Apple Cider Vinegar for the Gut – Can It Affect the Gut Microbiome?

Have you heard that apple cider vinegar may be good for the stomach or gut microbiome? Apple cider vinegar contains acetic acid, among other compounds, and has been studied for several possible effects in the body.

Research on vinegar has shown possible effects on blood sugar after a meal, while knowledge about how apple cider vinegar affects the gut microbiome, SIBO and other gastrointestinal symptoms is much more limited.

In this article, we look at what is actually known about apple cider vinegar, the stomach and the gut microbiome – and what you should consider if you want to try it.

Is apple cider vinegar good for the stomach?

There are several theories about how apple cider vinegar may affect digestion, but it is important to distinguish between what has been studied and what remains a hypothesis.

Acetic acid, which is found in vinegar, has been studied for its effects on:

• Blood sugar and insulin after a meal
• Gastric emptying
• Feelings of fullness
• The breakdown and absorption of carbohydrates

Studies and reviews show that vinegar may reduce the rise in blood sugar and insulin after certain meals. However, the effect varies between studies, and it cannot be concluded that apple cider vinegar itself improves digestion in general.

Can apple cider vinegar affect blood sugar?

There is relatively more research on vinegar and blood sugar than on vinegar and the gut microbiome.

A systematic review and meta-analysis of clinical studies found that vinegar consumed with a meal could reduce post-meal blood sugar and insulin responses.

A newer review from 2026, which brought together several meta-analyses of randomized controlled trials, also found improvements in some measures of blood sugar. At the same time, the certainty of the evidence varied between different outcomes.

This does not mean that apple cider vinegar replaces treatment for diabetes or other metabolic conditions. If you have diabetes and take medication, you should talk to your healthcare provider before making major changes.

Can apple cider vinegar help digestion?

Some research suggests that acetic acid may affect gastric emptying and how the body handles carbohydrates after a meal.

It is less certain whether this means that apple cider vinegar improves digestion in general.

The claim that apple cider vinegar automatically increases stomach acid production and therefore improves digestion should therefore not be presented as an established fact.

Can apple cider vinegar affect the gut microbiome?

This is an interesting question, but research in this area is still limited.

Vinegar contains acetic acid and other compounds that may affect microorganisms. Laboratory studies show that acetic acid has antimicrobial properties, but this does not automatically mean that apple cider vinegar changes the human gut microbiome in a specific or predictable way.

A small human study in which apple cider vinegar was included as part of a diet with a higher content of short-chain fatty acids found changes in, among other things, fecal short-chain fatty acids. However, the study investigated a combined dietary intervention and therefore cannot show that apple cider vinegar alone changes the gut microbiome.

There is therefore a biological basis for being interested in the connection, but more human research is needed before we can say that apple cider vinegar balances the gut microbiome.

Can apple cider vinegar help with SIBO or SIFO?

It is not yet possible to draw firm conclusions that apple cider vinegar treats SIBO or SIFO.

SIBO stands for Small Intestinal Bacterial Overgrowth and refers to an increased amount of bacteria in the small intestine.

SIFO stands for Small Intestinal Fungal Overgrowth and is used to describe an overgrowth of fungi in the small intestine.

Apple cider vinegar has sometimes been suggested as a way of affecting the microbial environment in the gastrointestinal tract, partly because of the antimicrobial properties of acetic acid.

However, an effect against microorganisms in a laboratory setting is not the same as apple cider vinegar treating SIBO or SIFO in humans.

Apple cider vinegar should therefore not be considered a treatment for SIBO or SIFO.

If you experience recurring bloating, gas, diarrhea, constipation or other gastrointestinal symptoms, there may be several possible causes. A medical assessment can help determine whether further investigation is needed.

Can apple cider vinegar help with bloating?

Current knowledge is still too limited to say that apple cider vinegar generally reduces bloating.

If you notice that your stomach feels better or worse after drinking it, your individual response may play a role.

It is also important to remember that vinegar is acidic, and some people may experience stomach discomfort or nausea after drinking it. In a human study, the increased feeling of fullness after consuming vinegar was partly associated with poorer tolerance and more nausea.

Apple cider vinegar is therefore not necessarily the best choice for a sensitive stomach.

Can apple cider vinegar help with weight loss?

Apple cider vinegar has been marketed as a way to increase feelings of fullness and support weight loss.

There is some research on vinegar and body weight, but the results are not sufficient to consider apple cider vinegar a weight-loss method. A newer review from 2026 found a small average reduction in body weight in the combined data, but the effects varied between different outcomes and studies.

Another study also found that the increased feeling of fullness after consuming vinegar could be associated with nausea and poorer tolerance.

Apple cider vinegar should therefore not be used as a shortcut for weight loss.

How much apple cider vinegar can you drink?

If you want to try apple cider vinegar, it is wise to start carefully.

One simple approach is to:

• Start with 1 teaspoon (5 ml).
• Dilute it in a glass of water.
• Observe how your stomach reacts.
• Avoid drinking concentrated vinegar directly.

There is no established dose that is right for everyone, and more is not automatically better.

If you take medication, have a medical condition or are unsure whether apple cider vinegar is suitable for you, talk to your healthcare provider before using it regularly. Supplements and other complementary products can interact with medications.

When should you be careful with apple cider vinegar?

Apple cider vinegar is an acidic product and is not suitable for everyone.

Be particularly cautious if you:

• Experience stomach pain or nausea from it.
• Have a sensitive stomach or reflux symptoms.
• Take medication that may be affected by changes in diet or blood sugar.
• Have a condition where you need to monitor your blood sugar.
• Plan to use larger amounts regularly.

Natural does not automatically mean risk-free. How a product is tolerated can vary from person to person.

Is apple cider vinegar right for you?

It depends on why you want to use it.