BLACK TEA KOMBUCHA CONSUMPTION: EFFECTS ON CARDIOMETABOLIC PARAMETERS, CONSIDERING THE DIET’S QUALITY OF INDIVIDUALS WITH AND WITHOUT OBESITY

Several foods have been suggested as adjuvants in the treatment of metabolic alterations in obesity. Among them there is kombucha, a fermented beverage obtained by the infusion or extract of Camellia sinensis and sugars, fermented by a microbiologically active Symbiotic Culture of Bacteria and Yeast (SCOBY). Although animal and in vitro studies indicate promising benefits from kombucha consumption, exploring its impact on human health is necessary. Therefore, this study aimed to assess the effect of regular consumption of black tea kombucha on cardiometabolic parameters of individuals with and without obesity. This was a clinical study with eight consecutive weeks duration with forty-six individuals divided into two groups (with and without obesity, n=23/group). Recruitment of participants was carried out in the local community. During the screening, anthropometric and food intake assessments were performed. Individuals who met the inclusion and non-inclusion criteria had to drink 200mL/day of kombucha (produced with 12 g/L of black tea, 50 g/L sucrose, 100 mL/L of a previously produced kombucha batch and 3% SCOBY) and maintain their usual diet and physical activity pattern throughout the study. Participants were assessed before the start of the study and at the end of treatment. In these two moments, Food Frequency Questionnaire, International Physical Activity Questionnaire and collection of blood samples for analysis of cardiometabolic parameters using Mindray/BS-200® Chemistry Analyzer (lipid profile, insulin, glycemia, hepatic enzymes, urea, creatinine), Triglyceride-glucose index (TyG), Fatty Liver index (FLI), Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) were performed. The Dietary Inflammatory Index (DII) and Total Antioxidant Capacity of the diet (DTAC) were calculated to analyze the variation in the participants’ diet quality. A paired t-test (or Wilcoxon) was applied to compare differences between pre-and post-intervention for the same individual. Stratified analyzes were also performed by the group, considering the increase or decrease in the parameters of diet quality. Statistical significance level of 5% (α = 0.05) was adopted for all analyses. A total of 36 individuals completed the study, 20 without obesity and 16 with obesity. After the intervention, participants without obesity showed a significant increase in total cholesterol and alkaline phosphatase, but this was only observed in those who worsened DII and DTAC. In this group, those who increased DII also had an increase in triglycerides, TyG and FLI index. This highlights the urge to combine the beverage’s intake with healthy eating patterns. The individuals with obesity showed a significant decrease in insulin and gamma-glutamyl transferase (GGT) after consumption of black tea kombucha. The enhancement in these parameters remain present after the stratified analyzes of diet quality in this group. The improvement in cardiometabolic parameters after kombucha intake in individuals with obesity can be explained by its complex composition, rich in phenolic compounds and organic acids, that is related to liver detoxification and attenuation of oxidative stress and inflammation presented in obesity. In conclusion, this is the first clinical trial evaluating kombucha intake in humans and demonstrated a positive impact on the metabolic health of individuals with obesity, beyond the importance of maintaining a healthy diet.