Kombucha tea is a slightly sweet, slightly acidic beverage.

It’s increasingly popular within the health community and has been consumed for thousands of years and promoted as a healing elixir.

Many studies have linked kombucha tea to many potential health benefits, including improved digestion, lower “bad” LDL cholesterol and better blood sugar management.

However, some people are concerned about its potential alcohol content.

This article examines whether kombucha contains alcohol.

Kombucha tea is a fermented beverage that is believed to have originated in China.

It’s produced by adding certain strains of bacteria, yeast and sugar to black or green tea. This mixture is left to sit for a few weeks at room temperature to ferment (1).

During fermentation, bacteria and yeast form a mushroom-like film on the surface of the tea. This film is called a living symbiotic colony of bacteria and yeast known as the SCOBY.

Fermentation gives kombucha tea its unique characteristics because it adds carbon dioxide, alcohol, acetic acid and other acidic compounds, as well as probiotic bacteria (2, 3).

Summary

Kombucha tea is a beverage made by fermenting black or green tea with certain strains of bacteria, yeast and sugar.

Fermentation involves the breakdown of sugar into alcohol and carbon dioxide.

As a result, kombucha tea does contain small amounts of alcohol.

Commercial kombucha teas are labeled “non-alcoholic” because they contain less than 0.5% alcohol. This meets regulations set by the US Alcohol and Tobacco Tax Trade Bureau (4).

However, homebrewed kombucha teas tend to have significantly higher alcohol content. In fact, some homebrews have as much as 3% alcohol or higher (2, 5).

The alcohol content of commercial kombucha teas shouldn’t concern most people.

However, pregnant or breastfeeding women should avoid drinking homebrewed kombucha tea as it may contain significantly higher amounts of alcohol.

Federal agencies recommend avoiding alcohol throughout pregnancy. What’s more, homebrewed kombucha tea is unpasteurized and may raise the chances of miscarriage (6).

Breastfeeding mothers may want to avoid homebrewed kombucha as well, as alcohol can pass through breast milk.

Summary

Commercial kombucha teas contain less than 0.5% alcohol, while homebrewed kombucha teas may have significantly higher amounts.

Aside from its alcohol content, kombucha tea has other properties that may pose certain risks.

Here are some common concerns about kombucha teas.

Some Varieties Are Unpasteurized

Pasteurization is a process in which high heat is applied to liquids or foods.

This process is designed to kill harmful bacteria and has significantly lowered the risk of tuberculosis, diphtheria, listeriosis and many others diseases (7).

Some types of kombucha teas — especially homebrewed varieties — are unpasteurized and may host potentially harmful bacteria.

People with weakened immune systems, older adults, children and pregnant women should avoid homebrewed kombucha tea because it may cause serious harm if it carries harmful bacteria (7).

Contains Caffeine

Kombucha tea is made by fermenting green or black tea, which naturally contain caffeine.

While caffeine has health benefits, some people choose to avoid it because of its side effects such as restlessness, anxiety, poor sleep and headaches (8, 9).

If you refrain from caffeine, kombucha tea may not be right for you.

May Cause Headaches or Migraines

Fermented foods and beverages, such as kombucha, can be high in tyramine, a naturally occurring amino acid (10).

Though it’s unclear why it happens, several studies have linked tyramine intake to headaches and migraines in some people (11, 12).

If drinking kombucha tea gives you headaches or migraines, consider abstaining.

Homebrewed Varieties May Be Dangerous

Homebrewed kombucha teas are considered riskier than store-bought alternatives.

That’s because homebrewed kombucha has a higher likelihood of contamination, which may cause serious health problems and even death (5, 13, 14).

Keep in mind that homebrewed varieties may contain upwards of 3% alcohol (2, 5).

If you make kombucha tea at home, be sure to prepare it properly. If you worry about contamination, it’s best to drink store-bought options.

Summary

Kombucha tea contains caffeine, may be unpasteurized and could cause headaches or migraines. Because of the potential for contamination, homebrewed varieties are potentially dangerous and even life-threatening.

While kombucha tea has its downsides, it’s also associated with health benefits.

Here are some potential health benefits of kombucha tea:

  • High in probiotics: Kombucha tea is a great source of probiotic bacteria, which have been linked to improved digestive health, weight loss and reduced feelings of depression and anxiety (15, 16, 17).
  • Manages blood sugar levels: Animal research demonstrates that kombucha may reduce the amount of sugar entering your bloodstream (18).
  • Lowers heart disease risk factors: Animal research shows that kombucha tea may lower “bad” LDL cholesterol and raise “good” HDL cholesterol. Additionally, it may protect LDL cholesterol against oxidation (18, 19, 20).
  • May lower the risk of certain cancers: Test-tube studies indicate that kombucha tea antioxidants may suppress the growth and spread of various types of cancer. However, human studies are unavailable (21, 22).
  • May support liver health: In one animal study, kombucha tea was more effective than black tea and enzyme-processed tea at protecting the liver against harmful substances, as well as treating damage (23).
Summary

Kombucha tea has been linked to several potential benefits. It’s rich in probiotics, may help manage blood sugar levels, improve some heart disease risk factors and potentially fight certain cancers.

Kombucha is a fermented beverage that is linked to many potential health benefits.

Commercial kombucha tea is labeled non-alcoholic, as it contains less than 0.5% alcohol.

Homebrewed versions may contain significantly higher amounts of alcohol and can pose several other health risks if improperly prepared.

For most, the alcohol in commercial kombucha teas should not be a concern.

However, people with alcohol addictions, as well as pregnant and breastfeeding women should avoid it.