, Alex Buga, Brandon Fell, Fionn T. McSwiney, Ryan M. Dickerson, Vincent J. Miller, Debbie Scandling, Orlando P. Simonetti, Stephen D. Phinney, William J. Kraemer, Sarah A. King, Ronald M. Krauss, Jeff S. Volek
Submitter: Shivam Joshi | email@example.com
Authors: Shivam Joshi, Robert J. Ostfeld, Garth Davis, and Michelle McMacken
New York University School of Medicine
Published September 7, 2019
Hyde et al. recently published a crossover trial of 16 obese individuals randomized to four-weeks of consuming a low-, moderate-, or high-carbohydrate diet that appears to have shown that carbohydrate restriction improveed metabolic syndrome independent of weight loss
The predominance of poor-quality carbohydrates in the high-carbohydrate arm of this study appear to nullify the clinical significance of the study findings. It is unfortunate that carbohydrate quality was not assessed or discussed by Hyde et al., especially given the well-known importance of carbohydrate quality in health. It is also noted that several of the authors had financial conflicts of interest with low-carb entities and that funding of the experiment came from “National Dairy Council and the Dutch Dairy Association to The Ohio State University.”
Disclosures: Dr. Ostfeld reported receiving a research grant from the Purjes Foundation.
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