Can you have walnuts when you have diarrhea? The definitive dietary guide

December 15, 2025 •

5 min read

According to the National Institute of Health, around 179 million cases of acute diarrhea occur annually in the United States. When suffering from this common ailment, your food choices become critical. Therefore, understanding the answer to, 'can you have walnuts when you have diarrhea?' is essential for a quicker recovery and to prevent worsening your symptoms.

Quick Summary

It is not recommended to eat walnuts during acute diarrhea due to their high fiber and fat content, which can exacerbate symptoms. The best approach is to avoid them initially, focus on a low-fiber diet, and reintroduce walnuts slowly and in moderation after symptoms subside.

Key Points

Not Recommended for Acute Diarrhea: Due to high fiber and fat, walnuts can worsen diarrhea and cause digestive discomfort.
Follow a Low-Fiber Diet Initially: When experiencing diarrhea, consume bland, low-fiber foods like bananas, rice, and toast to allow your bowels to rest.
Reintroduce Gradually: Once symptoms have subsided, add a small portion of walnuts back into your diet and observe your body's reaction.
Chew Thoroughly and Hydrate: To aid digestion, ensure you chew walnuts completely and pair them with plenty of water.
Walnuts Are Healthy for a Healthy Gut: Once recovered, walnuts are an excellent source of prebiotics and nutrients that support a healthy gut microbiome.
Be Mindful of Fat and Phytates: High fat content and natural compounds like tannins and phytates in walnuts can aggravate a sensitive digestive system.

Why walnuts are not recommended during acute diarrhea

When your digestive system is compromised by diarrhea, the goal is to consume foods that are easy to digest and do not overstimulate your bowels. Walnuts, despite their general health benefits, contain several components that make them unsuitable for an upset stomach.

The impact of high fiber

Walnuts are a significant source of dietary fiber, with a one-ounce serving containing approximately 2 grams. While fiber is normally beneficial for promoting regular bowel movements, it can be detrimental during a bout of diarrhea. Excessive fiber intake, especially insoluble fiber, acts as a gastrointestinal stimulant that increases bowel motility. This can worsen the frequency and urgency of loose stools, prolonging your discomfort. For this reason, a low-fiber diet, limiting daily fiber intake to around 10 grams, is often recommended for managing diarrhea.

High fat content and digestion

Walnuts are rich in healthy fats, primarily omega-3 fatty acids. However, a one-ounce serving also packs about 19 grams of fat. When the digestive system is already in distress, absorbing a large amount of dietary fat becomes difficult. Undigested fats can end up in the colon, where they are broken down into fatty acids that can trigger fluid secretion and increase intestinal contractions, leading to more diarrhea. Excessive consumption of any high-fat food, including walnuts, can overwhelm your system and worsen your symptoms.

Tannins and phytates

Walnuts, like many nuts, contain natural compounds called tannins and phytates. These compounds can make nuts difficult to digest for some individuals. In a sensitive digestive tract, these substances can contribute to gas, bloating, and general stomach discomfort. For someone already dealing with diarrhea, these effects can further irritate the inflamed intestinal lining.

Foods to avoid and foods to embrace

While avoiding walnuts is a good step, it's important to understand the broader dietary picture for managing diarrhea. The general principle is to stick to bland, easy-to-digest foods and avoid anything that could further irritate your system.

Foods to avoid during diarrhea:

High-fiber foods: Walnuts, other nuts, seeds, legumes, whole grains, and raw fruits and vegetables.
Fatty and fried foods: Processed meats, fast food, and anything fried, which can worsen fat digestion.
Spicy foods: Capsaicin and other spices can irritate the stomach and increase motility.
Caffeine and alcohol: These are stimulants that can act as diuretics and dehydrate you further.
Dairy: Unless it is a probiotic-rich yogurt, milk and other dairy products contain lactose, which can be hard to digest during a diarrheal episode.

Foods to eat during diarrhea:

The BRAT diet: Bananas, white Rice, Applesauce, and Toast (preferably white) are well-known for being gentle on the stomach.
Lean protein: Plain, well-cooked chicken, fish, and eggs are good sources of protein without added fat.
Starchy vegetables: Boiled or mashed potatoes and sweet potatoes (peeled) are excellent options.
Hydrating fluids: Broths, sports drinks, and oral rehydration fluids can help replenish lost electrolytes.
Probiotic yogurt: Non-fat yogurt with live cultures can help restore beneficial gut bacteria, unless you are lactose intolerant.

How to safely reintroduce walnuts after diarrhea subsides

Once your symptoms have improved and you have returned to a more normal diet, you can begin to reintroduce walnuts slowly. Moderation and observation are key to ensuring they don't trigger a relapse.

Start small: Begin with a very small portion, such as just a few walnut halves. See how your body reacts over 24 hours.
Chew thoroughly: Grinding the walnuts into a paste in your mouth before swallowing can aid digestion.
Drink plenty of water: Hydration is important when increasing fiber intake to help it move through your digestive tract more efficiently.
Consider soaking: Soaking raw walnuts can help break down some of the compounds that make them hard to digest.
Listen to your body: If you experience any bloating, gas, or stomach cramps, it may be a sign to hold off on walnuts for a bit longer.

Walnut consumption: When is it a good idea?

It is important to emphasize that walnuts are a very healthy food. Once you have recovered from diarrhea, they offer numerous benefits for gut health. Research shows that compounds in walnuts, like fiber and healthy fats, can act as prebiotics, nourishing and promoting the growth of beneficial gut bacteria. Studies have also linked walnut consumption to an increase in bacteria that produce butyrate, a compound that helps reduce inflammation in the colon. Thus, once your digestive system has healed, reintroducing walnuts in a controlled way can help restore and maintain a healthy gut microbiome.

Comparison of Walnuts and BRAT Diet Foods for Diarrhea Management


Feature	Walnuts	BRAT Diet Foods (Bananas, Rice, Applesauce, Toast)
Fiber Content	High: Can stimulate bowel movements and worsen diarrhea.	Low: Gentle on the digestive system, helps bind stool.
Fat Content	High: Can be difficult for a compromised digestive system to absorb, potentially worsening diarrhea.	Low: Minimal fat content, making them very easy to digest.
Digestibility	Difficult: Contains tannins and phytates, which can cause gas and bloating.	Easy: Bland and simple carbohydrates are easy for the body to break down.
Nutrient Density (during recovery)	High: Rich in nutrients, but the high fiber and fat are problematic during acute illness.	Moderate: Provides energy and electrolytes without irritating the bowels, perfect for initial recovery.
General Suitability for Diarrhea	Poor: Best to avoid until symptoms have fully subsided.	Excellent: Forms the basis of a safe diet for managing diarrhea.

Conclusion: The right time for walnuts

For those wondering, "can you have walnuts when you have diarrhea?", the answer is clear: it is best to avoid them during an active episode. Their high fiber and fat content, along with hard-to-digest compounds, can worsen symptoms and delay your recovery. The optimal strategy involves initially adopting a low-fiber, bland diet, such as the BRAT diet, and ensuring adequate hydration. Once your digestive system has settled, you can slowly reintroduce walnuts in small amounts to reap their well-documented health and prebiotic benefits for your gut. Listening to your body and consulting with a healthcare professional if symptoms persist is always the safest course of action. For more information on low-fiber diets for digestive issues, you can visit the Mayo Clinic website.

Frequently Asked Questions

Walnuts and other nuts are not recommended during diarrhea because they are high in fiber and fat. High fiber can increase bowel motility, while high fat can be difficult to digest, both of which can worsen diarrheal symptoms.

You should focus on bland, low-fiber foods that are easy to digest. The BRAT diet (Bananas, Rice, Applesauce, Toast), boiled potatoes, plain chicken, and eggs are all good alternatives.

You should wait until your diarrhea symptoms have completely resolved and you are back on a normal diet. Start with a very small portion and monitor your body's reaction before increasing the amount.

Yes, eating too many walnuts, even in a healthy person, can cause digestive distress, including bloating, gas, and diarrhea, due to their high fiber and fat content.

Some people find that soaking walnuts improves their digestibility by helping to break down enzyme inhibitors. This can be a useful strategy when reintroducing them after diarrhea.

Yes. For people with a healthy gut, walnuts are a source of prebiotics that can promote beneficial gut bacteria. Some individuals with specific conditions like constipation-dominant IBS may find them helpful, but this is different from acute diarrhea.

While it's possible, it is not the most common reason for diarrhea during a single episode. If you consistently experience symptoms like diarrhea, gas, or cramps after eating walnuts, it could indicate an intolerance or allergy, and you should consult a doctor.

During diarrhea, your digestive system struggles to absorb fats. Unabsorbed fats pass into the colon, where they can cause increased fluid secretion and contractions, further worsening symptoms.