Does Dairy Worsen Constipation? The Full Story

November 2, 2025 •

4 min read

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), constipation is a common problem defined by having fewer than three bowel movements a week. For some individuals, dairy can significantly worsen constipation due to its protein composition and lack of fiber.

Quick Summary

Dairy can worsen constipation for some individuals, particularly children and those with lactose intolerance or a cow's milk protein allergy. The high fat and low fiber content in some dairy products and methane gas production can slow digestion. Addressing the underlying cause is key to managing symptoms.

Key Points

Lactose intolerance causes constipation for some: While often associated with diarrhea, undigested lactose can produce methane gas that slows gut motility in around 30% of intolerant individuals.
Cow's milk protein allergy is a common cause in children: Studies show that a significant percentage of children with chronic constipation, especially those unresponsive to laxatives, have a cow's milk protein allergy.
High fat and low fiber contribute to constipation: Many dairy products, such as cheese and ice cream, are high in fat (slowing digestion) and low in fiber (which is needed for proper bulk), leading to slower bowel movements.
Probiotics in fermented dairy can be beneficial: Yogurt and kefir contain probiotics that can improve gut health and may counteract constipating effects, making them better choices for some.
Individual response to dairy varies greatly: The effect of dairy on constipation is not universal; what affects one person may not affect another. Personal sensitivity and overall diet are major factors.
Alternative calcium sources are available: For those sensitive to dairy, plenty of calcium-rich foods and fortified products exist, including leafy greens, fortified plant-based milks, and sardines.

The Connection Between Dairy and Constipation

For many, dairy is a dietary staple, but for others, it can be a source of digestive distress. While dairy is a rich source of calcium and protein, certain components can lead to or aggravate constipation in susceptible individuals. The link is complex and often depends on individual factors, such as underlying food sensitivities and gut microbiome composition.

Lactose Intolerance and Gut Motility

Lactose intolerance is a condition where the body cannot produce enough lactase, the enzyme needed to break down lactose, the sugar found in milk.

In most cases, undigested lactose ferments in the colon, producing gas and causing symptoms like bloating, cramping, and diarrhea.
However, in about 30% of lactose-intolerant individuals, this fermentation process can lead to constipation instead of diarrhea.
Researchers believe this is because the fermentation can produce methane gas, which slows the movement of food through the digestive tract.

Cow's Milk Protein Allergy (CMPA)

Separate from lactose intolerance, a cow's milk protein allergy is an immune system response to the proteins in cow's milk, such as casein and whey.

This allergy is more common in children and can cause various gastrointestinal issues, including chronic constipation, inflammation, and painful defecation.
Studies have shown that children with persistent constipation, especially those unresponsive to laxatives, often see significant improvement after switching to a cow's milk-free diet.

Other Factors: Fiber and Fat Content

Beyond specific intolerances, the nutritional profile of many dairy products can contribute to digestive slowdown.

Most dairy products, particularly cheese and ice cream, contain very little to no dietary fiber. Fiber is crucial for adding bulk to stool and promoting regular bowel movements. When high-fiber foods are replaced with low-fiber dairy, the digestive tract's motility can be compromised.
The high-fat content in some dairy items also contributes to a slower digestive process. Fat is more difficult for the body to break down and can delay gastric emptying, leading to constipation.

A Comparison of Dairy Products and Constipation Risk


Dairy Product	Key Characteristics	Constipation Risk	Considerations
Hard Cheese	High in fat, very low in fiber.	High	Often a leading cause of dairy-related constipation due to its binding properties.
Milk	Contains lactose and protein (casein/whey), moderate fat.	Moderate to High	High risk for those with lactose intolerance or CMPA. Children are particularly susceptible.
Ice Cream	High in fat and sugar, low in fiber.	High	The combination of high fat and low fiber makes it particularly constipating for many individuals.
Yogurt & Kefir	Fermented dairy, contains probiotics.	Low to None	The live, active cultures (probiotics) can improve gut health and may help alleviate constipation.
Fermented Dairy	Includes items like some cheeses with probiotics.	Low	Beneficial bacteria help break down lactose and support gut flora balance.

Strategies for Managing Dairy-Related Constipation

If you suspect dairy is the culprit behind your constipation, several strategies can help manage or alleviate symptoms:

Elimination Diet: Try removing all dairy products from your diet for a few weeks to see if your symptoms improve. This can help pinpoint whether dairy is the cause.
Choose Probiotic-Rich Options: Fermented dairy products like yogurt and kefir contain probiotics, which are beneficial bacteria that can aid digestion and counteract the constipating effects.
Opt for Low-Lactose or Lactose-Free Products: Switching to lactose-free milk or aged cheeses (which are lower in lactose) can help if lactose intolerance is the issue.
Increase Fiber Intake: Ensure your diet is rich in high-fiber foods, such as fruits, vegetables, and whole grains, to promote regular bowel movements. Hydration is also essential for fiber to work effectively.
Non-Dairy Alternatives: Explore calcium-fortified non-dairy milk alternatives like soy, almond, or oat milk, which are generally not associated with constipation.
Consult a Professional: If constipation persists, consulting a doctor or registered dietitian is essential to rule out other causes and get personalized advice.

Conclusion: Personalizing Your Dairy Intake

While dairy can certainly worsen constipation for a specific subset of the population, it is not a universal trigger. The key lies in understanding your own body's response. For individuals with lactose intolerance or a cow's milk protein allergy, dairy can be a direct cause of digestive issues. However, for many others, particularly those who consume probiotic-rich, fermented dairy in moderation, it may not pose a problem. Experimenting with your diet, paying attention to your body, and making gradual adjustments can help you determine the best approach for your digestive health. Making informed choices and consulting a healthcare provider can provide clarity and relief from discomfort. For further reading on dietary fiber, the National Institute of Diabetes and Digestive and Kidney Diseases provides comprehensive information.

Frequently Asked Questions

Cheese can cause constipation because it is high in fat and contains no fiber, which is essential for promoting regular bowel movements. The high fat content slows down the digestive process.

Yes, chronic constipation in children can be a sign of a cow's milk protein allergy. Several studies show that many children experience relief when cow's milk is eliminated from their diet.

No, probiotic-rich yogurts are generally not considered bad for constipation. In fact, the live, active cultures can help balance gut flora and may improve digestion, potentially relieving constipation.

No, while diarrhea is a common symptom, approximately 30% of lactose-intolerant individuals experience constipation. This can be caused by the production of methane gas during the fermentation of undigested lactose.

A simple way to test is to try an elimination diet by completely removing all dairy products for a few weeks. If your symptoms improve, it's a good indication that dairy is a contributing factor.

Excellent non-dairy calcium sources include leafy green vegetables (like kale and broccoli), canned fish with soft bones (sardines), and fortified foods such as soy milk and cereals.

No, a dairy-free diet is most beneficial for those with a specific sensitivity, intolerance, or allergy. If dairy is not the root cause, eliminating it may not resolve the issue, and other factors like fiber and hydration should be addressed.