NCT07522372

Evaluation of the Effect of Kefir Consumption

Evaluation of the Effect of Kefir Consumption on Urinary and Salivary Levels of Metabolites Such as BCAAs and on Biomarkers of Well-being

• Status: Active Not Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 66 (estimated)
• Sponsor: Sys2Diag · Other Government
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Accepted

Summary

Many societies traditionally use fermentation as a means of producing beverages, whose microbial transformation is spontaneously triggered or facilitated by the addition of a catalyst (yeasts, bacteria). Kefir is a traditional beverage belonging to the latter category. It is a probiotic that is supposed to modify the intestinal microbiota and the metabolites produced. Links between kefir and metabolic syndromes (insulin resistance, etc.) have also been described in animal models. Very few clinical studies have evaluated the effects of kefir in humans. A 'positive feeling' has also been described by people who consume kefir. Kefir could therefore have an effect on people's well-being.

Detailed description

Many societies traditionally use fermentation as a means of producing beverages, whose microbial transformation is spontaneously triggered or facilitated by the addition of a catalyst (yeasts, bacteria). Kefir is a traditional beverage belonging to the latter category. This beverage is obtained by inoculating sugared water, supplemented with fresh and dried fruits, with translucent grains composed of symbiotic microorganism communities (mainly lactic acid bacteria and yeasts). Kefir conveys an image of a 'healthy' beverage, naturally sparkling and non-alcoholic (alcohol content \<1%), rich in probiotics), which undoubtedly explains the enthusiasm it generates among consumers. The traditional nature of kefir lies in the use of fresh kefir grains as the sole ferment, passed down from producer to producer over generations. Kefir is a probiotic that is supposed to modify the intestinal microbiota and the metabolites produced. Recent studies have described positive health effects of kefir. These effects could be exerted by a combination of live microorganisms contained in the fermented beverage, as well as by the bioactive components released in foods as by-products of the fermentation process. Links between kefir and metabolic syndromes (insulin resistance, etc.) have also been described in animal models. Very few clinical studies have evaluated the effects of kefir in humans. Branched-chain amino acids (BCAAs) are provided by the diet and are essential to the human body. They are also markers of insulin resistance. Measuring metabolites such as BCAAs in biofluids would verify if kefir has an effect on food degradation and thus on the intake of essential amino acids. This information is important both to better understand the mechanism of action of kefir and its effects on the production of metabolites such as BCAAs.

Conditions

• Emotion
• Well-being

Interventions

Type	Name	Description
OTHER	Consumption of a control beverage, non-fermented carbonated drink	Consumption of a control beverage, non-fermented carbonated drink and measurement of the concentrations of metabolites such as BCAAs (valine, leucine, and isoleucine) in the biofluids (urine and saliva) of subjects, before and after regular consumption of fruit kefir.
OTHER	Consumption of fruit kefir	Consumption of fruit kefir and measurement of the concentrations of metabolites such as BCAAs (valine, leucine, and isoleucine) in the biofluids (urine and saliva) of subjects, before and after regular consumption of fruit kefir.
OTHER	Consumption of micro-filtered fruit kefir	Consumption of micro-filtered fruit kefir and measurement of the concentrations of metabolites such as BCAAs (valine, leucine, and isoleucine) in the biofluids (urine and saliva) of subjects, before and after regular consumption of fruit kefir.

Timeline

• Start date: 2024-06-04
• Primary completion: 2025-06-11
• Completion: 2027-06-11
• First posted: 2026-04-13
• Last updated: 2026-04-13

Locations

1 site across 1 country: France