What is the best milk if you have diarrhea?

January 9, 2026 •

4 min read

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), symptoms of lactose intolerance, including diarrhea, can occur after consuming milk and dairy products containing lactose. When your digestive system is compromised, choosing the right milk can be crucial for comfort and recovery.

Quick Summary

This guide explores the best and worst milk options to consume when experiencing diarrhea. It details why traditional dairy can be problematic and highlights safe, easy-to-digest alternatives like lactose-free milk and plant-based options such as almond and rice milk. Find out how to make a gut-friendly choice.

Key Points

Avoid Regular Dairy: Regular cow's milk contains lactose, which can worsen diarrhea by irritating an already sensitive gut, even in those not typically lactose intolerant.
Choose Lactose-Free Milk: Lactose-free cow's milk is a safe option as it has the lactose already broken down, allowing for easier digestion with all the same nutrients.
Opt for Plant-Based: Almond, rice, and unsweetened oat milks are good alternatives, as they are naturally lactose-free and generally easy on the stomach.
Try Probiotic Kefir: Kefir is a fermented milk with beneficial probiotics that can help restore gut flora, though it may not be suitable for severe cases of lactose intolerance.
Prioritize Hydration: Regardless of milk choice, focus on rehydration with water, broth, and electrolyte solutions, and introduce milks and bland foods gradually.
Read Labels Carefully: Be wary of added sugars, gums, and thickeners in milk alternatives, as these can also upset a sensitive digestive system.

Why Cow's Milk Often Worsens Diarrhea

When experiencing diarrhea, the intestinal lining becomes irritated and can temporarily produce lower levels of the enzyme lactase. Lactase is required to break down lactose, the sugar found in cow's milk. A deficiency in this enzyme leads to lactose malabsorption, where undigested lactose ferments in the colon, causing a host of gastrointestinal symptoms including gas, bloating, cramping, and, most notably, diarrhea. This means that even if you are not typically lactose intolerant, a bout of infectious or post-antibiotic diarrhea can trigger a temporary intolerance, making standard dairy milk a poor choice.

High-Fat Dairy Can Also Irritate

Beyond lactose, high-fat content in some dairy products can also aggravate an already sensitive digestive system. Fatty foods, in general, can be harder to digest and may accelerate intestinal transit, which is the last thing you need when trying to recover from diarrhea. Therefore, avoiding high-fat milk, ice cream, and creamy cheeses is advisable during recovery.

The Best Milk Alternatives for an Upset Stomach

Opting for a milk alternative can provide a much-needed break for your digestive tract. Here are some of the most suitable options when dealing with diarrhea.

Lactose-Free Cow's Milk

For those who still want the taste and nutritional profile of dairy, lactose-free milk is an excellent choice. This milk is regular cow's milk with the lactase enzyme added to it, which pre-digests the lactose. This allows the body to absorb the milk’s nutrients without the digestive distress. It provides the same calcium and protein as regular milk, and many people find it tastes slightly sweeter.

Plant-Based Milk Options

Plant-based milks are naturally lactose-free and can be a safe alternative, provided you check for any added ingredients that might cause irritation. Many plant-based milks are fortified with calcium and vitamin D to match cow's milk's nutritional benefits.

Almond Milk: Unsweetened almond milk is a popular and safe choice. It's naturally lactose-free, low in calories, and generally easy to digest. It's a low-FODMAP option, making it suitable for those with IBS-like symptoms during diarrhea. It's lower in protein than cow's milk, so it should be supplemented with other protein sources.
Rice Milk: This milk is often considered the most hypoallergenic of all milk alternatives, making it very gentle on the stomach. It is naturally sweet with a thin consistency and is low in fat, but also lacks significant protein.
Oat Milk: Oat milk contains soluble fiber, including beta-glucan, which can promote healthy gut bacteria. However, some individuals with sensitive digestion might experience bloating from the fiber, so starting with a small amount is wise. Ensure you choose an unsweetened variety without added gums or thickeners, which can cause digestive issues.

Probiotic-Rich Kefir

Kefir, a fermented milk drink, contains beneficial probiotic bacteria and yeast. The fermentation process breaks down much of the lactose, making it potentially tolerable for some people with mild lactose sensitivity. The probiotics in kefir may help restore a healthy gut microbiome, which is crucial for recovery. However, individuals with severe lactose intolerance may still find it irritating, so starting with a small serving is best.

Comparison of Milk Options for Diarrhea


Milk Type	Lactose Content	Key Benefit for Diarrhea	Potential Drawback	Best For
Lactose-Free Cow's Milk	None	Same taste and nutrients as dairy, but without the irritating lactose.	May not be suitable for those with a cow's milk allergy.	People who want a dairy option without the lactose side effects.
Almond Milk	None	Gentle on the stomach; low in calories and carbohydrates.	Lower in protein and nutrients unless fortified.	Those seeking a very mild, low-allergen alternative.
Rice Milk	None	Hypoallergenic and very easy to digest.	Higher in carbohydrates, lower in protein.	Individuals with multiple food sensitivities.
Oat Milk	None	Contains gut-friendly fiber (beta-glucan).	High fiber can cause gas for some; check for added gums.	Supporting gut health, but with caution for sensitive individuals.
Kefir (Probiotic)	Low	Introduces beneficial probiotics to rebalance gut flora.	May still cause issues for those with severe lactose intolerance.	Restoring gut health after diarrhea has subsided.

Essential Considerations and Recommended Intake

Regardless of your milk choice, always prioritize rehydration. Diarrhea causes significant fluid and electrolyte loss, and these need to be replenished promptly. In addition to milk, drinking water, broth, or an electrolyte solution is vital. Start with small, frequent sips, and gradually reintroduce solids as you can tolerate them. The BRAT diet (Bananas, Rice, Applesauce, Toast) is often recommended during recovery because these foods are bland and easy to digest. Combining your chosen milk alternative with bland, soothing foods can aid your recovery.

For more information on digestive health, consult authoritative sources like the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). https://www.niddk.nih.gov/health-information/digestive-diseases/diarrhea/eating-diet-nutrition

Conclusion

When you have diarrhea, the best milk is one that is gentle on your inflamed digestive system. For many, this means temporarily avoiding regular dairy due to its lactose content. Lactose-free cow's milk and plant-based options like almond, rice, and, with caution, oat milk offer excellent alternatives. Probiotic-rich kefir can be beneficial for restoring gut balance but may not be suitable for everyone during the acute phase. The key is to listen to your body, choose plain and unsweetened options, and prioritize rehydration. If symptoms persist or are severe, consulting a healthcare professional is always the best course of action.

Frequently Asked Questions

When you have diarrhea, your gut may produce less lactase, the enzyme needed to digest lactose in dairy milk. This leads to undigested lactose fermenting in the colon, causing gas, bloating, and more diarrhea.

Yes, lactose-free cow's milk is generally safe. It contains added lactase to pre-digest the lactose, making it much easier on your stomach and a good alternative to regular dairy.

Plain, unsweetened almond and rice milks are among the best choices. They are naturally lactose-free and gentle on the stomach. Oat milk is also an option, but some people may be sensitive to its fiber content.

Kefir contains beneficial probiotics that can help restore healthy gut bacteria. The fermentation process also reduces lactose. It may be helpful during the recovery phase, but introduce it slowly, as it may still irritate some individuals.

It is wise to avoid regular dairy milk and high-fat dairy products during an acute episode of diarrhea. You can switch to lactose-free milk or plant-based alternatives to avoid exacerbating symptoms.

Look for unsweetened varieties and check the ingredient list for added gums like carrageenan or guar gum, which can sometimes cause digestive upset. Choosing a simple, clean label is best for sensitive guts.

Prioritize water, broth, and oral rehydration solutions. These fluids help replace lost electrolytes and prevent dehydration, which is a major concern with diarrhea.