Probiotic kefir consumption improves serum apolipoprotein A1 levels in metabolic syndrome patients: a randomized controlled clinical trial

Metabolic syndrome has become a major health hazard of the modern world. Studies investigating the effects of traditional fermented foods on metabolic syndrome are limited. We hypothesized that regular kefir consumption could improve the anthropometrical measurements, glycemic control, lipid profile, blood pressure, and inflammatory status in patients with metabolic syndrome. Sixty-two participants were randomly assigned to receive either 180 mL/d probiotic kefir or unfermented milk for 12 weeks. Dietary intake, anthropometrical measurements, biochemical status, and blood pressure were assessed at baseline and the end of weeks 4, 8, and 12. Serum apolipoprotein A1 concentration increased by 3.4% in the kefir group, whereas it decreased by 2.4% in the milk group in 12 weeks (P = .03). A subgroup analysis for participants with low-density lipoprotein cholesterol (LDL-C) levels >130 mg/dL showed that serum LDL-C and apolipoprotein B concentrations (7.6% and 5.4%, respectively) significantly decreased with kefir consumption compared with the baseline values at the 12th week (P < .05), but not compared with milk consumption (P > .05). Both milk and kefir consumption was associated with lower systolic and diastolic blood pressure compared with the baseline (P < .05). The 12-weeks of kefir administration also decreased serum tumor necrosis factor-α, interleukin 6, interleukin 10, interferon-gamma, and homocysteine concentrations significantly (P < .05). In conclusion, regular dairy consumption as part of a well-balanced diet can provide favorable effects in the management of metabolic syndrome, and probiotic kefir may deserve a special interest among dairy products. This trial was registered at clinicaltrials.gov (NCT03966846).