Characteristics and Risks of Kombucha Tea

Kombucha tea is a drink made from tea that has been fermented by a colony of bacteria and fungi. Many properties are attributed to it, but it's important to know the side effects it can have.
Characteristics and Risks of Kombucha Tea
Sergio Alonso Castrillejo

Reviewed and approved by the pharmacist Sergio Alonso Castrillejo.

Written by Editorial Team

Last update: 07 October, 2022

Kombucha tea is becoming more and more popular around the world because of its many health benefits. The microorganisms in charge of fermenting the sugary tea to produce this drink are called “kombucha mushroom”. Despite its multiple benefits, however, you should also know the risks of Kombucha tea.

At the start of the fermentation process, different types of microbes participate. However, with time, only those that make up the gelatinous body characteristic of the Kombucha survive. The rest die due to the high degree of acidity and the antibiotic substances secreted into the tea.

The flavor of Kombucha tea depends on the fermentation time. Therefore, it’s softer and sweeter if it ferments less time and gradually acquires a more intense and acidic flavor.

Nutritional characteristics

A large jar and pitcher of kombucha tea next to each other.
The flavor of Kombucha tea depends on the fermentation time, being smoother the less time you leave it.

Kombucha tea boasts the following nutritional benefits:

  • It’s rich in vitamins and minerals necessary for important biochemical processes that take place in our bodies. These include vitamin B and C, iron, zinc, copper, and manganese.
  • It boasts a variable amount of antioxidants from the black tea people use to make Kombucha tea. Their presence depends on the fermentation time.
  • It has a high amount of microorganisms which gives it a powerful probiotic effect.

The Benefits of Kombucha tea

The lack of studies regarding this drink means we can’t confirm that the benefits traditionally attributed to it are true. However, the antioxidants and micro-organisms present in it may be related to an improvement in digestive functions.

People also claim it has beneficial properties for cardiovascular health, liver functions, and stress.

Also, we have to remember that this drink is made from tea, generally green or black. Therefore it will also have those benefits, such as:

  • Helping with concentration problems.
  • A diuretic effect.
  • Purifying action.
  • Stimulating effect.
  • Astringent properties.

You might be interested in: How To Make Kimchi: The Healthiest Fermented Food

Kombucha Tea Side Effects

Contamination risk

Woman on couch holding stomach in pain.
One of the risks of Kombucha tea is contamination by microorganisms from the fermentation process.

The greatest risks of Kombucha tea are related to the contagion with microorganisms if you don’t make it following a series of specific hygienic measures.

During fermentation, Kombucha tea can be exposed to numerous bacteria and yeast that are harmful to your health. If you don’t let it ferment long enough, the drink won’t get enough acidity and alcohol to eliminate these microorganisms.

Samples contaminated by Aspergillus mold, which produces liver-damaging toxins, are frequently detected, as well as contamination by bacteria of the genus Helicobacter pylori or Salmonella. Therefore, we don’t recommend this drink for people who suffer from any intestinal or liver condition.
Nor do we recommend consuming it for immunosuppressed people or those who have deficiencies in the functioning of the immune system. Pregnant women, lactating women, children under the age of 5, patients with HIV, or any infection should refrain from drinking Kombucha.

Excessive Kombucha tea consumption

Even if you don’t belong to any of the previous groups, you should drink it in moderation, since in excess it can cause digestive upset.

We should also note that it’s a drink with a high content of alcohol and sugar. Therefore you should monitor the rest of your diet to make sure that you don’t exceed the maximum recommended levels for those substances.

Industrial Kombucha tea

You can also buy industrially manufactured Kombucha tea. In this case, they sterilize the drink, but it loses its probiotic effect, resulting in a drink with little nutritional value.

In summary, this drink can be beneficial in moderation. However, drinking it doesn’t guarantee any short or long-term benefits beyond those that the tea itself causes. In fact, some think that drinking just black or green tea is healthier. This is because it doesn’t have alcohol or microorganisms that can upset your stomach.

Keep this in mind when drinking kombucha in the future.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


  • Qadir MI., Role of green tea flavonoids and other related contents in cancer prevention . Crit Rev Eukaryot Gene Expr, 2017. 27 (2): 163-171.
  • Srinivasan R., Smolinske S., Greenbaum D., Probable gastrointestinal toxicity of kombucha tea. Journal of General Internal Medicine, 2002.
  • Plaza Díaz J., Ruiz Ojeda FJ., Vilchez Padial LM., Gil A., Nutrients, 2017.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.