The science behind weight loss diets--a brief review.

BACKGROUND

Controversy surrounds both the Atkins diet and moderate carbohydrate, high protein diets.

OBJECTIVE

This article undertakes a brief review of the evidence for efficacy and possible harmful effects of various popular diets.

DISCUSSION

Low fat diets have been shown to reduce weight at 12 months and have additional benefits of high fibre intake and may reduce the risk of diabetes. However, many people cannot maintain these diets long term so new solutions have been sought. Surprisingly, trials have only appeared over the past 3-4 years evaluating the effects of the Atkins diet, and these have shown weight loss benefits at 6 months, but the benefit is lost by 12 months. Adherence to this regimen is difficult. Problems include constipation from the relatively low fibre intake and a less than expected rise in LDL cholesterol. A moderate carbohydrate, high protein diet has been shown to maintain weight loss at 12 months and beyond, with improvements in cardiovascular risk factors and little risk of long term side effects. Patient choice will depend on dietary preferences and previous experiences with diets. Those with metabolic syndrome might benefit more from carbohydrate restriction.