The Impact of the Ketogenic Diet on the Lipid Profile in Adults: A Comprehensive Review and Meta-Regression Analysis...

The impact of the ketogenic diet (KD) on lipid metabolism remains inconclusive. To address this gap, we conducted a meta-regression analysis of randomized controlled trials to evaluate the overall influence of KD on lipid profile parameters in adults.

A comprehensive search of 5 major electronic databases was carried out using predefined keywords to identify randomized controlled trials assessing the effects of KD on lipid outcomes. Pooled weighted mean differences with 95% confidence intervals were calculated employing a random-effects model.

Sixty-two studies were analyzed. The meta-analysis results from the included randomized controlled trials indicated a significant decrease in triglyceride levels (weighted mean difference [WMD]: -19.96 mg/dl, 95% CI: -26.10 to -13.81) and the triglyceride/high-density lipoprotein-cholesterol (HDL-C) ratio (WMD: -0.31, 95% CI: -0.49 to -0.12), despite a notable increase in HDL-C (WMD: 3.61 mg/dl, 95% CI: 1.44 to 5.57), low-density lipoprotein-cholesterol (LDL-C) (WMD: 8.49 mg/dl, 95% CI: 5.45 to 11.52), and total cholesterol (WMD: 8.14 mg/dl, 95% CI: 3.41 to 12.88) concentrations following KD compared to the control group. However, LDL-C levels increased by 8.49 mg/dL, which may carry potential adverse implications. Furthermore, the findings indicated a linear correlation between alterations in HDL-C and the duration of KD intervention.

The ketogenic diet significantly improves triglycerides and HDL-C but also leads to modest increases in LDL-C. Given the lack of long-term cardiovascular outcome data, these findings should be interpreted with caution.