Is Kombucha Good for Your Gut? Benefits, Risks, and Facts

Kombucha has surged in popularity among Americans and is known for its tangy flavor and possible health benefits. This fermented tea dates back to ancient times and appears to have originated in East Asia.

Advocates of kombucha promote it for its ability to enhance gut health and prevent chronic disease, but does the science back up these claims?

In this article, we’ll dive into kombucha’s history, potential benefits, how to consume it safely, and other gut health alternatives.

What is kombucha?

Kombucha is widely known as a functional fermented tea beverage. Kombucha is a lightly carbonated beverage with a slightly vinegary taste and tangy flavor.

Further, kombucha recipes typically use black or green tea, sugar, and other added flavoring agents like juice, spices, herbs, and scoby.

Scoby, or tea fungus, is a symbiotic culture of bacteria and yeast. It's made from tea and sugar through a fermentation process that lasts several days or weeks.

However, the specific type of bacteria and yeast culture created can vary depending on where and how it's made.

History of kombucha tea

Kombucha has been traditionally made for thousands of years. Current literature reports that it originated in East Asia in 220 BC for its theoretical "detoxifying properties." In 414 AD, a doctor named Kombu introduced it to Japan to help treat digestive issues.

Eventually, this fermented drink became popular in Russia and other European countries. In the 1960s, researchers in Switzerland stated that drinking kombucha was as beneficial as yogurt, increasing its popularity today.

Can kombucha support gut health?

While an increasing number of Americans are interested in drinking kombucha for its potential health benefits, is kombucha healthy, and can it help support gut health?

A 2019 systematic review reviewed the possible health benefits of kombucha, including:

• Antibacterial effects
• Altered liver, immune system, and digestive functions
• Detoxification
• Antioxidant and anti-tumor properties
• Chronic disease prevention (like diabetes, brain disease, and cardiovascular disease control)

While results from some of these studies suggest possible health benefits of kombucha, these claims were found mainly in non-human studies.

Findings gathered from animal studies can not be directly adapted to humans, as our bodies function differently. Thus, more research from human studies is needed to determine whether these claims apply to humans.

Currently, no official U.S. government agencies recommend using kombucha to support specific gut health issues.

However, theoretically, certain brands of kombucha may have probiotic properties depending on their fermentation process and, specifically, the types and amounts of bacteria used.

Further, polyphenols (a type of antioxidant) found in tea may help to support the growth of certain types of bacteria in the gut, which could help promote overall gut health.

Who should exercise caution with kombucha?

According to the Centers for Disease Control (CDC), 100 grams, roughly 4 ounces, of kombucha daily is considered safe for the average healthy adult.

However, specific populations may be at higher risk of adverse health effects and should avoid drinking kombucha or discuss with their doctor before consumption:

• Pregnant individuals
• Those with mold allergies
• Immunosuppressed individuals (like transplant patients and those with HIV or certain autoimmune conditions)
• Individuals susceptible to acidosis
• Those with alcohol sensitivities
• Children (due to low levels of alcohol content)

Since kombucha is only considered safe at 4 ounces per serving, drinking too much kombucha may lead to adverse health effects.

Choosing the right kombucha

Although drinking kombucha currently lacks evidence for specific gut health benefits, it may help healthy gut maintenance in general. Further, it is relatively safe for the average healthy adult.

However, one primary consideration when choosing a kombucha is sugar concentration.

The amount of sugar in commercially available kombucha can vary, but typically, kombucha contains anywhere from 3–25+ grams of sugar per 8 oz serving.

So, what amount of sugar should you aim for when choosing kombucha? The recommended sugar intake overall varies based on age, sex, health status, and activity level, to name a few.

However, the Dietary Guidelines for Americans 2020–2025 recommends no more than 10% of calories come from added sugar daily for those two years of age or older. Further, the American Heart Association recommends no more than 9 teaspoons (36 grams) of added sugar daily for adult men and no more than 6 teaspoons (25 grams) daily for women.

Choosing a kombucha low in added sugar may help you meet the recommended guidelines. Lower-sugar options generally contain 5% or less of calories from added sugar per serving.

Making your own fermented tea at home

No official U.S. government website provides safe handling practices for brewing your own kombucha tea at home. However, the Department of Agriculture and Markets in New York offers manufacturing practices for brewing and distributing kombucha on a commercial level.

If you choose to brew your own kombucha, you can follow commercial guidelines for food safety but know there are risks.

That being said, here is the general process for brewing kombucha.

Step 1: Choose a kombucha recipe. You'll need black or green tea, sugar, SCOBY, and other flavoring agents such as herbs, extracts, or juice.

Step 2: Fermenting process.

a. Use hot water (165ºF/ 74ºC) to steep your tea with sugar for about ten minutes.

b. Allow your tea mixture to cool to room temperature and add your SCOBY.

c. Cover your kombucha and let it ferment for 7–21 days at room temperature. Test the pH several times throughout the fermentation process. The pH should remain between 2.5 to 4.2. If at any point your kombucha shows signs of mold, discard it. The fermentation process is typically considered done when the product reaches a pH of 4.2

d. Add in any remaining ingredients, like flavoring agents.

Step 3: Store your homemade kombucha in the fridge in an airtight bottle for 1–3 months. Enjoy!

If you do not wish to brew your own, store-bought kombucha is an option.

Risks and interactions to consider

Food safety practices are essential when making kombucha, as you are working with bacteria cultures and thus have an increased risk of a foodborne illness.

Here are some tips for reducing your risk of illness when making kombucha tea:

1. Practice good hand hygiene.
2. Choose the right SCOBY. Purchase a SCOBY from a reputable company/retailer. Avoid SCOBY that contains visible mold, appears discolored, or has a strong smell.
3. Avoid a long fermentation process. Long fermentation leads to a more acidic environment where certain harmful bacteria and yeasts thrive.
4. Use a food-safe antifungal preservative. A 0.1% concentration at a pH equal to or less than 4.2 of potassium sorbate or sodium benzoate can be added to help avoid contamination.

Alternatives to kombucha for gut health

The current evidence on kombucha and gut health benefits is lacking. Thus, if you want to improve your gut health, here are some science-backed alternatives to kombucha that may help.

Probiotics

According to the International Scientific Association for Probiotics and Prebiotics (ISAPP), probiotics are defined as live microorganisms that provide a specific health benefit when taken in specific doses.

Probiotics can come in many forms, such as:

• Some fermented foods (like some yogurts and kefirs)
• Liquids
• Capsules
• Powders

Fermented foods are made with microorganisms; however, fermented foods don't always contain live microorganisms in their end product (e.g., sourdough bread) or may not contain enough live microorganisms to provide health benefits. Thus, not all fermented foods are considered probiotics.

While fermented foods like kombucha may help support the gut, the evidence in this area is limited.

Conversely, certain probiotics have been widely studied for their potential gut health benefits. Currently, several probiotics on the market have scientific evidence supporting their use for specific gut health conditions.

Further, probiotics are one possible line of management for certain gut health issues. Your doctor may suggest probiotics to reduce certain digestive health issues or provide other options instead of or alongside probiotics, depending on your specific needs.

Talk to your healthcare provider to see what, if any, probiotics are right for you and your gut health needs.

Prebiotics

Prebiotics are a type of non-digestible dietary fiber that acts as food for the ‘good’ bacteria in our guts.

The evidence on prebiotics and their many health benefits is substantial. Notably, here are some of the more prominent benefits of prebiotics:

Prebiotics can be found in supplement form but are primarily found in foods. Some examples of foods that contain prebiotics are:

• Bananas
• Onion
• Garlic
• Asparagus
• Apples
• Avocado
• Oats

The average American does not meet their daily fiber needs, with an average intake of around 16 grams of fiber daily. The Dietary Guidelines for Americans recommend that adult men consume 38 grams daily and adult women consume 25 grams daily.

Eating a varied diet

Research indicates that a varied diet consisting primarily of whole foods is crucial for maintaining good gut health by increasing the population and types of ‘good’ bacteria in the gut.

An unbalanced gut may be linked to digestive health diseases like irritable bowel disease.

Incorporating movement

Current evidence suggests that increasing physical activity (even walking counts!) may increase the number of ‘good’ bacteria in our gut. More beneficial bacteria help to reduce the risk of gut health issues like inflammation.

Managing stress

Both short and long-term stress can negatively impact our gut. Specifically, stress releases hormones like cortisol that can quickly change the composition of our gut bacteria, causing harmful bacteria to overcrowd the beneficial bacteria.

Reducing our ‘good’ bacteria puts you at greater risk of developing chronic diseases.

Some strategies for managing stress include:

• Meditation
• Gentle yoga
• Going for walks
• Deep breathing
• Limiting electronics

Conclusion

Drinking kombucha likely isn't harmful to the average adult in small quantities. However, while it may have properties that may support gut health, its effectiveness is not clear due to lacking scientific evidence.

Overall, consuming a healthy diet rich in fiber and probiotic foods, as well as implementing positive lifestyle changes, will likely have a positive impact on your gut health.