Effect of a carbohydrate-restricted dietary intervention on LDL particle size and number in adults in the context of weight loss or weight maintenance: a systematic review and meta-analysis

American Journal of Clinical Nutrition, nqab212, https: //doi.org/10.1093/ajcn/nqab212

Commentary

This study was conducted as a systematic review to investigate the association between carbohydrate restriction and LDL particle size and LDL-P.

LDL particle size and number (LDL-P) have been recognized as emerging risk factors for lipids. A non-systematic review suggests that a tendency for diets to be low in carbohydrates may result in larger LDL particle size.

The study searched six electronic databases on January 4, 2021, for randomized trials of any length that reported on dietary carbohydrate restriction (intervention) compared with increased carbohydrate intake (control).

The result was a compilation of 38 randomized trials involving a total of 1785 participants. We observed an increase in LDL peak particle size and a decrease in LDL-P with a carbohydrate-restricted diet; the effect of carbohydrate-restricted dietary intervention on LDL peak particle size was partially explained by differences in weight loss between intervention groups, and exploratory analysis revealed a shift from small high-density to larger LDL subclasses. An exploratory analysis revealed a shift from a small high density to a larger LDL subclass.

There was no statistically significant association between the carbohydrate-restricted diet intervention and mean LDL particle size (SMD = 0.20; 95% CI: -0.29, 0.69; P = 0.37). These available evidences showed that carbohydrate-restricted dietary interventions increased LDL peak particle size and decreased the number of total, small LDL particles.