• Alcohol contains acetaldehyde, and has been linked with the development of several gastrointestinal cancers including liver and colorectal cancer.
  • Irritable bowel syndrome: If consumed in moderation, alcohol does not generally affect IBS symptoms. Drinking a lot of alcohol or binge drinking does make IBS symptoms worse in majority of patients. If you are on a low FODMAP diet for IBS, there are specific kinds of alcohol you should avoid.
  • Inflammatory bowel disease: Alcohol consumption is likely to make IBD symptoms worse. It can also trigger IBD flares. Alcohol may clash with your IBD medications.
A glass of whisky
A glass of whisky

How alcohol affects the digestive system

Though some studies cite moderate amounts of wine as being beneficial for the heart, more recent meta-analyses suggest that there is no amount of alcohol that’s good for you.1 The study has been published in The Lancet as Alcohol use and burden for 195 countries and territories, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016. Its findings are not as dire as the headlines make out, but make it difficult to dispute that drinking is healthier than not.

Alcohol is one of the sources of a toxic molecule called acetaldehyde, which is a Group 1 carcinogen also found in cigarettes, polluted air and other types of fermented food. Acetaldehyde is naturally produced in our bodies in low levels, but consuming alcohol can dramatically increase its level, causing what can be irreparable damage and putting you at risk for a variety of cancers including esophagus, colorectal, and liver cancer.2

When you consume alcohol, the toxins it contains irritate your stomach, causing it to produce more acid. This can lead to heartburn, gastritis and ulcers. If you consume alcohol in large amounts, over time, it affects the secretion of enzymes that enable you to break down fat and carbohydrates. This can cause digestive problems and make it difficult for your gut to absorb the necessary nutrients from food.

That being said, for a healthy person, one or two drinks within the recommended alcohol intake shouldn’t cause any serious problems.3

Specific conditions

Depending on your particular diagnosis, the effects of alcohol consumption on your digestive health may vary. So let’s dive into the details to help you get a better understanding of the relationship between your gut condition and alcohol.

IBS and alcohol

As we have established, alcohol can affect the mucosal membranes that line the inside of your gut, and get in the way of effective nutrient absorption. You may wonder if these effects are amplified in IBS.4 Well, the effects of alcohol on IBS symptoms appear to depend on the type of IBS as well as the pattern of drinking.

Studies have found that binge drinking made gut symptoms worse in patients with IBS, but moderate or light drinking did not have much of an effect. One study found this effect more pronounced in female patients, as women who consumed over seven drinks a week were found to be more likely to have IBS.5 Similar conclusions were reached by another study by Ohlsson B,6 who found that high alcohol intake aggravates IBS symptoms, but moderate intake does not have the same effect.

Apart from that, the kind of IBS you have also plays a part. An observational study was done in 2013 looking at alcohol consumption and IBS. They found that the effects of alcohol are dependent on the drinking pattern (binge drinking affects IBS) and type of IBS. If your IBS symptoms mainly revolve around diarrhea (IBS-D), alcohol may affect your gut health more negatively and make your symptoms worse than if your main IBS symptom is constipation. Patients with constipation dominant IBS were less affected by alcohol.7

Finally, if you also have heartburn-like symptoms or dyspepsia, be wary of drinking too much alcohol as it has been clearly shown make heartburn much worse.8

Low FODMAP (Fermentable Oligo-, Di-, Mono-saccharides, and Polyols) alcohol

Many patients with IBS have found the low FODMAP diet helpful in reducing gut symptoms. This is a diet that starts off in a very restrictive manner, and to reap any potential benefits from it, you have to adhere to the plan strictly. This includes restrictions on certain types of alcohol.

Alcohol that contains low FODMAP can be preferable to other types that are more difficult to digest. Most types of wine are low FODMAP, as are gin, whisky and vodka (straight, not mixed with juices or tonic). Though most beer should be avoided if you are sensitive to gluten, it is otherwise low FODMAP.

Additionally, some people with IBS may find that their symptoms are less severe when they avoid gluten. Although a gluten-free diet hasn’t been proven to be overall effective in managing IBS symptoms, on the off chance that it works for you, we have an in-depth article on gluten-free alcohol.

Inflammatory bowel disease and alcohol

First of all, drinking enough fluids is essential if you have an IBD, especially if your symptoms are uncontrolled. It is important that you stay hydrated if you are be losing fluids from diarrhea. If you are avoiding alcohol for fear for dehydration, you may be relieved to know that the diuretic effects of alcohol, especially of low-alcohol, non-distilled drinks, is often overstated.9

Research findings

However, even though alcohol may not dehydrate you significantly, alcohol consumption isn’t generally recommended with IBD. A review was done in November 2018 looking at 12 studies investigating the link between IBD and alcohol.10 They concluded that alcohol use has bad effects on IBD symptoms, with majority of IBD patients complaining of worse symptoms after drinking alcohol.

Not only may alcohol worsen symptoms, it has also been identified as a possible trigger for a flare-up of IBD.11 Researchers have attributed this to it’s pro-oxidant properties and the harmful effects of alcohol on gut barrier function. Alcohol also weakens your immune system, and this is another way through which alcohol may trigger IBD flares.12 This study found that 75% of IBD patients experienced worse gut symptoms after consuming alcohol. But in contrast with IBS, the amount of alcohol consumed doesn’t really influence its effects on IBD symptoms.

It is often said that red wine is better than other forms of alcohol. To test this theory, another interesting study looked at moderate red wine consumption in IBD patients.13 They asked 21 patients with IBD to drink 1 to 3 glasses of red wine a day, for a week. They found that after one week, those with IBD had significantly increased intestinal permeability and concluded by stating “patients with inactive IBD who drink red wine daily may be at an increased long-term risk for disease relapse.”

Medications and alcohol

Apart from worsening the gut symptoms of your IBD, there are a few other considerations to take into account. Firstly, if you are on antibiotics or other medications to treat IBD, there is a good chance that alcohol may affect how these drugs work. Certain antibiotics, like metronidazole, can even give you a hangover effect if taken with alcohol. To be safe, check with your doctor to make sure that the medications you’re taking don’t clash with your alcohol consumption.

Common complications

High amounts of alcohol consumption has also been connected to liver disease, malnutrition, anaemia, and gastritis. These are all issues which are faced when living with IBD, independent of alcohol consumption. Drinking alcohol heavily while having inflammatory bowel disease will make it much more challenging to manage your gut condition.

Can alcohol reduce IBD risk?

You may have heard that the risk of developing ulcerative colitis is lowered with alcohol use. This controversial finding comes from a 1989 study by Boyko EJ et al. looking at coffee, alcohol, and ulcerative colitis.14 It is important to understand that this study investigated the chances of developing ulcerative colitis – alcohol was consumed before any participants were diagnosed. It does not look at the effects of alcohol when you already have IBD. Plus, the overall negative effects of alcohol on your gut health would offset any minimal protective effect alcohol may have for developing UC.

A newer prospective cohort study was done in 2017 looking at alcohol consumption and the risk of developing ulcerative colitis or Crohn’s disease. The results they found showed no connection between alcohol and developing IBD.15

Final thoughts

Like any other food product, alcohol, and its effects can be highly individualized. Your friend who has IBS may have no problem drinking a glass of sweet dessert wine, while you are seized with an acute attack of the bowels. If you have IBS, you may be able to continue drinking alcohol as long as you do not exceed the recommended amounts. On the other hand, with regards to IBD, it may just be best to avoid drinking alcohol.

But no one knows your body better than you do. Keep monitoring your symptoms, along with your food and alcohol intake to understand better how your gut reacts to alcohol.

  1. Bloomberg reports on recent research, “Although the study found that alcohol offered some protection against coronary-artery disease in women, “the strong association between alcohol consumption and the risk of cancer, injuries and infectious diseases” offset that.”
  2. Testino G. (2011). The burden of cancer attributable to alcohol consumption. Maedica6(4), 313-20.
  3. Though keep the conclusions of the aforementioned study in mind, “Alcohol use is a leading risk factor for global disease burden and causes substantial health loss. We found that the risk of all-cause mortality, and of cancers specifically, rises with increasing levels of consumption, and the level of consumption that minimizes health loss is zero. These results suggest that alcohol control policies might need to be revised worldwide, refocusing on efforts to lower overall population-level consumption.”
  4. Capili, B., Anastasi, J. K., & Chang, M. (2016). Addressing the Role of Food in Irritable Bowel Syndrome Symptom Management. The journal for nurse practitioners : JNP12(5), 324-329.
  5. Influence of alcohol consumption on IBS and dyspepsia.
  6. The role of smoking and alcohol behaviour in management of functional gastrointestinal disorders.
  7. Relationship between patterns of alcohol consumption and gastrointestinal symptoms among patients with irritable bowel syndrome.
  8. The role of smoking and alcohol behaviour in management of functional gastrointestinal disorders.
  9. Hydration status and the diuretic action of a small dose of alcohol, a study testing this question with beer.
  10. Alcohol and narcotics use in inflammatory bowel disease.
  11. The role of smoking and alcohol behaviour in the management of inflammatory bowel disease.
  12. The role of smoking and alcohol behaviour in the management of inflammatory bowel disease.
  13. Is moderate red wine consumption safe in inactive inflammatory bowel disease?
  14. Coffee and alcohol use and the risk of ulcerative colitis.
  15. No association of alcohol use and the risk of ulcerative colitis or Crohn’s disease: data from a European Prospective cohort study (EPIC).

Praveena Asokan


Praveena is a writer with a clinical medicine background After graduating with a medical degree MBChB from the University of Leicester (UK), she worked in various hospitals, including being a junior doctor for the gastroenterology department in NHH Wales, before working in medical research in Malaysia. This helped her transition to a career as a writer, and she now enjoys researching and writing on a number of health-related topics.