Bottom Line: Weight loss over a year was not significantly different for overweight adults who followed a low-fat or low-carbohydrate diet, and neither a person's genetic makeup nor their insulin secretion level was associated with how much weight they lost.
Why The Research Is Interesting: No one diet strategy is consistently better than others for weight loss in the general population. Some studies have suggested variations in people's genetic makeup could make it easier for some to lose weight than others on certain diets. Other studies have reported a person's insulin secretion may explain different weight loss.
Who and When: 609 overweight adults enrolled in a randomized clinical trial from January 2013 through April 2015 with follow-up through May 2016.
What (Study Intervention): Adults followed either a healthy low-fat or healthy low-carbohydrate diet (interventions); weight change at 12 months and a determination about whether there were significant links between the type of diet and a person's genetic makeup, insulin secretion levels and weight loss (outcomes)
How (Study Design): This was a randomized clinical trial (RCT), which allows the strongest inferences to be made about the true effect of an intervention. However, not all RCT results can be replicated in real-world settings because patient characteristics or other variables may differ from those studied in the RCT.
Authors: Christopher D. Gardner, Ph.D., Stanford University Medical School, Stanford, California, and coauthors
A person's genetic makeup or insulin secretion level at the start of the study was not associated with effects on weight loss.
Study Limitation: The generalizability of the findings may be limited because the study was conducted in a geographic area where many people have attained relatively high education levels and/or have the personal resources to allow them high accessibility to high-quality food options.
For more details and to read the full study, please visit the For The Media website.
Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
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