Low-Carbohydrate Diet Better Than Low-Fat Diet to Reduce Cardiovascular Risk Factors and Cause Weight Loss
FREE PREVIEW. AAFP members and paid subscribers: Log in to get free access. All others: Purchase online access.
FREE PREVIEW. Purchase online access to read the full version of this article.
Am Fam Physician. 2015 Feb 15;91(4):262.
Is a low-fat or a low-carbohydrate diet more effective in causing weight loss and improving cardiovascular disease risk?
More than 40 years ago, Dr. Robert Atkins wrote his first book advocating for a low-carbohydrate diet to cause and sustain weight loss. This study (of mostly women) found that a low-carbohydrate diet—though not as severe a diet as the Atkins approach—caused an average 3.5 kg (7.7 lb) greater weight loss than a low-fat diet. Both diet approaches were undertaken without any caloric restriction; in other words, these were low-carbohydrate and low-fat, not low-calorie, diets. (Level of Evidence = 1b–)
The 148 participants were volunteers from the general public: 88% were women and 50% were black. They were randomized, concealed allocation uncertain, to a diet of fewer than 40 g of carbohydrates per day (the Atkins diet suggests fewer than 20 g per day) or a diet aimed to keep fat to less than 30% of daily energy intake, which is in line with the diet recommended by the National Cholesterol Education Program in the United States. Neither diet included a specific calorie goal.
Participants in both groups received significant counseling consisting of individual weekly sessions with a dietitian for the first four weeks followed by small-group counseling sessions every other week for the next five months. At 12 months, the low-carbohydrate diet group lost an average of 3.5 kg more than the low-fat diet group (−5.3 vs. −1.8 kg [−11.7 vs. −4.0 lb]). They also had greater reductions in fat mass and higher gains in lean mass. Although total cholesterol levels did not markedly change in either group, high-density lipoprotein levels increased significantly more in the low-carbohydrate group, and triglyceride levels decreased significantly more in that group, as well. Blood pressure, glucose levels, and insulin levels were not different between the groups.
Study design: Randomized controlled trial (nonblinded)
Funding source: Government
Setting: Outpatient (any)
Reference: Bazzano LA, Hu T, Reynolds K, et al. Effects of lowcarbohydrate and low-fat diets: a randomized trial. Ann Intern Med.. 2014; 161( 5): 309– 318.
POEMs (patient-oriented evidence that matters) are provided by EssentialEvidence Plus, a point-of-care clinical decision support system published by Wiley-Blackwell. For more information, please see http://www.essentialevidenceplus.com. Copyright Wiley-Blackwell. Used with permission.
For definitions of levels of evidence used in POEMs, see http://www.essentialevidenceplus.com/product/ebm_loe.cfm?show=oxford.
To subscribe to a free podcast of these and other POEMs that appear in AFP,search in iTunes for “POEM of the Week” or go to http://goo.gl/3niWXb.
This series is coordinated by Sumi Sexton, MD, Associate Medical Editor.
A collection of POEMs published in AFP is available at http://www.aafp.org/afp/poems.
Want to use this article elsewhere? Get Permissions
More in AFP
MOST RECENT ISSUE
Dec 1, 2016
Access the latest issue of American Family Physician