What is kombucha? 6 scientific benefits

Kombucha is a fermented tea drink with an acidic flavour and slight fizz, which is increasingly popular among the health-conscious.

As kombucha has a low calorie and sugar content, it’s an excellent choice for consumers looking for an alternative to water, without any bad-for-you ingredients.¹

In this article, we’ll explain what kombucha is, why it’s so popular, and investigate the health hype surrounding it.

Then, we’ll hear what side effects kombucha has, and who might want to avoid this fermented beverage.

The popularity of this fizzy, fermented tea is showing no signs of slowing down. There are many pre-bottled alternatives on the market, but have you considered brewing your own?

But first, let’s talk briefly about the benefits of kombucha and why we’re seeing this fermented fizz everywhere from health food shops to the mixer shelves in hipster bars.

In this article, you’ll find out

• What kombucha is
• Benefits of kombucha
• How to make kombucha
• Kombucha side effects
• What hard kombucha is
• Hard kombucha benefits
• Kombucha vs. hard kombucha
• Kombucha FAQs

What is kombucha?

Kombucha is made from tea fermented with sugar and a bacterial culture called a SCOBY (symbiotic colony of bacteria and yeast).

The fermentation process takes between 7 to 14 days.

Both green and black teas are used to produce kombucha. Homebrewers typically prefer to use black tea, as it ferments faster.

Black tea varieties typically have a deeper flavour. In contrast, green tea kombucha has a more delicate flavour and an almost grassy quality that some drinkers love.

What does kombucha taste like?

Kombucha is a mildly fizzy, fermented cold tea drink with a slightly sour flavour. It’s made from sweetened tea and a live culture known as a kombucha SCOBY (short for symbiotic culture of bacteria and yeast.) 

The origins of the drink are estimated to go back as far as 2000 years.²

Also, kombucha can be made in a range of flavours, from refreshing raspberry to ginger and lemon.

But the soar in popularity in recent years in the UK is likely to be down to rising interest in the role of fermented foods in gut health.

This has led to pre-bottled versions of this ancient brew becoming more widely available.

Why is kombucha popular?

Fermented drinks have grown in popularity over the past decade as emerging science highlights the benefits of probiotics.³

The world consumed over 18 kilotonnes of probiotics in 2018!⁴

Kombucha has likely benefited from its association with the probiotic food trend.

This fermented tea has become increasingly fashionable in the United Kingdom, so much so that an estimated 1,000 British pubs sell kombucha to health-conscious consumers.⁵

What is kombucha good for? 6 benefits

Kombucha has been linked to a whole host of health benefits. This is how kombucha can support you in your healthy lifestyle:

1. Source of probiotics

Thanks to its bacteria content, Kombucha tea may help to maintain a healthy population of microorganisms in your gut.

This could have benefits for your digestive health and overall wellness.⁶

Fermented foods are made from bacterial cultures which produce probiotics during the fermentation process, and kombucha is no exception. Although probiotic content is linked to better health outcomes, no current evidence proves kombucha provides effective probiotics for health.^7,8

2. Antioxidant content

Both green and black tea contains antioxidants called polyphenols, which have been linked to cardiovascular health.⁹

Although studies show kombucha’s fermentation process enhances tea’s antioxidant properties, there’s no conclusive evidence which proves kombucha’s polyphenol content positively impacts health.¹⁰

3. Vitamin and mineral content

Kombucha contains essential minerals, including zinc, copper, magnesium, iron, nickel, and cobalt. Vitamins B1, B6, B12 and Vitamin C are also present.¹¹

4. It’s a great alternative to less healthy beverages

In today’s more health-conscious age, people are choosing kombucha instead of sugary, high calorie carbonated drinks or alcohol.

5. May help you lose weight

Kombucha may offer some of the same weight loss benefits as green tea, all thanks to its polyphenol content.

While the polyphenols in kombucha specifically require more research, scientists in 2010 found that foods and drinks with polyphenols in them may facilitate weight loss and even prevent weight gain going forward.¹²

6. May have antibacterial properties

Kombucha made from green tea, in particular, has been shown to possess microbial properties.

Specifically, it was found to inhibit Staphylococcus epidermidis, Listeria monocytogenes and Micrococcus luteus.

Not only this, but it may also have anti-Candida potential, against infection causing bacteria and Candida yeasts.¹³

How to make kombucha

Are you ready to test the benefits of kombucha? Do you fancy a mini microbiology project of your own?

Following a simple 7 step process, you can ferment your own fizzy tea drink brimming with healthy bacteria.¹⁴

What is in kombucha?

Kombucha is usually made using 5 core ingredients. Here is what you’ll need to make 1 litre of the drink.

1. Cold water – 1 litre. Filter out chlorine first by boiling and allowing to cool
2. Tea ­– 1 bag (or loose tea equivalent) Black or green tea both work
3. Sugar – 50-100g Cane sugar is normally used, with the exact amount to suit your tastebuds
4. A kombucha SCOBY – 1 small A disk-shaped culture which creates the fizz during the fermentation process
5. A starter tea – 100ml This is kombucha reserved from a previous batch to kickstart your new brew. Your SCOBY should come sitting in this liquid.

What else you’ll need

• A large, glass jar (clear so you can see what’s happening.)

Are there side effects of drinking kombucha?

Some unpleasant side effects are sometimes associated with drinking too much kombucha.¹⁵

These include:

• Stomach pain
• Allergic reaction
• Nausea
• Dizziness
• Headache¹⁶

However, scientific studies show the majority of sufferers either had a pre-existing illness or drank a contaminated batch of kombucha.^17,18

Like with any live food or drink, it’s advised to allow your digestive system to adjust by building up the amount you drink gradually.

For example, start with 100ml a day for the first week and increase slowly. Also, it might not suit everyone.

Finally, if you’re pregnant, breastfeeding or have a compromised immune system, kombucha may not be suitable for you so ask your GP before introducing it into your diet.

Who should avoid kombucha?

People with gastric and kidney complaints are more likely to suffer an upset stomach from drinking kombucha than non-sufferers.¹⁹

Pregnant women may choose to avoid kombucha because of the alcohol content. However, it’s thought to be too low a concentration to affect a foetus.

Is hard kombucha good for you?

The gut-friendly potential of the traditional version of the drink is widely reported. This is down to the live cultures that can help to maintain a healthy population of bacteria in your gut.

This may aid digestion as well as supporting your immune health (but there’s limited research to support these claims).²¹

But what happens to the live microorganisms as the alcohol levels rise? There are questions and various opinions about whether the good bacteria can survive in a boozier environment.

There don’t seem to be any consistent answers, leaving any suggested gut-friendly benefits of high alcohol kombucha very much up for debate.

However, some of the other wellness perks of kombucha are more likely to withstand the extra fermentation.

For example, the beneficial acids remain in-tact, so the beverage retains some antioxidant capabilities.

And being gluten-free, it can be a less bloating alternative to beer, especially for those with an intolerance to wheat. Finally, it may have a lower sugar and calorie content than more sugary alcoholic drinks.

But all of this varies depends on the specific sugar and alcohol content of a specific brew.

In reality, any wellness boost offered by hard kombucha is likely to be fairly minimal. So, on balance, the boozy brew isn’t considered a health drink.

However, for some people, it can offer some benefits over other alcoholic beverages.

Can kombucha help you lose weight?

Since kombucha contains polyphenols, it may be able to help you lose weight.²²

One study from 2010 concluded that foods or drinks containing polyphenols may facilitate weight loss and prevent weight gain.²³

Should you drink kombucha every day?

While kombucha does have a few potential health benefits, that isn’t a green light for consuming too much of it.

The Centers for Diseases Control state that 115ml of kombucha, up to three times a day is safe to drink.²⁴  

The final say

Kombucha has multiple potential health benefits, due to it’s antioxidant contents and the nature of fermented foods.

But it’s worth noting that studies on the effects of kombucha are limited, so none of the benefits are 100% confirmed.

That being said, both shop-bought and homemade kombucha is a tasty drink to have – so why not give it a try?

Last updated: 15 February 2022