Does coffee slow gastric emptying? The surprising truth about digestion

January 7, 2026 •

3 min read

According to a review of 194 research publications, coffee has a stimulating effect on several digestive processes, a fact that directly contradicts the common assumption that it might slow digestion. Far from hindering the stomach, the compounds in coffee, including both caffeine and others, actively influence the gastrointestinal tract and may even help with constipation.

Quick Summary

This article explores the complex relationship between coffee and digestion, revealing that the beverage typically accelerates, rather than hinders, the stomach's emptying process. It delves into the specific compounds in coffee that stimulate gastric activity, highlighting the varied individual responses and how decaffeinated options can also have an effect.

Key Points

Stimulates Digestion: Research shows coffee generally speeds up digestion by stimulating gastric acid secretion and colon contractions.
Increases Stomach Acid: Coffee triggers the release of the hormone gastrin, which leads to increased production of stomach acid.
Not Just Caffeine: Both caffeinated and decaffeinated coffee can affect digestion, indicating that other compounds beyond caffeine are involved.
Variable Impact: Coffee's effect on digestion is highly individual; some people may experience accelerated movement, while others feel discomfort like acid reflux.
Does Not Slow Gastric Emptying: The idea that coffee slows gastric emptying is a myth; multiple studies show it has no effect on or can even accelerate the rate at which liquids leave the stomach.
May Cause Discomfort: In sensitive individuals, the increase in stomach acid and motility can lead to symptoms like bloating, heartburn, and worsened IBS.

Understanding the Digestive System and Coffee's Impact

To understand how coffee impacts digestion, it's essential to first grasp the role of gastric emptying. This process involves the muscular contractions of the stomach that move food and liquids into the small intestine. When you drink coffee, your body's response is a complex interplay of hormones and nerve signals that can affect this mechanism. The idea that coffee slows this process is largely a myth, primarily because its stimulating properties tend to do the opposite.

The Direct Effect on Stomach Acid

One of the most well-documented effects of coffee is its ability to stimulate the release of gastrin, a hormone that triggers the production of gastric acid. This increase in stomach acid helps break down food more quickly, preparing it for the next stages of digestion. Both caffeinated and decaffeinated coffee have been shown to have this effect, though it is more pronounced with caffeinated varieties. For some, this boost in acidity can cause discomfort, especially if consumed on an empty stomach.

Colon Motility and the "Coffee-Induced Poop" Effect

Beyond the stomach, coffee also has a potent effect on the colon, significantly increasing its motor activity. Studies have shown that caffeinated coffee can stimulate the colon much more effectively than either water or decaf, with some individuals feeling the effects within minutes. This is not solely due to caffeine; other compounds in coffee are also responsible, as evidenced by decaf's milder but still noticeable impact on the colon. This acceleration of colon motility is a key reason why many people associate their morning cup with regularity.

Individual Variations and Gastrointestinal Sensitivity

It is important to remember that coffee's impact varies from person to person. Individual factors, such as genetics and overall gut health, play a significant role in how a person responds. While one person might experience faster digestion and relief from constipation, another with a sensitive stomach might suffer from acid reflux, bloating, or even increased IBS symptoms.

Comparison of Coffee's Digestive Effects


Digestive Factor	Regular Coffee	Decaffeinated Coffee	Water (Control)
Stomach Acid Stimulation	Strongest effect due to caffeine and other compounds.	Moderate effect, proving other coffee compounds are active.	No effect.
Colon Motility	Significantly increased motility; can cause defecation reflex.	Milder effect on motility compared to regular coffee.	Minimal to no effect on motility.
Gastric Emptying (Liquids)	No effect, according to multiple studies. May accelerate in some individuals with non-ulcer dyspepsia.	No significant effect observed.	Baseline for comparison.
Gallbladder Contraction	Stimulates cholecystokinin release and gallbladder contraction.	Also stimulates cholecystokinin release and gallbladder contraction.	No effect.
Risk of Bloating/Discomfort	Higher risk for sensitive individuals due to increased acid and motility.	Lower risk than regular, but still contains compounds that can cause issues.	Lowest risk.

How to Minimize Potential Digestive Discomfort

For those who experience negative side effects, there are several strategies to mitigate the problem. The type of roast, brewing method, and additions can all influence how your body reacts. Switching to a low-acid or cold-brewed coffee may reduce irritation, while pairing coffee with a balanced breakfast can provide a buffer against increased stomach acid. As noted by the Canadian Digestive Health Foundation, moderate consumption is often key to enjoying the benefits without the drawbacks.

The Bottom Line

Despite a lingering myth, coffee does not generally slow gastric emptying. The opposite is true: it is a potent stimulator of several digestive processes, from gastric acid secretion to colon motility. The perception that coffee causes digestive slowness likely stems from other uncomfortable symptoms like heartburn or bloating that can occur in sensitive individuals. Understanding these distinctions is crucial for anyone looking to enjoy their coffee while maintaining good digestive health.

Conclusion

Research clearly indicates that coffee does not slow gastric emptying. It contains compounds that actively stimulate gastric acid production and muscle contractions throughout the digestive tract, potentially speeding up the passage of food for many people. The notion that coffee hinders digestion is a misconception, likely conflated with other potential side effects. The key takeaway is that an individual’s gut sensitivity, the type of coffee consumed, and other lifestyle factors all play a role in the overall digestive experience. By being mindful of these variables, coffee drinkers can continue to enjoy their brew without unnecessary worry.

Frequently Asked Questions

Coffee does not slow gastric emptying. Instead, it typically speeds up digestive processes by stimulating stomach acid production and increasing colon motility.

Yes, caffeine acts as a stimulant that increases gut motility. However, other compounds in coffee, such as chlorogenic acids and polyphenols, also contribute to its digestive effects, as seen with decaffeinated coffee.

Yes, coffee can cause heartburn in some people by relaxing the lower esophageal sphincter, which allows stomach acid to flow back up into the esophagus. This effect is often more associated with caffeinated coffee.

While regular coffee has a more potent effect due to its higher caffeine content, decaf coffee can also stimulate digestive activity because of its other bioactive compounds. The response still depends on individual sensitivity.

To reduce negative effects, try drinking cold-brewed coffee or a darker roast, which are typically less acidic. Consuming coffee with food can also help buffer the stomach acid.

Coffee can cause bloating in some individuals due to several factors. It increases stomach acid, which can cause irritation, and stimulates the digestive system, potentially leading to excess gas. For some, additives like milk or sugar might be the culprit.

Yes, for many people, coffee can help with constipation by stimulating muscle contractions in the colon, which promotes bowel movements. This effect is often more noticeable in the morning.