Comparison of dietary macronutrient patterns of 14 popular named dietary programmes for weight and cardiovascular risk factor reduction in adults: systematic review and network meta-analysis of randomised trials

This analysis (121 trials; n=21,942) found low carbohydrate (e.g. Atkins, Zone), low fat (e.g. Ornish) and moderate macronutrient (e.g. DASH, Mediterranean) diets resulted in modest reduction in weight and blood pressure at 6 months; such benefits largely disappeared at 12 months

SPS commentary:

Although some differences between the different diets (e.g. in effects on LDL and HDL cholesterol) were noted, the authors say they were ‘generally trivial to small’; this suggests that people can choose the diet they prefer, without concern over the magnitude of the benefit.

British Medical Journal