Effect of Epidemic Intermittent Fasting on Cardiometabolic Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Abstract

Intermittent fasting (IF) has gained attention as a promising diet for weight loss and dysmetabolic diseases management. This systematic review aimed to investigate the effects of IF on cardiometabolic risk factors (CMRFs). A systematic literature search was carried out using three electronic databases, namely PubMed, Embase, and the Cochrane Library, until October 2020. Randomized controlled trials that compared the IF intervention with a control group diet were included. Fourteen effect sizes were expressed as weighted mean difference (WMD) using a fixed-effects model and 95% confidence intervals (CI). Compared to the ones within control groups, participants exposed to the IF intervention reduced their body weight (WMD, −1.78 kg; 95% CI, −2.21 to −1.35; p <0.05), waist circumference (WMD, −1.19 cm; 95% CI, −1.8 to −0.57; p <0.05), fat mass (WMD, −1.26 kg; 95% CI, −1.57 to −0.95; p <0.05), body mass index (WMD, −0.58 kg/m2; 95% CI, −0.8 to −0.37; p <0.05), systolic blood pressure (WMD, −2.14 mmHg; 95% CI: −3.54 to −0.73; p <0.05), diastolic blood pressure (WMD: −1.38 mmHg, 95% CI, −2.35 to −0.41, p <0.05), fasting blood glucose (WMD: −0.053 mmol/L; 95% CI: −0.105 to 0.001; p <0.05), fasting insulin (WMD, −0.8 mIU/L; 95% CI, −1.15 to −0.44; p <0.05), insulin resistance (WMD, −0.21; 95% CI, −0.36 to −0.05; p <0.05), total cholesterol (WMD, −0.10 mmol/L; 95% CI, −0.17 to −0.02; p <0.05), and triglycerides (WMD, −0.09 mmol/L; 95% CI, −0.13 to −0.04; p <0.05). No effects were observed for low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, or glycosylated hemoglobin. This meta-analysis supports the role of IF in improving the component composition of CMRFs, including weight, waist circumference, fat mass, BMI, blood pressure, total cholesterol, triglycerides, fasting insulin, and insulin resistance, compared to a control group diet. Further research on IF interventions should take into account long-term and well-designed administration to draw definitive conclusions.

Intermittent fasting two days versus one day per week, matched for total energy intake and expenditure, increases weight loss in overweight/obese men and women

“…Our finding of significant weight loss and improved body composition outcomes with IF agrees with recent meta-analyses and reviews [ 2 , 5 – 11 ] , although this is not a universal finding [ 6 – 18 ]. Some data also suggest a substantial loss of lean body mass may occur with IF depending on the length and degree of fasting [ 6 , 18 ] which is a common observation during weight loss [ 18 ].…”

Self-Care by Muslim Women during Ramadan Fasting to Protect Nutritional and Cardiovascular Health

“…In addition, we report an association among the observance of Ramadan and the presence of elevated W/Hp ratio and visceral fat, variables which have been shown to be associated with cardiometabolic risk factors [ 29 ]. These results are not in agreement with those of Silveira et al [ 30 ] and Yang et al [ 31 ], who reported that intermittent fasting had positive effects on reducing cardiovascular risk factors in obese women. These differences are probably due to the non-compliance with dietary recommendations by the participants of our study, which have been previously discussed.…”

Effects of Intermittent Fasting in Human Compared to a Non-intervention Diet and Caloric Restriction: A Meta-Analysis of Randomized Controlled Trials

“…This study is a systematic meta-analysis based on RCTs of IF, and it is multi-angle and relatively comprehensive compared with previous meta-analyses ( 76 – 78 ). This study compared IF with CR and non-intervention diets separately, and subgroup analysis was performed according to the patterns of IF and population characteristics.…”