Kefir and Metabolic Syndrome

The Effect of Regular Kefir Consumption on Metabolic Syndrome Parameters, Inflammatory Response, and Gut Microbiota: A Parallel-Group, Randomized, Controlled Clinical Study

Hacettepe University, Turkey Council of Higher Education Teaching Stuff Training Program, Ege University

Metabolic syndrome is a cluster of metabolic disorders which increases the risk for diabetes and cardiovascular disease. In recent years, research has shown that probiotics may have positive effects on metabolic syndrome components. Although several health-promoting effects of kefir, have been suggested, there is limited evidence for its potential effect on metabolic syndrome. Therefore, it is necessary to clarify the effects of kefir on metabolic disorders including obesity, dyslipidemia, diabetes, and hypertension. To address the research gap, this study aimed to investigate the effects of daily kefir consumption on metabolic syndrome components, inflammatory response and gut microbiota composition in adults with MetS. The study was planned as a randomized, controlled, parallel design and completed with a total of 62 individuals who were diagnosed with metabolic syndrome according to the International Diabetes Federation (IDF) criteria. Participants were randomized into two groups and received daily 180 ml of kefir (n=31) or milk (as control) (n=31) for 12 weeks. Participants were assessed at baseline, week 4, week 8, and week 12 and at all controls dietary records, anthropometric measurements, and blood samples were collected. At baseline and 12th-week fecal samples were also collected in order to analyze gut microbiota composition.

There were two experimental groups. The kefir group, that received orally kefir, and the control group received milk

Kefir group received one bottle of kefir (180 ml) daily for 12 weeks. Microbial composition of the kefir included Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. cremoris, Lactococcus lactis ssp. diacetylactis, Leuconostoc mesenteroides ssp. cremoris, Lactobacillus kefyr, Kliyveromyces marxianus, and Saccharomyces unisporus.

Determine the profile of gut flora (% abundance of various bacterial phyla, families, genera and species)

Measurement of serum cytokines levels (high sensitive serum C- reactive protein ,TNF-α, IL-6, IL-10 ve IFN-γ)

Inclusion Criteria: 18-65 years old subjects Subjects diagnosed with metabolic syndrome according to the International Diabetes Federation (IDF) criteria. Exclusion Criteria: Existence of lactose intolerance Existence of type 1 diabetes Existence of abnormal thyroid hormone levels Existence of chronic gastrointestinal system disease Existence of cancer Existence of severe liver disease Existence of kidney insufficiency Existence of immunodeficiency Taking medication to regulate blood glucose (except metformin) or lipid levels Taking antibiotics prior to one month of the study Consuming regular probiotic food or supplement Taking supplement which may affect the metabolic outcomes such as prebiotic or omega-3 Dieting for weight loss or for another disease Being pregnant and breastfeeding.

Bellikci-Koyu E, Sarer-Yurekli BP, Karagozlu C, Aydin-Kose F, Ozgen AG, Buyuktuncer Z. Probiotic kefir consumption improves serum apolipoprotein A1 levels in metabolic syndrome patients: a randomized controlled clinical trial. Nutr Res. 2022 Jun;102:59-70. doi: 10.1016/j.nutres.2022.02.006. Epub 2022 Mar 7.