Adherence
Long-term weight loss (2 years) is equivalent between low-carbohydrate and low-fat diets when both are combined with comprehensive behavioral interventions.
If you are trying to lose weight long-term, do not obsess over whether you must cut carbs or fat. Focus on getting comprehensive behavioral support (counseling, tracking, lifestyle coaching). Both low-carb and low-fat diets resulted in the same amount of weight loss (7%) over two years when behavioral support was included. The specific macronutrient ratio is less important than the behavioral adherence supported by the program.
Both diet groups achieved clinically significant and almost identical weight loss at 1 year (11 kg [11%]) and at 2 years (7 kg [7%]. No differences were found between the groups in weight... over the 2 years of the study.
Why this rating
Randomized controlled trial with a large sample size (n=307) and long duration (2 years), though attrition was high.
Source
Weight and Metabolic Outcomes After 2 Years on a Low-Carbohydrate Versus Low-Fat Diet
Gary D. Foster et al. · Obstetrical & Gynecological Survey · 2010
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