Mmmm…. coffee! Maybe you love the complex taste, nutty aroma, and the feel of a warm mug in your hands. Or perhaps it is the jolt of energy and boost of mental clarity that keeps you coming back.
Whatever it is, for many of us coffee is the first thing we reach for in the morning and what keeps us going all day long. No wonder it is one of the world’s most consumed beverages!
But what if you have IBS? Could your daily coffee habit be triggering your symptoms? Could it be the reason you run for the bathroom every morning or find yourself doubled over in pain?
Well, maybe. But before you give up your cup of joe make sure to read on to learn more about coffee and IBS. Discover who might benefit from reducing intake and why.
How Coffee Affects a Healthy Gut
There is not a lot of high-quality research on the effects of coffee in IBS. Much of what we know comes from our understanding of what coffee does to the gut of a healthy person.
Coffee reduces pressure on the lower esophageal sphincter – the valve between the stomach and esophagus. This can result in the reflux of stomach contents into the esophagus, commonly experienced as heart burn.
Coffee increases secretions in the stomach and small intestine (1). These include hormones that affect motility (or movement) of the gut. This also include gastric acid which is important in breaking down food.
The increase in gastric acid gives some people an uncomfortable feeling often described as indigestion. If consumed after a meal, coffee may also speed up the rate that your stomach empties (2).
Approximately 30-60% of people may feel an urge to defecate (poop) after drinking coffee (1, 3). In one study, “coffee responders” had an increase in activity in the colon as early as four minutes after drinking both caffeinated and decaf coffee (3).
The release of hormones in the small bowel is the likely culprit of increased motility of the colon (1). This might explain why some people feel the effects of coffee on their digestive tract minutes after drinking coffee, well before the coffee has had the chance to reach the colon.
There is also a strong connection between the gut and the brain. So people who are affected by coffee may be responding to the belief that drinking coffee will make them poop.
Coffee as a Trigger Food in IBS
Twenty to 70% of people with IBS report that certain foods trigger their IBS symptoms (4, 5). Food triggers are more often identified among females and in those with anxiety (4). It is unclear whether some of the perceived food intolerances are affected by an individual’s belief that a food will cause the symptom.
Coffee is among the most frequently identified food triggers for those with IBS. One study surveyed patients with IBS versus healthy controls to identify foods that were perceived to cause bowel symptoms. Coffee was among the top 10 food triggers identified in IBS patients (6).
The most common symptoms associated with coffee consumption were dyspepsia (which included feelings of fullness, nausea, and upper abdominal discomfort), pain, and loose stools. Coffee was also identified as the number one cause of reflux in this study (6).
Up to 26% of people with IBS report limiting coffee intake. However, it is not known if coffee has a greater impact on motility in those with IBS vs those without (4).
Many patients have found relief from symptoms using various exclusion diets. In 14-33% of IBS patients, symptoms returned after re-introducing coffee. Again, it is not clear if this is a placebo effect (4).
Coffee and IBS-D vs IBS-C
Your tolerance to coffee may depend on your main IBS symptom. If you have IBS with diarrhea (IBS-D), coffee may be a bigger problem than if you have IBS with constipation (IBS-C).
Since coffee has an impact on gut motility, it is possible that people with IBS-D will have a stronger reaction to coffee. However, there are no studies to confirm this.
Many experts believe that coffee could be helpful for those with IBS-C. This is again related to the impact on gut motility.
Coffee might help someone suffering from constipation to finally find relief through a bowel movement. However, someone with IBS-C could still suffer other consequences from consuming coffee – such as reflux, nausea, or abdominal pain.
How Much Coffee is OK?
The good news is many people with IBS can tolerate some coffee. How much coffee might be different from one person to another.
Due to limited evidence regarding IBS and coffee, few organizations have made recommendations on coffee or caffeine.
The National Institute for Health and Care Excellence (NICE) recommends restricting tea and coffee to three cups a day (7). While the British Dietetic Association states regarding caffeine, there is insufficient evidence to make a recommendation (8).
If you are trying to determine if coffee is a problem for your IBS symptoms it may be helpful to keep a food diary. This should include what you ate or drank, how much, the time of day, and your symptoms.
It can also help to track stress and anxiety levels as these are factors also known to affect IBS symptoms. However, due to the potential for multiple food triggers, keeping a food diary is not always enough to identify what is causing your symptoms.
Eliminating coffee, both regular and decaf, for 2-3 weeks can further help identify if it is causing symptoms. If elimination of coffee results in an improvement in symptoms, it can be re-introduced in small amounts then slowly increased to determine how much coffee is tolerated.
Do not attempt this approach at the same time as other dietary or medication changes. If multiple changes are made at once it can be difficult to determine which change was the one that helped.
A registered dietitian can further assist you in determining whether coffee or other food triggers are causing your symptoms.
Decaf Coffee and IBS
Both caffeinated and decaffeinated coffee affect colonic motility in healthy people. Caffeinated coffee seems to have a stronger affect (1), but the fact that decaffeinated coffee also stimulates motility suggest that there are other compounds in coffee that act as a stimulant to the gut. If you find that regular coffee causes unpleasant symptoms, you may need to limit decaf coffee as well.
What About Other Foods and Drinks with Caffeine?
The impact of caffeine versus other components of coffee is unclear. However, caffeine may be a trigger on its own for some people.
If you suspect that caffeine is a trigger, you should also watch out for green or black tea, energy drinks, chocolate, cocoa powder, caffeinated soda, coffee ice cream, and coffee liqueur. Also keep in mind that certain over-the-counter pain relievers contain caffeine.
Coffee affects gut motility in both healthy people and in those with IBS. However, whether or not someone with IBS can tolerate coffee may be highly individual.
Those with IBS-D may notice stronger negative effects from coffee than those with IBS-C. In fact, some people with IBS-C might feel that coffee helps relieve their main symptom of constipation.
Regardless of the type of IBS, coffee may still leave you feeling uncomfortable with symptoms such as nausea, abdominal pain and reflux.
Elimination and re-introduction of coffee at low amounts may help determine whether coffee is a problem for you. It may be helpful to work with a registered dietitian to help pinpoint whether coffee is triggering your IBS symptoms.
- Rao SS, Welcher K, Zimmerman B, Stumbo P. Is coffee a colonic stimulant?. Eur J Gastroenterol Hepatol. 1998;10(2):113-118
- Akimoto K, Inamori M, Iida H, et al. Does postprandial coffee intake enhance gastric emptying?: a crossover study using continuous real time 13C breath test (BreathID system). Hepatogastroenterology. 2009;56(91-92):918-920.
- Brown SR, Cann PA, Read NW. Effect of coffee on distal colon function. Gut. 1990;31(4):450-453.
- Heizer WD, Southern S, McGovern S. The role of diet in symptoms of irritable bowel syndrome in adults: a narrative review. J Am Diet Assoc. 2009;109(7):1204-1214.
- Monsbakken KW, Vandvik PO, Farup PG. Perceived food intolerance in subjects with irritable bowel syndrome– etiology, prevalence and consequences. Eur J Clin Nutr. 2006;60(5):667-672.
- Simrén M, Månsson A, Langkilde AM, et al. Food-related gastrointestinal symptoms in the irritable bowel syndrome. Digestion. 2001;63(2):108-115.
- Hookway C, Buckner S, Crosland P, Longson D. Irritable bowel syndrome in adults in primary care: summary of updated NICE guidance. BMJ. 2015;350:h701. Published 2015 Feb 25.
- McKenzie YA, Bowyer RK, Leach H, et al. British Dietetic Association systematic review and evidence-based practice guidelines for the dietary management of irritable bowel syndrome in adults (2016 update). J Hum Nutr Diet. 2016;29(5):549-575.