Worst Foods for Diarrhea, According to Experts

Introduction

Diarrhoea, commonly described as the frequent passage of loose or watery stools, is a condition that can range from mild to uncomfortable. While often caused by infections, it may also result from non-infectious factors such as irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), certain medications, or food intolerances like lactose intolerance. Managing diarrhoea effectively begins with proper medical diagnosis, as treatment varies based on the underlying cause¹. 

Diet also plays a crucial role as some foods may aggravate symptoms, while others can help recovery². This guide offers general dietary advice to help manage diarrhoea more comfortably. It is not intended to replace professional medical consultation; individuals with ongoing or severe symptoms should seek advice from a healthcare professional. 

Causes of Diarrhoea

Diarrhoea can occur for a variety of reasons, and identifying the underlying cause is important in guiding appropriate treatment. Some common causes of diarrhoea include: 

1. Infections

Infectious causes are among the most common reasons for acute diarrhoea. Bacteria, viruses, and parasites can all lead to sudden episodes, often resulting from contaminated food, water, or poor hygiene practices. 

• Bacterial Infections: Foodborne bacterial infections are a common cause of diarrhoea and typically occur when food is contaminated with harmful bacteria or is not handled or cooked properly. Common culprits include Salmonella, Campylobacter, and Escherichia coli (E. coli). However, not all bacterial diarrhoeas are food-related, some, such as those caused by Shigella, can spread through contaminated water or close contact with an infected person. 
• Viral Infections: Rotavirus, norovirus, and adenovirus are viral infections known to cause diarrhoea. These viruses typically spread through contaminated food or water, or through direct contact with an infected person. While rotavirus and norovirus are more common, particularly in outbreaks, adenovirus is a less frequent cause and primarily affects infants and young children¹. 

2. Parasites

Parasitic infections, such as those caused by Giardia lamblia and Cryptosporidium, can lead to diarrhoea. Giardia is typically waterborne and is most often contracted through drinking or swallowing contaminated water; foodborne transmission is uncommon. Cryptosporidium is also associated with contaminated water, particularly recreational sources like swimming pools, and may pose a greater risk to individuals with weakened immune systems¹. 

3. Food Sensitivities and Intolerances

For some individuals, certain food ingredients can be difficult to digest, leading to diarrhoea. This may be due to food intolerances or sensitivities, where the body reacts adversely to specific components in food. 

• Lactose Intolerance: Lactose intolerance is a common type of food sensitivity that occurs when the body is unable to properly digest lactose, a natural sugar found in milk and other dairy products. This happens due to a deficiency of lactase, the enzyme needed to break down lactose, often resulting in symptoms such as diarrhoea, bloating, and stomach discomfort after consuming dairy. 
• Gluten Sensitivity: Gluten is a protein found in wheat, barley, and rye. For individuals with gluten sensitivity, consuming foods that contain gluten may trigger digestive symptoms, including diarrhoea. It is important to distinguish between coeliac disease and non-coeliac gluten sensitivity (NCGS). Coeliac disease is an autoimmune condition where gluten intake can damage the small intestine, with diarrhoea being a common symptom. In contrast, NCGS does not involve immune damage, and while it may cause digestive discomfort, diarrhoea is not always present³. 

4. Medications

Certain medications, including some antibiotics, antacids, and anti-inflammatory drugs, can cause diarrhoea as a side effect. For example, magnesium-containing antacids and non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may lead to diarrhoea in some individuals¹. 

5. Digestive Disorders

Chronic conditions like Crohn’s disease, ulcerative colitis, and irritable bowel syndrome (IBS) can cause recurrent episodes of diarrhoea. These long-term disorders affect the digestive system and may lead to persistent or intermittent symptoms that require ongoing medical management³. 

Worst Foods During Diarrhoea

When managing diarrhoea, it is best to avoid certain foods that may worsen symptoms or delay recovery. These foods include: 

1. Sugar and Artificial Sweeteners

Excessive sugar intake can trigger diarrhoea, as certain sugars draw water into the intestines, worsening symptoms. Artificial sweeteners, particularly sugar alcohols, may also have a laxative and should be avoided during diarrhoea². 

• Sugar alcohols: Substances such as sorbitol, mannitol, xylitol, and erythritol can cause diarrhoea if consumed in large amounts. 
• High-sugar products: Foods and drinks high in sugar, such as candies, syrups, and sodas can strain the digestive system and worsen diarrhoea. 
• Caffeine: Beverages containing caffeine may stimulate the intestines, potentially aggravating diarrhoea. 
• Coffee: Coffee contains caffeine as well as natural compounds that can increase intestinal activity and trigger diarrhoea. 
• Tea: It is advisable to avoid teas with caffeine, as they may also increase gut activity. 
• Soda: Caffeinated sodas should be avoided, as they combine the effects of caffeine with high sugar content, both of which can exacerbate diarrhoea. 

2. High-fat Foods

Fatty foods are often difficult to digest and can aggravate diarrhoea symptoms, potentially prolonging discomfort and recovery³. 

• Fried foods: French fries, fried chicken, and onion rings are best avoided during diarrhoea, as their high fat content can worsen symptoms. 
• Fast foods: The high levels of fat and low nutritional value in fast foods may disrupt digestion and may prolong diarrhoea. 

3. Spicy Foods

Spicy foods can irritate the digestive system and worsen diarrhoea⁴. 

• Hot sauce: Contains capsaicin, which can inflame the intestines and trigger diarrhoea. 
• Curries: Spicy curries may aggravate intestinal irritation and should be avoided during diarrhoea. 

4. Lactose-containing Foods

Lactose, found in dairy products, can be difficult to digest, especially during diarrhoea⁵. 

• Dairy products: Milk, cheese, and other dairy products may worsen symptoms, particularly for those who are lactose intolerant or temporarily have low levels of lactase. 
• Ice cream: High in lactose and sugar, ice cream can exacerbate diarrhoea and should be avoided. 

5. High Fermentable Oligosaccharide, Disaccharide, Monosaccharide, And Polyol (FODMAP) Foods

Certain fermentable carbohydrates known as FODMAPs can be hard to digest and may trigger diarrhoea, especially in individuals with chronic digestive conditions such as irritable bowel syndrome (IBS)⁶. 

• Onions: High in FODMAPs, onions may worsen diarrhoea symptoms in sensitive individuals. 
• Garlic: Similarly rich in FODMAPs, garlic can aggravate diarrhoea, particularly in those with IBS. 

6. Alcoholic Beverages

Alcohol can irritate the digestive tract and worsen diarrhoea⁴. 

• Wine: Contains sugar and alcohol, both of which can increase diarrhoea and lead to dehydration. 
• Beer: The combination of carbonation and alcohol in beer may negatively affect digestion and contribute to diarrhoea. 

7. High Acidity Foods

While these foods do not directly cause diarrhoea, the gas can speed up intestinal movement and lead to bloating and cramping, which may worsen symptoms⁴. 

• Beans: Known to cause gas, beans can contribute to discomfort and diarrhoea episodes. 
• Cabbage: Similar to beans, cabbage can produce gas and may aggravate diarrhoea symptoms. 
• Broccoli: Eating raw or undercooked broccoli can cause gas and potentially worsen diarrhoea. 

Lactose and FODMAP(Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols) Sensitivities During Diarrhea

Two common dietary triggers during diarrhea are lactose and FODMAPs. Understanding how they affect digestion can help you make better food choices during recovery¹¹.

Lactose Intolerance During Diarrhea

• After a gastrointestinal infection, some people may experience temporary lactose intolerance. This happens because the intestinal lining can become irritated, reducing the body’s ability to produce lactase, the enzyme needed to digest lactose (the sugar in dairy).
• It is important to note that not everyone needs to avoid dairy during diarrhoea. Many people tolerate it well. However, if dairy seems to worsen your symptoms, you may benefit from temporarily switching to lactose-free alternatives, such as lactose-free milk or suitable plant-based options.

FODMAPs and Digestive Symptoms

FODMAPs are a group of fermentable carbohydrates that some people find difficult to digest. In simple terms, they are certain sugars and fibres that can draw water into the gut and produce gas, which may worsen diarrhoea, bloating, and cramping. People with irritable bowel syndrome (IBS) tend to be more sensitive to high-FODMAP foods.

Examples of high-FODMAP foods include:

• Onions
• Garlic
• Certain legumes
• Apples

Examples of lower-FODMAP foods that are often better tolerated include:

• Rice
• Bananas
• Potatoes
• Carrots

If you suspect FODMAPs are triggering your symptoms, it is best to consult a healthcare professional or dietitian before making major dietary changes.

Alternative Healthy Foods for Diarrhoea Relief

Here are some healthy food options to consider when managing diarrhoea:  

1. Dairy Alternatives

If dairy worsens your diarrhoea, consider these alternatives³: 

• Lactose-free milk: This milk has had lactose removed, making it easier to digest while still providing essential nutrients. 
• Plant-based milk: Options such as almond, soy, and oat milk do not contain lactose. However, some plant-based milks (e.g., oat or rice milk) may contain added sugars or FODMAPs, which could aggravate diarrhoea in sensitive individuals.  

2. Low-fat and Baked Foods

Choose low-fat and baked foods rather than oily or fried items³. 

• Grilled chicken: A lean protein that is generally easier to digest than fatty meats. 
• Baked fish: Provides important nutrients without added fats or oils that may irritate the digestive system during diarrhoea.  

3. Mild or Non-spicy Options

Opt for mild flavours that are less likely to irritate your intestines³. 

• Herbs and spices: Mild herbs like basil, oregano, sage, and rosemary have anti-inflammatory properties and may help ease diarrhoea symptoms. 

4. Caffeine-free Beverages

Avoid caffeinated drinks, which can stimulate the digestive tract³. 

• Herbal tea: Peppermint and chamomile teas can help relax the digestive system. 
• Coconut water: A natural source of electrolytes that may assist with hydration, though it should not replace oral rehydration solutions in cases of severe diarrhoea.  

5. Low-FODMAP Choices

Low-FODMAP foods are less likely to trigger diarrhoea or inflammation⁴. 

• Carrots: Nutrient-rich and low in FODMAPs, carrots are gentle on the digestive system. 
• Bell peppers: These vegetables offer valuable nutrients and are unlikely to worsen diarrhoea. 

Managing Diarrhoea

Managing diarrhoea effectively involves several key steps. Staying well hydrated is essential, as diarrhoea causes significant fluid and electrolyte loss that can lead to dehydration. While drinking plenty of water helps replace lost fluids, it does not restore vital electrolytes such as sodium and potassium. Oral rehydration solutions (ORS), either commercially prepared or homemade to replenish both fluids and electrolytes¹. If vomiting accompanies diarrhoea, antiemetic medications may be helpful, but it is important to consult a healthcare provider before use. Additionally, allowing your body ample rest and relaxation supports recovery and helps the healing process. 

How Much Fluid Do You Need?

• Staying hydrated is one of the most important part of managing diarrhoea. When the body loses large amounts of fluid through loose stools, it also loses essential salts (electrolytes) such as sodium and potassium. This is why hydration is the foundation of recovery.
• Importantly, water alone does not replace lost electrolytes. This is where oral rehydration solution (ORS) becomes the preferred choice, as it contains a balanced mix of fluids, salts, and sugar that the body can absorb effectively.
• As a general guide, hydration needs are sometimes estimated based on body weight. For mild-to-moderate dehydration, healthcare providers may  recommend approximately 50–100 mL/kg of ORS given over several hours,depending on age, body weight, and the severity of dehydration.  under medical guidance.

To put this into perspective:

• For a child weighing 10 kg, this would mean roughly 500–1,000 mL of ORS over several hours.
• For an adult weighing 60 kg, this could amount to a few litres of ORS spread across the day.

These are general estimates only and should not replace personalised medical advice. The exact amount depends on the severity of dehydration and individual needs, so it is always best to follow the guidance of a healthcare professional, especially for children, older adults, or those with existing health conditions¹².

Diarrhoea in Children vs Adults

Diarrhoea can affect children and adults differently, and recognising these differences is important for safe management. Children, in particular, need closer attention because they can become dehydrated much faster than adults¹. 

For children, oral rehydration solution (ORS) is especially important, and parents should not wait too long before seeking medical advice if symptoms persist or worsen. For adults, mild cases often resolve with rest, hydration, and supportive care, but monitoring hydration remains important throughout. 

When to Seek Medical Help?

It is crucial to monitor your diarrhoea symptoms carefully and avoid self-medication. Seek immediate medical attention or visit the nearest hospital if you experience any of the following^8,9:

Signs of severe dehydration: 

• Minimal urine output 
• Sunken eyes 
• Dry mouth 
• Extreme tiredness or lethargy 
• Altered consciousness 
• Cold hands or feet 
• Very rapid heartbeat or breathing 
• No tears when crying (especially in children) 

Persistent or worsening symptoms

• Diarrhoea lasting more than 48 to 72 hours in adults 
• Diarrhoea continuing for over 24 hours in infants or children with ongoing symptoms 

Signs of infection or complications

• Blood or mucus in the stool 
• Severe abdominal pain 
• High fever 

When Diarrhoea Becomes a Dehydration Emergency?

In some cases, diarrhoea can lead to severe dehydration, which is a medical emergency. Watch closely for the following red-flag symptoms¹³:

• Very little or no urination
• Extreme thirst
• Dry mouth
• Sunken eyes
• Dizziness
• Confusion
• Rapid heartbeat
• Severe weakness
• Inability to keep fluids down

Warning Signs in Children

Children can deteriorate quickly, so parents and carers should be especially alert to:

• No tears when crying
• Dry nappies for several hours
• Unusual sleepiness or lethargy

If you or your child show any of these symptoms, seek urgent medical attention immediately. Severe dehydration requires prompt treatment and should not be managed at home alone.

Prevention

Preventing diarrhoea or reducing its frequency involves managing underlying health conditions, maintaining good hygiene, and addressing food sensitivities. Key measures include¹⁰: 

• Managing chronic conditions: Regularly monitor and adhere to treatment plans for gastrointestinal disorders such as IBS or inflammatory bowel disease. 
• Proper hygiene and food safety: Wash hands thoroughly before meals and ensure food is handled and stored safely to avoid contamination. 
• Identifying food sensitivities: Keep track of any adverse reactions to specific foods and consult a healthcare provider to manage these sensitivities effectively. 
• Vaccination: Immunisation, such as the rotavirus vaccine, plays an important role in preventing diarrhoeal illnesses, particularly in young children. 

Traveller’s Diarrhoea

Traveller’s diarrhoea is a common digestive condition that affects people travelling to regions with different sanitation standards or unfamiliar food and water. It is usually defined as the passage of loose stools during or shortly after travel¹⁴. often accompanied by symptoms such as abdominal cramps, nausea, or urgency.” 

Common Causes

Traveller’s diarrhoea is most often caused by consuming food or water contaminated with bacteria, viruses, or parasites. Bacterial causes, such as certain strains of E. coli, are among the most frequent.

Risk Factors During Travel

• Drinking untreated or contaminated water
• Eating undercooked or improperly handled food
• Consuming ice made from unsafe water
• Visiting areas with poor sanitation or hygiene standards

Prevention Tips

You can reduce your risk by following a few simple precautions:

• Safe drinking water: Stick to bottled, boiled, or properly treated water.
• Hand hygiene: Wash hands thoroughly with soap, or use a sanitiser when soap is unavailable.
• Eat thoroughly cooked foods: Choose hot, freshly cooked meals over raw or undercooked items.
• Avoid unsafe ice and contaminated foods: Be cautious with ice, salads, peeled fruits prepared by others, and street food in high-risk areas.

Travel Tip: The safest approach is often boil it, cook it, peel it, or leave it. Paying attention to food and water hygiene can significantly reduce the risk of traveller’s diarrhoea.

Also Read: Worst Foods for Oedema You Should Be Aware Of

Conclusion

Diarrhoea can result from multiple factors, and certain foods may worsen symptoms. Avoiding foods such as dairy products, high-fat items, sugar alcohols, caffeine, spicy foods, alcohol, and gas-producing foods can support a quicker recovery. Instead, choosing healthier alternatives, monitoring for signs of dehydration, and seeking medical attention when necessary are essential steps. Making informed dietary choices plays a significant role in how swiftly you recover from diarrhoea. 

Also Read: Constipation in Kids: A Research-Based Guide for Parents 

Frequently Asked Questions (FAQs)

References

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2. Eating, Diet, & Nutrition for Diarrhea | NIDDK [Internet]. National Institute of Diabetes and Digestive and Kidney Diseases. [cited 2025 Jun 26]. Available from: https://www.niddk.nih.gov/health-information/digestive-diseases/diarrhea/eating-diet-nutrition  
3. Cozma-Petruţ A, Loghin F, Miere D, Dumitraşcu DL. Diet in irritable bowel syndrome: What to recommend, not what to forbid to patients! World Journal of Gastroenterology [Internet]. 2017 [cited 2025 Jun 26];23(21):3771. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5467063/ 
4. Is something in your diet causing diarrhea? [Internet]. Harvard Health. 2016 [cited 2025 Jun 26]. Available from: https://www.health.harvard.edu/diseases-and-conditions/is-something-in-your-diet-causing-diarrhea  
5. National Institute of Diabetes and Digestive and Kidney Diseases. Eating, Diet, & Nutrition for Lactose Intolerance | NIDDK [Internet]. National Institute of Diabetes and Digestive and Kidney Diseases. 2019 [cited 2025 Jun 26]. Available from: https://www.niddk.nih.gov/health-information/digestive-diseases/lactose-intolerance/eating-diet-nutrition 
6. Bertin L, Miriana Zanconato, Crepaldi M, Marasco G, Cesare Cremon, Barbara G, et al. The Role of the FODMAP Diet in IBS. Nutrients [Internet]. 2024 Jan 26 [cited 2025 Jun 26];16(3):370–0. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC10857121/  
7. Solan M. The rundown on diarrhea [Internet]. Harvard Health. 2022 [cited 2025 Jun 26]. Available from: https://www.health.harvard.edu/diseases-and-conditions/the-rundown-on-diarrhea  
8. Diarrhea [Internet]. Hospital Handbook. 2014 [cited 2025 Jun 26]. Available from: https://hospitalhandbook.ucsf.edu/02-diarrhea/02-diarrhea  
9. Harvard Health Publishing. Diarrhea – Harvard Health [Internet]. Harvard Health. Harvard Health; 2018 [cited 2025 Jun 26]. Available from: https://www.health.harvard.edu/a_to_z/diarrhea-a-to-z 
10. Diarrhea & Prevention – Atlantic International University [Internet]. Atlantic International University. 2025 [cited 2025 Jun 26]. Available from: https://www.aiu.edu/student_pub/diarrhea-prevention/ 
11. Cozma-Petruț A, Loghin F, Miere D, Dumitrașcu DL. Diet in irritable bowel syndrome: What to recommend, not what to forbid to patients! World J Gastroenterol. 2017 Jun 7;23(21):3771-3783. doi: 10.3748/wjg.v23.i21.3771. PMID: 28638217; PMCID: PMC5467063. https://pmc.ncbi.nlm.nih.gov/articles/PMC5467063/
12. National Collaborating Centre for Women’s and Children’s Health (UK). Diarrhoea and Vomiting Caused by Gastroenteritis: Diagnosis, Assessment and Management in Children Younger than 5 Years. London: RCOG Press; 2009 Apr. (NICE Clinical Guidelines, No. 84.) 5, Fluid management. Available from: https://www.ncbi.nlm.nih.gov/books/NBK63837/ 
13. Dehydration and diarrhea. Paediatr Child Health. 2003 Sep;8(7):459-68. doi: 10.1093/pch/8.7.459. PMID: 20019956; PMCID: PMC2791660. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC2791660/
14. Dunn N, Okafor CN. Travelers Diarrhea. [Updated 2023 Jul 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459348/

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