Weight loss intervention trial comparing intermittent low carbohydrates versus continuous Mediterranean diet

Abstract

Intermittent low carbohydrate diet (ILCD) may result in greater overall weight loss and body fat % than a daily restricted Mediterranean diet (DRMD). Overweight women (BMI 25kg/m2 - <32.4kg/m2) (n 85) aged 25- 65 years on healthy women not on any medication were randomised to a continuous 25% daily energy restriction in both groups, to either a DRMD (7d/ week) or ILCD (<20% carbohydrates for 2d/ week consecutively then follow a DRMD 5d/week) for a twelve week weight- loss period. Body fat % reduced with the DRMD (median -2.9kg (95% CI: -2.6, -2.1) and the ILCD diet (median -2.9kg (95% CI: -2.3, -2.0). Reductions were not significantly different between the two diets. Reductions in weight loss in the DRMD (median -1.7kg (95% CI: -1.6, -0.1) and ILCD (median -1.0kg (95% CI: -1.5, -1.0) between groups also showed no statistical difference. Waist reduction in the DRMD (mean -5.7cm (95% CI: -5.8, - 40 5.5) and in the ILCD (mean -5.6cm (95% CI: -3.6, -5.8) with greater reductions in the DRMD compared to the ILCD group was significant (mean -0.1cm (95% CI: -2.2, -0.3, P= 0.04). Hip reduction in the DRMD (median -4.3cm (95% CI: -4.6, -4.2) and in the ILCD (median -3.7cm (95% CI: -4.6, -1.2) with greater reductions in the DRMD compared to ILCD group was also significant (median -0.6cm (95 CI: -0.0, -3.0, P= 0.02). Both diets overall are just as effective and there is no evidence that ILCD is superior for fat loss than a DRMD. In the short term DRMD is comparable to ILCD with respect to waist (P = 0.04) and hip circumference (P = 0.02). Drop out rate was low (11%) compared to previous studies (22%- 25%). Long- term studies into the effectiveness and adherence to the ILCD diet are warranted and rejects both hypotheses.