Obesity is increasingly prevalent, yet the nutritional management remains contentious. It has been suggested that low glycaemic index or load diets may stimulate greater weight loss than higher glycaemic index or load diets or other weight reduction diets.
To assess the effects of low glycaemic index or load diets for weight loss in overweight or obese people.
Trials were identified through The Cochrane Library, MEDLINE, EMBASE, CINAHL and manual searches of bibliographies.
Randomised controlled trials comparing a low glycaemic index or load diet (LGI) with a higher glycaemic index or load diet or other diet (Cdiet) in overweight or obese people.
Two authors independently selected trials, assessed quality and extracted data, including any information provided on adverse effects.
We identified six eligible randomised controlled trials (total of 202 participants). Interventions ranged from five weeks to six months duration with up to six months follow-up after the intervention ceased. The decrease in body mass (WMD -1.1 kg, 95% confidence interval (CI) -2.0 to -0.2, P < 0.05) (n = 163), total fat mass (WMD -1.1 kg, 95% CI -1.9 to -0.4, P < 0.05) (n =147) and body mass index (WMD -1.3, 95% CI -2.0 to -0.5, P < 0.05) (n = 48) was significantly greater in participants receiving LGI compared to Cdiets. The decrease in total cholesterol was significantly greater with LGI compared to Cdiets (WMD -0.22 mmol/L, 95% CI -0.43 to -0.02, P < 0.05), as was the change in LDL-cholesterol (WMD -0.24 mmol/L, 95% CI -0.44 to -0.05, P < 0.05). No study reported adverse effects, mortality or quality of life data.