Google the word Kombucha health drink and you’ll get thousands of search results. Everybody is talking about it, but is it a health drink, glorified cordial…or a Candida soup? 

Let’s check the facts, so you can work out if you still want to drink it.

Fact – Kombucha is All The Rage Right Now

With all those Google hits, it was absolutely no surprise that my question to the Facebook community last week: “do you drink Kombucha, and why or why not?”, got heaps of responses.

Kombucha Health Drink | Downsize Me

Most people loved it, some hated it, and some couldn’t be bothered to make it. Several couldn’t tolerate it for health reasons (more on this later).

A handful of people had no idea what we were talking about (trust me, ignorance is bliss).

It’s interesting that so many people believe kombucha has health benefits including better immunity, better gut health and more energy. Some people said they felt noticeably better when they drink it. One of my clients even phoned me to say her friend’s Oncologist has recommended it, and to ask, should she buy it?

I’m a scientist and a truth-seeker. So I researched the facts. Here they are.

What is Kombucha?

Kombucha is, simply, fermented tea.

You mix some green or black tea with sugar, let it cool, and add a culture (SCOBY – symbiotic culture of bacteria and yeast) that ferments the sugar in the tea. 

The SCOBY (‘mother’) floats around in the tea mixture, using up the sugars, and after 3 – 7 days you have a fizzy drink that can be decanted and flavoured with berries, turmeric, or other things.

Kombucha Health Drink | Downsize Me

If you leave it fermenting too long and it becomes sharp and vinegary (acidic). 

Read This Before You Drink Or Make Kombucha

Kombucha sounds like a fun, weird science experiment. Better than fizzy drinks and cheap to make, right?

Not so fast. My primary aim is to help you eat right for your unique body type, so I did the research for you. Based on people’s comments last week, I put together a Q and A and then looked for some scientific data to answer them. 

You might want to read this before you decide to launch into kombucha-land.

Note: Most of the detailed info comes from an in-depth 2016 study – there’s limited, comprehensive data published right now about the composition and nutritional value of kombucha.

Q – What are the yeast and bacteria in the SCOBY?

This 2016 paper (Chakravorty, et. al) has the most in-depth information I could find about the yeast and bacteria. It shows how the culture changes over 21 days of fermenting (with data collected at days 0, 7, 14 and 21).

Since most people drink kombucha after 3 – 7 days of fermenting (it becomes way too vinegary after that), I’m just showing the most relevant data from Day 7 of the study (unfortunately no data for day 3!).

At Day 7 in the fermentation process:

  • The SCOBY was 73 – 83% Candida sp. (yes, I said Candida – park that for later)
  • The liquid was 78% Lachancea sp. (another yeast), 16% Candida sp
  • The liquid also contains the acid-producing bacteria Komagateibacter which makes the brew acidic (pH 2.73 – like stomach acid)

Note: other brews are reported to be rich in the yeast Zygosaccharomyces sp.

So regardless of the brew, yes, it’s rich in yeasts of some description. 

Q – How does the fermentation process work?

Here’s a simple summary of the fermentation process in kombucha.

Kombucha Fermentation Process | Downsize Me

Q – Is there sugar in kombucha? Is there alcohol in kombucha? Caffeine?

The exactly amounts left after 3 – 7 days depends on the microbes in the SCOBY. 

Using the Chakravorty study as a guide for what happens at day 0 and 7 of fermentation:

  • the sugar content increases slightly
  • alcohol is virtually nil, and
  • caffeine degrades a little.

Here is the data from Days 0 and 7 of the Chakravorty study, showing ‘standard’ equivalent intakes for Day 7.

  Day 0 Day 7 Day 7 – what happens, what it equates to
Ethanol (alcohol)  0.046 g/L 0.28 g/L

Increases during fermentation

Equates to 0.02% of a standard drink (which contains 10g pure alcohol)

Classed as ‘non-alcoholic’

Sugar (Day 0),           Reducing sugar* (Day 7)

6.8 g/L 8.2 g/L 

Increases during fermentation due to creation of simple sugar byproducts 

Equates to 2 teaspoons sugar

World Health Organisation recommends up to 6 tsp (24g) added sugar/day

Caffeine 1.06 g/L 0.948 g/L

Degrades during fermentation 

Equates to 1 cup coffee or 2 cups tea 

Represents a typical daily intake


Q – “Kombucha health drink” – is it? What are the nutritional benefits?

Kombucha fans rave about the health benefits. Here are what the research shows:

One of the main health benefits of drinking kombucha is the formation of a molecule called DSL in the fermentation process. This molecule is believed to lower cholesterol, promote detoxification in the liver and protect the liver

Generally, fermented foods are considered to be excellent for gut health, based on the microbes they contain. Following on from that, a healthy gut means a healthy immune system. Be aware that fermented foods differ in the cultures they contain.

  • Kombucha cultures tends to be dominated by yeasts, including Candida sp.,
  • Yoghurt, kimchi, sourdough and sauerkraut cultures are dominated the bacteria Lactobacillus sp. 
  • Tempeh fermentation involves the fungus Rhizopus sp. 

Several studies report that vitamin B1, B2, B6 and B12 are produced during fermentation (cited in this reference)

Health-giving polyphenols are also found in kombucha – the exact same ones you find in regular (unfermented) green or black teas. Chakravorty’s study showed that the amount of polyphenols in kombucha increased with changes in the bacterial colony. 

Kombucha Health Benefits | Downsize Me

The Kombucha Health Drink – Is It Right For You?

For most people, kombucha is probably ok, even beneficial….but maybe not for people with gut issues, yeast sensitivity, and/or anxiety issues (these three are often related).

1. Maybe not, if you have gut issues

If you have an issue like a bacterial overgrowth (SIBO) will probably get sick from eating fermented foods. So, if you react badly to fermented foods, it’s probably worth getting your gut checked. Dr Rhona Creegan is a good place to start.

2. Maybe not, if you are sensitive or intolerant to yeast

Kombucha is high in yeastwhereas other fermented foods are rich in probiotic bacteria.Some experts say to avoid kombucha if you’re prone to yeast infections, although others disagree (be prepared to do a full gut fixing protocol, in that case).

3. Not if you have an issue with histamine

If you’re like me, and have a genetic predisposition to histamine issues, then you should probably stay away from fermented foods and start working on gut health through other means to rectify the situation (see point 1).

I’ve been experimenting with kombucha, and most of the time I get the typical histamine reactions – reflux, anxiety, itchy eyes, bloating and sneezing.

4. Not if you’re highly anxious and/or sensitive to caffeine

Aside from histamine-related anxiety, some people are super-sensitive to caffeine, and can’t even tolerate one coffee per day without feeling jittery and anxious. 

If this is you, it’s probably best to stay away from kombucha, or try to find one of the rare kombucha brews that’s caffeine-free.

5. Yes, if you’re generally healthy, don’t have issues 1 – 4 above, and want to boost your gut and liver health.

Give it a whirl if you like the look of it and are symptom-free!

So, should you bother with kombucha?

If you have any gut or intolerance issues, you can simply drink regular old tea, or get your nutrients another way. Try some and see how it sits with you over the following 2 – 3 hours (that’s the golden rule for ANY food or drink).

If you’re healthy and well, without any issues, then sure, drink it.

Generally, I think one person in last week’s Facebook discussion said it best:

Once you’re healthy, does taking/drinking/consuming more uber healthy stuff make you any more healthy? I eat what I like and drink what I like. I am already healthy.

She nailed it for me.

You can jump on the super-food bandwagon if you like and enjoy the health benefits of kombucha. But maybe, kombucha is just another thing you will end up feeling you ‘should’ be doing.

Maybe trying to drink enough water and eat enough green vegetables is enough – and an easier place to start.

Melanie White

Melanie White

Chief Inspiration Coach

I'm a quirky scientist and a Health and Wellness Coach who helps 35+ women to understand and eat right for their body type.