Comparison of highfat and highprotein diets with

Authors: K A McAuley C M Hopkins K J Smith R T McLay S M Williams R W Taylor J I Mann

Publish Date: 2004/12/23

Volume: 48, Issue: 1, Pages: 8-16

PDF Link

Abstract

A diet low in saturated fatty acids and rich in wholegrains vegetables and fruit is recommended in order to reduce the risk of obesity cardiovascular disease and type 2 diabetes mellitus However there is widespread interest in highfat “Atkins Diet” and highprotein “Zone Diet” alternatives to the conventional highcarbohydrate highfibre approach We report on a randomised trial that compared these two alternative approaches with a conventional diet in overweight insulinresistant womenNinetysix normoglycaemic insulinresistant women BMI 27 kg/m2 were randomised to one of three dietary interventions a highcarbohydrate highfibre HC diet the highfat HF Atkins Diet or the highprotein HP Zone Diet The experimental approach was designed to mimic what might be achieved in clinical practice the recommendations involved advice concerning food choices and were not prescriptive in terms of total energy There were supervised weight loss and weight maintenance phases 8 weeks each but there was no contact between the research team and the participants during the final 8 weeks of the study Outcome was assessed in terms of body composition and indicators of cardiovascular and diabetes riskBody weight waist circumference triglycerides and insulin levels decreased with all three diets but apart from insulin the reductions were significantly greater in the HF and HP groups than in the HC group These observations suggest that the popular diets reduced insulin resistance to a greater extent than the standard dietary advice did When compared with the HC diet the HF and HP diets were shown to produce significantly p001 greater reductions in several parameters including weight loss HF −28 kg HF −27 kg waist circumference HF −35 cm HF −27 cm and triglycerides HF −030 mmol/l HF −022 mmol/l LDL cholesterol decreased in individuals on the HC and HP diets but tended to fluctuate in those on the HF diet to the extent that overall levels were significantly lower in the HP group than in the HF group −028 mmol/l 95 CI 004–052 p=002 Of those on the HF diet 25 showed a 10 increase in LDL cholesterol whereas this occurred in only 13 of subjects on the HC diet and 3 of those on the HP dietIn routine practice a reducedcarbohydrate higher protein diet may be the most appropriate overall approach to reducing the risk of cardiovascular disease and type 2 diabetes To achieve similar benefits on a HC diet it may be necessary to increase fibrerich wholegrains legumes vegetables and fruits and to reduce saturated fatty acids to a greater extent than appears to be achieved by implementing current guidelines The HF approach appears successful for weight loss in the short term but lipid levels should be monitored The potential deleterious effects of the diet in the long term remain a concern

Keywords: