Effect of the 5:2 Diet on Weight Loss and Cardiovascular Disease Risk Factors in Overweight and/or Obesity: A Systematic Review and Meta-Analysis.

We conducted a systematic review and meta-analysis to evaluate the effects of the 5:2 diet on weight loss and cardiovascular disease (CVD) risk factors in overweight and obese individuals. Databases (PubMed, The Cochrane Library, Web of Science, Embase) were searched for randomized controlled trials of the intervention effects of the 5:2 diet in overweight and obese individuals. The search period was from database establishment to April 2024. RevMan 5.3 and Stata 14.0 were used for the meta-analysis. A total of 20 articles with 1393 participants were finally included. There were 689 participants in the treatment groups and 704 in the control groups. The meta-analysis showed that the 5:2 diet significantly reduces body weight, body mass index, waist circumference, body fat percentage, hip circumference, fat mass, fat-free mass, low-density lipoprotein, systolic blood pressure, and homeostasis model assessment-insulin resistance levels relative to the control group ( < 0.05). However, there was no significant difference in levels of visceral fat, total cholesterol, triglycerides, high-density lipoprotein, diastolic blood pressure, insulin, fasting blood glucose, glycated hemoglobin A1c, and heart rate. Although there were no serious adverse events in the 5:2 diet group, participants in this group experienced mild physical and psychological side effects during the fasting period, which resolved spontaneously after fasting. The 5:2 diet is effective for weight reduction and amelioration of CVD risk factors in overweight/obesity and is safe and feasible. However, the patient's physical condition during the fasting period should be monitored and timely adjustments should be made accordingly.