Kombucha

Context : A recent human study published in The Journal of Nutrition explored the effects of kombucha, a fermented tea drink, on gut microbiota, especially in people with obesity.

Study Highlights:

• Participants: 46 healthy adults in Brazil (23 with obesity, 23 with normal weight).

• Intervention: Daily intake of 200 ml of lab-prepared kombucha for 8 weeks.

• Findings:

  • Overall microbial diversity remained largely unchanged.

  • Key beneficial bacterial shifts in the obese group:

    • ↑ Akkermansiaceae (linked to improved blood sugar control).

    • ↑ Prevotellaceae (associated with better insulin sensitivity).

    • ↓ Ruminococcus and Dorea (linked to inflammation and obesity).

  • In normal-weight individuals:

    • ↑ Parabacteroides (linked to reduced inflammation).

  • ↓ in fungi like Exophiala and Rhodotorula (linked to cystic fibrosis and obesity).

• Kombucha Composition:

  • Rich in polyphenols (flavonoids and phenolic acids) which feed beneficial gut microbes in the colon.

• Metabolic markers (blood glucose, insulin, inflammation) did not significantly improve, indicating modest effects.

• Results are not generalisable:

  • Microbiomes differ by diet, genetics, region, and health.

  • Indian guts, especially from plant-based diets, already have high Prevotella levels.

  • Variations exist within India — e.g., North Indians vs. South Indians, urban vs. tribal populations.

• Kombucha may help rebalance the gut microbiome, especially in obese individuals.

• Effects are modest and require more long-term, large-scale studies.

• No single kombucha product can be universally beneficial — gut health effects are context-specific, influenced by geography and lifestyle.