In a new study published in the Journal PLOS ONE, a meta-analysis of seventeen randomized clinical trials provides insight into the relative benefits of low-carbohydrate and low-fat diets in terms of weight lost, cholesterol and the risk of atherosclerotic cardiovascular disease (ASCVD) events. The seventeen clinical trials used for meta-analysis included a total of 1,797 patients over the age of eighteen who all lacked co-morbidities other than dyslipidemia. Each trial randomly assigned patients to treatment groups and included at least eight weeks of follow-up.
The results of the meta-analysis indicated that both low-carbohydrate and low-fat dietary interventions resulted in weight loss (7.8 and 5.9 kilograms of weight lost respectively). Results, however, favoured the low-carbohydrate intervention for seven of the seventeen trials while none of the trials favoured the low-fat intervention. Overall, patients in the low-carbohydrate intervention groups lost two kilograms more than those in low-fat treatment groups.
Although the low-fat interventions had a greater impact on total cholesterol and LOL-C levels, the low-carbohydrate interventions also had a larger effect in terms of positive HDL-C and triglyceride changes as well as the added benefit of significantly decreasing predicted risk of ASCVD events relative to the low-fat diet (p ≤ 0.3).
In their conclusions the authors of the study suggest that dietary recommendations, currently favouring low-calorie, low-fat, interventions in cases of obesity, should be revisited to consider more thoroughly the benefits of low-carbohydrate diets.
(2015) Dietary Intervention for Overweight and Obese Adults: Comparison of Low-Carbohydrate and Low-Fat Diets. A Meta-Analysis.PLoS ONE 10(10): e0139817. doi: 10.1371/journal.pone.0139817