Kombucha

Kombucha is a fermented, effervescent tea drink made with sweetened black or green tea and a culture of bacteria and yeast.

Kombucha is a fermented, effervescent tea drink made with sweetened black or green tea and a culture of bacteria and yeast. It is often marketed as a health beverage, but evidence for health benefits is limited. The drink can contain small amounts of caffeine, alcohol, and acid depending on how it is made.

Overview

Kombucha is a fermented beverage made from tea, sugar, and a culture of bacteria and yeast. It is commonly sold as a refrigerated, lightly carbonated drink and may be flavoured with fruit, spices, or juice.

Production

To make kombucha, sweet tea is inoculated with a SCOBY (symbiotic culture of bacteria and yeast) and left to ferment for days or longer. During fermentation, microorganisms consume sugar and produce acids, carbon dioxide, and small amounts of alcohol.

Composition and nutrition

Finished kombucha can contain acids such as acetic and lactic acid, trace vitamins, sugar, caffeine, and ethanol. The exact composition varies widely by recipe, fermentation time, and whether the product is homemade or commercially produced. The drink typically has a sweet-sour, tangy, or vinegary flavour.

Health claims and safety

Kombucha is often promoted as beneficial for digestion or general wellness, but medical reviews say there is not enough proof for many of these claims. Reported risks include stomach upset, allergic reactions, infections, and contamination concerns in poorly made batches. Major medical sources indicate that evidence for health benefits is limited and not well proven.

Pregnancy and special populations

Because kombucha may contain alcohol, caffeine, and live microorganisms, some medical sources advise pregnant and breastfeeding people, as well as immunocompromised people, to avoid it. Safety depends on product quality and exact alcohol content, which can vary.