Comparison of the Mediterranean Diet and Other Therapeutic Strategies in Metabolic Syndrome: A Systematic Review and Meta-Analysis

Abstract

The Mediterranean diet (MD) is one of the healthiest diets, high in fiber, antioxidants, and unsaturated fats. MD improves lipid profiles, reduces inflammation, controls blood pressure, decreases insulin resistance, and enhances the sensitivity to this hormone, lowering the risks of Metabolic syndrome (MS). MS is characterized by central obesity, hypertension, insulin resistance, and dyslipidemia, increasing the risk of cardiovascular disease and type II diabetes. The objective of this study was to know the effectiveness of the MD versus other treatments in patients with MS. A systematic search across multiple databases, Medline, Embase, Web of Science, Scopus, Google Scholar, and Cinahl, was conducted using keywords such as "Mediterranean diet", "Mediterranean food", "eat mediterranean", "Metabolic syndrome", and "x syndrome". A total of 12 studies met the inclusion criteria. Mediterranean diet at different doses versus other diets or other treatments showed significant improvements in clinical parameters, including BMI (mean difference of -0.83 95% CI: -0.93 to -0.74; p < 0.00001),waist circumference (mean difference = -1.81, CI = -2.63 to -0.99, p < 0.00001) triglycerides (mean difference = -22.38, CI = -32.86 to -11.90, p < 0.00001), Glucose (mean difference = -4.28, CI = -7.64 to -0.93, p = 0.005) and, HOMA IR (mean difference = -0.72, CI = -0.78 to -0.65, p < 0.00001), and Insulin resistance (mean difference = -2.98, CI = -3.27 to -2.69, p < 0.00001), all of which improved, Although there were more outcomes, these are the most important changes for patients with metabolic syndrome. MD improves metabolic and cardiovascular health, but study heterogeneity limits the results' generalizability. Because of that, further research is needed to standardize approaches and explore their mechanisms. MD should be part of an optimized strategy that includes education and physical activity. The strength of the evidence was very low according to the GRADE approach. Further research is needed to support the efficacy of the Mediterranean diet in patients with MS.

Keywords: eat mediterranean; mediterranean diet; mediterranean food; metabolic syndrome; x syndrome.

Figure 1

Flow diagram included studies.

Figure 2

Risk of bias summary included studies [2,3,17,18,19].

Figure 3

Diagram risk of bias of studies included [2,3,17,18,19].

Figure 4

Forest plot of body weight in k/g [2,3,17,18,19].

Figure 5

Forest plot of BMI in kg/m² [2,3,18,19].

Figure 6

Forest plot of waist circumference in cm [2,3,17,18,19].

Figure 7

Forest plot of systolic blood pressure (SBP) in mmHg [2,3,17,18,19].

Figure 8

Forest plot of diastolic blood pressure (DBP) in mmHg [2,3,17,18,19].

Figure 9

Forest plot of triglycerides in mg/dL [2,3,17,19].

Figure 10

Forest plot of glucose in mg/dL [2,17,19].

Figure 11

Forest plot of total cholesterol in mg/dL [2,3,17,18,19].

Figure 12

Forest plot of HDL in mg/dL [2,3,17,18,19].

Figure 13

Forest plot of LDL in mg/dL [3,17,18,19].

Figure 14

Forest plot of body fat in kg [18,19].

Figure 15

Forest plot of HOMA-IR [2,3,17].

Figure 16

Forest plot of insulin in μU/mL [2,3,17].