Low Carb vs. Low Fat for Weight Loss

Apparently, 14 clinical trials comparing a low carb diets with low fat diets with statistically significant results have been published between 2003 and 2008. In all 14 trials, those on low carb diets lost significantly more weight than those on low fat diets. The author is careful to point out that he only selected studies that statistically compared one diet to another, and that the "low carb" diets were truly low carb. (Some studies claiming to compare low fat with "low carb" are not really low carb, as there are more than 30% of calories from carbohydrates. In a true low carb diet, carbs are usually 5 to 10% of calories).

The author of the article summarizing this list has given permission to copy it onto other blogs, so I am taking advantage of his generosity. Here are the studies, complete with links, for you data junkies out there.


Randomized controlled trials showing significantly more weight loss with low carb diets:

• Brehm BJ, et al. A Randomized Trial Comparing a Very Low Carbohydrate Diet and a Calorie-Restricted Low Fat Diet on Body Weight and Cardiovascular Risk Factors in Healthy Women. J Clin Endocrinol Metab 2003;88:1617–1623.
• Samaha FF, et al. A Low-Carbohydrate as Compared with a Low-Fat Diet in Severe Obesity. N Engl J Med 2003;348:2074–81.
• Sondike SB, et al. Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. J Pediatr. 2003 Mar;142(3):253–8.
• Aude YW, et al. The National Cholesterol Education Program Diet vs a Diet Lower in Carbohydrates and Higher in Protein and Monounsaturated Fat. A Randomized Trial. Arch Intern Med. 2004;164:2141–2146.
• Volek JS, et al. Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutrition & Metabolism 2004, 1:13.
• Yancy WS Jr, et al. A Low-Carbohydrate, Ketogenic Diet versus a Low-Fat Diet To Treat Obesity and Hyperlipidemia. A Randomized, Controlled Trial. Ann Intern Med. 2004;140:769–777.
• Nichols-Richardsson SM, et al. Perceived Hunger Is Lower and Weight Loss Is Greater in Overweight Premenopausal Women Consuming a Low-Carbohydrate/High- Protein vs High-Carbohydrate/Low-Fat Diet. J Am Diet Assoc. 2005;105:1433–1437.
• Gardner CD, et al. Comparison of the Atkins, Zone, Ornish, and learn Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women. The a to z Weight Loss Study: A Randomized Trial. JAMA. 2007;297:969–977.
• Shai I, et al. Weight loss with a low-carbohydrate, mediterranean, or low-fat diet. N Engl J Med 2008;359(3);229–41.
• Krebs NF, et al. Efficacy and Safety of a High Protein, Low Carbohydrate Diet for Weight Loss in Severely Obese Adolescents. J Pediatr 2010;157:252-8.
• Summer SS, et al. Adiponectin Changes in Relation to the Macronutrient Composition of a Weight-Loss Diet. Obesity (Silver Spring). 2011 Mar 31. [Epub ahead of print]
• Daly ME, et al. Short-term effects of severe dietary carbohydrate-restriction advice in Type 2 diabetes–a randomized controlled trial. Diabet Med. 2006 Jan;23(1):15–20.
• Westman EC, et al. The effect of a low-carbohydrate, ketogenic diet versus a low- glycemic index diet on glycemic control in type 2 diabetes mellitus. Nutr. Metab (Lond.)2008 Dec 19;5:36.
• Dyson PA, et al. A low-carbohydrate diet is more effective in reducing body weight than healthy eating in both diabetic and non-diabetic subjects. Diabet Med. 2007 Dec;24(12):1430-5.