Reference: Mancini, J.G., et al., Systematic Review of the Mediterranean Diet for Long-Term Weight Loss. Am J Med, 2016. 129(4): p. 407-415 e4.
One-sentence summary: The Mediterranean diet was efficacious for long-term weight loss in overweight or obese individuals compared with low-fat diets, but not compared with other diets (a low carbohydrate diet or the American Diabetes Association diet).
Study type: A systematic review of 5 RCTs on the Mediterranean diet and weight loss over 12 months or more.
Diet: The Mediterranean diet (6 treatment arms) vs. a low fat diet (4 treatment arms), a low-carbohydrate diet (1 treatment arm), or the American Diabetes Association diet (1 treatment arm).
Outcomes measured: Primary outcomes were weight loss, BMI and waist circumference.
Population: Adults with overweight or obesity who were trying to lose weight. Only 1 RCT assessed the effects of the Mediterranean diet in overweight but otherwise healthy individuals. The remaining 4 RCTs included participants with type 2 diabetes (3 trials), coronary heart disease (1 trial), or a recent myocardial infarction (1 trial). Country of origin was not specified by the authors.
A Mediterranean diet at 12 months resulted in:
Quality assessment: The quality of trials was assessed using the Cochrane Collaboration’s tool for assessing the risk of bias in RCTs. Most trials had a low or unclear risk of bias for sequence generation (5 trials), allocation concealment (4 trials), and blinding (4 trials).
The bottom line: The Mediterranean diet resulted in weight loss and a reduction in BMI and waist circumference over the longer-term in overweight or obese individuals. It was more efficacious than a low fat diet, but not compared to other diets.
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