Struggling With Digestion? What to Eat and What to Avoid

These 11 foods are the most common culprits behind digestive issues like bloating, diarrhea, and heartburn. Learn what to eat instead.
Struggling With Digestion? What to Eat and What to Avoid
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A balanced diet that keeps the gut healthy provides a wide range of foods and nutrients. However, some foods can cause digestive symptoms, especially if you live with certain health conditions.

Here are the foods to avoid if you’ve got digestive symptoms (such as bloating, constipation, diarrhea, or heartburn), what to eat instead, and when to see a doctor.

11 Foods That Are Hard to Digest (And What to Eat Instead)

The following foods tend to be the most challenging to digest, leading to symptoms like gas, bloating, acid reflux (heartburn), diarrhea, constipation, and nausea.

Some may cause digestive symptoms in those who have no known health problems. Others, like foods containing gluten or lactose, are linked to dietary sensitivities or digestive issues.

1. Dairy Products

Some people experience gas, bloating, and diarrhea when they consume dairy products. This is often due to lactose intolerance, which is the inability to digest lactose, a sugar found in milk and dairy products.

In a healthy gut, the small intestine makes an enzyme called lactase to break down lactose. However, some people don’t make enough lactase, causing lactose to stay in the gut instead of being absorbed by the body.

Eventually, the lactose travels to the large intestine (colon), where bacteria break down the undigested sugars, creating gas. The large intestine also produces more fluid to help the undigested sugar molecules pass through, causing diarrhea, gas pain, and bloating.

What to Eat Instead Because dairy products are good sources of bone-building nutrients like calcium and vitamin D, many experts recommend including them in small amounts even if you’re lactose intolerant.

People with lactose intolerance can still handle a certain amount of lactose before experiencing symptoms.

Try consuming small servings of milk (about 1 cup) with meals and keep tabs on how you feel afterward.

 Also, note that yogurts and hard cheeses have less lactose than other dairy products and may be friendlier to the gut.

Some low-lactose and lactose-free milk products can help you get calcium and vitamin D without the symptoms of lactose intolerance.

 However, you may have to consume these products in large amounts to get adequate vitamin D and calcium, says Luis F. Lara, MD, professor of clinical medicine and division chief of digestive diseases at the University of Cincinnati College of Medicine in Ohio.

2. Fried and Other High-Fat Foods

Fats spend more time in the stomach, making them more likely to trigger acid reflux (when stomach contents rise into the esophagus).

And, because fats can be harder for the body to break down, consuming them in high amounts can create bloating and gas. It can also cause the colon to produce more liquid, making stools loose and watery.

What to Eat Instead Replace fatty, fried foods with lean meats that you’ve grilled, boiled, baked, or poached. Also, opt for nuts and seeds, avocados, olive oil, and fish, which offer unsaturated fats that tend to be more gut-friendly.

3. Cruciferous Vegetables

Cruciferous vegetables, like broccoli, cabbage, kale, radish, and mustard greens, are good sources of fiber, making them an important part of a healthy diet. However, as a nondigestible carbohydrate, fiber can cause digestive issues like gas and bloating, especially when eaten in high amounts.

When you eat cruciferous vegetables, the fiber remains intact as it passes through the stomach and small intestine and into the colon. Once inside the colon, microbes feed on the fiber, creating gas.

What to Eat Instead Cruciferous veggies provide many health benefits, and most people shouldn’t cut them out of their diet. Instead, try boiling, sauteeing, or roasting these vegetables to make them easier to digest.

If you’re temporarily avoiding high-fiber foods, opt for lower-fiber vegetables, like carrots, mushrooms, and cooked green beans.

4. Ultra-Processed Foods

Ultra-processed foods (UPFs) are foods that have significantly changed from their natural state. They often have high amounts of added sugar, starch, oil, and fat to make them more palatable. UPFs also tend to have artificial flavors, colors, and preservatives to extend their shelf life. Common examples of UPFs include fast food, salty snacks, cookies, cakes, frozen meals, and soft drinks.

Research shows that eating a diet high in UPFs is associated with greater odds of constipation than eating mostly unprocessed or minimally processed foods.

The reason may be that UPFs typically contain less fiber than their minimally processed counterparts.

One study found that the more UPFs you eat, the less fiber you’re likely to get in a day.

 And getting enough fiber every day is crucial for keeping stool moving through your digestive system to prevent constipation.

What to Eat Instead Cooking meals from scratch whenever possible and prioritizing whole foods like fruits, vegetables, and whole-grain products can help you stay on top of fiber intake.

Check ingredient lists to make sure food manufacturers have included minimal additives or preservatives and have placed natural ingredients at the top of the list.

5. Legumes

Legumes, including beans and lentils, have a reputation for fueling flatuence and bloating. Their high-fiber content may be tough to digest, especially if you suddenly boost your legume intake.

Plus, legumes contain raffinose family ogliosaccharides (RFOs), a type of carbohydrates that are difficult to digest. When your gut bacteria break down RFOs, they produce excess gases that build up and cause stomach pain and flatulence.

People with digestive conditions like irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD) tend to struggle more with foods that contain high amounts of RFOs, such as legumes, than those without digestive conditions.

What to Eat Instead Avoid or limit legumes with higher amounts of RFOs if you have irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD). These legumes include baked beans, chickpeas, lentils, and soybeans.

If you don’t have a digestive condition but are bothered by gas and stomach pain after eating legumes, try soaking them overnight before cooking. Research shows that soaking beans for at least 16 hours reduces the amount of RFOs and can help cut down on gas.

6. Caffeinated Foods and Drinks

Caffeine, an energy-boosting compound in coffee and tea, can stimulate gastrointestinal motility (the movement of food through the digestive tract), making contents move more quickly through your system.

 This faster movement can cause diarrhea, especially if you drink more than two or three cups of coffee or tea daily.

Thanks to its effects on motility, caffeine is also a common trigger for IBS symptoms like stomach pain and diarrhea.

Research shows that high levels of caffeine consumption are closed linked to more severe IBS symptoms, especially for females and people with overweight or obesity.

What to Eat Instead If caffeine upsets your stomach or causes IBS symptoms, try caffeine-free versions of your favorite beverages or search for caffeine alternatives. Dr. Lara recommends protein shakes with a higher dose of amino acids for an energy boost that may replace caffeine.

Illustrative graphic titled Best & Worst Foods for Digestion [[top section with green check]] Nuts and seeds Bananas Buckwheat Cooked vegetables Fish [[bottom section with red x]] Dairy products Fried foods Raw broccoli Beans Spicy foods. Everyday Health
Everyday Health

7. Spicy Foods

If you’re prone to diarrhea, indigestion, and other digestive issues, spicy foods may worsen symptoms. This is due to the effects of capsaicin, a compound that tricks your taste buds into thinking your body temperature has risen.

That tingling and burning feeling you experience around your mouth when you eat spicy foods passes through your digestive system, causing a temporary increase in metabolic rate (the amount of energy your body uses to function) that can trigger belly pain and cramps. The spiciness also quickens digestion, which may lead to diarrhea. It can even set off pain receptors in your colon, making bowel movements painful.

What to Eat Instead Lessening the effects of spicy foods is more a matter of adjusting flavor than cutting whole foods. Consider using milder herbs and spices like ginger, basil, rosemary, mint, and thyme to flavor your meals.

8. Certain Fruits

While fruits are generally an important component of a healthy diet, certain fruits can cause issues for people with digestive conditions.

All fruits contain fructose, a sugar that can be difficult to digest for people with IBS and other GI disorders.

 Dried fruits, apples, and pears have higher fructose levels than other fruits, which can cause lactose intolerance-like effects in people with IBS.

Fruit juice, watermelons, and stone fruits like peaches also contain a lot of fructose.

What to Eat Instead Fruits like bananas, blueberries, cantaloupes, grapes, oranges, and strawberries are lower in fructose and may be less likely to cause IBS symptoms.

9. Wheat, Rye, and Certain Other Grains

Some people experience digestive issues after eating grains containing gluten (a protein in wheat, rye, barley, and triticale).

In people with an autoimmune disorder known as celiac disease, for example, eating gluten causes damage to the small intestine.

The symptoms of celiac disease vary and may include bloating, constipation, gas, abdominal pain, or diarrhea.

Meanwhile, people with gluten intolerance (also known as nonceliac gluten sensitivity) experience abdominal pain, bloating or gas, fatigue, diarrhea or constipation, headache, nausea and vomiting, and other symptoms after consuming gluten.

The cause of these symptoms is unclear. People may actually be sensitive to a carbohydrate present in wheat rather than gluten that the gut doesn’t absorb fully. This means the carb sits in the gut, fermenting, which can lead to gas and other symptoms. Alternatively, wheat may irritate the stomach lining of those with gluten sensitivity.

What to Eat Instead Opt for gluten-free alternatives to popular foods like bread, pasta, crackers, and flour. Look for “gluten-free” on the label or check the ingredient list. Grains and starches that don’t contain gluten include amaranth, buckwheat, corn and cornmeal, flax, millet, and gluten-free flours such as rice, soy, corn, potato, and bean.

10. Soda

Many sodas contain high-fructose corn syrup, a refined sweetener that doesn’t absorb well in the gut and can worsen IBS symptoms like gas and bloating.

In addition, carbonated beverages like soda contain carbon dioxide, causing gas and bloating in some people.

Other soda products boast “zero calories” on the packaging but contain artificial sweeteners like aspartame and sucralose, which can trigger gas, bloating, and diarrhea.

Many sodas also contain caffeine and may cause loose stools or diarrhea.

What to Drink Instead Instead of soda, try sparkling water or seltzer for a bubbly beverage. However, some sparkling waters and seltzers still contain sugar, so be sure to check the nutrition label.

If the bubbles cause digestive issues, stick to flat water flavored with lemon, mint, or basil.

11. Alcohol

Alcohol can cause many digestive issues, especially if you have more than one or two drinks per day.

Diarrhea is one common symptom of drinking too much alcohol. Alcohol draws water into the gut, which can have a laxative effect. In addition, alcohol can irritate the intestine and speed up digestion.

Alcohol also quickens muscle contractions in the digestive system, leading to belly cramps and an urge to poop.

Bloating may also occur. Alcohol — particularly beer — disrupts the balance of bacteria in the gut, which increases gas production and makes your abdomen bloat.

What to Drink Instead Nonalcoholic beers, wines, and spirits are commercially available for those who enjoy the taste and social aspect of alcohol but not its gut effects.

When to Speak to a Doctor

Everyone’s gut works differently, and your awareness of your own digestive responses may give you some clues as to when you should seek help, says Kelci McHugh, RD, a North Carolina-based registered dietitian and assistant director of nutritional sciences at Ayble Health, a virtual gut health platform. “Consider speaking with your doctor when gut symptoms get in the way of your daily routine, you experience unintended weight loss, or show signs of health changes,” McHugh recommends.

The following digestive symptoms may also warrant a trip to the doctor:

  • Sudden or severe abdominal pain
  • Ongoing diarrhea
  • Fewer than three bowel movements a week most weeks
  • Heartburn more than two times per week
  • Unusually gassy or bloated
  • Blood in your stool
Note whether eating certain foods consistently gives you digestive symptoms. Your doctor may ask about digestive symptoms, recommend lifestyle changes, and discuss future diagnostic tests like a colonoscopy.

The Takeaway

  • The foods you eat can create digestive issues like abdominal pain, gas, bloating, nausea, heartburn, diarrhea, and constipation.
  • Certain foods are more likely to cause digestive issues than others, including dairy, cruciferous vegetables, high-fat foods, gluten, legumes, and more.
  • Consult your doctor if digestive symptoms become consistent or interfere with daily life.

Yuying Luo, MD

Medical Reviewer

Yuying Luo, MD, is an assistant professor of medicine at Mount Sinai West and Morningside in New York City. She aims to deliver evidence-based, patient-centered, and holistic care for her patients.

Her clinical and research focus includes patients with disorders of gut-brain interaction such as irritable bowel syndrome and functional dyspepsia; patients with lower gastrointestinal motility (constipation) disorders and defecatory and anorectal disorders (such as dyssynergic defecation); and women’s gastrointestinal health.

She graduated from Harvard with a bachelor's degree in molecular and cellular biology and received her MD from the NYU Grossman School of Medicine. She completed her residency in internal medicine at the Icahn School of Medicine at Mount Sinai, where she was also chief resident. She completed her gastroenterology fellowship at Mount Sinai Hospital and was also chief fellow.

Adam Felman

Author
Adam is a freelance writer and editor based in Sussex, England. He loves creating content that helps people and animals feel better. His credits include Medical News Today, Greatist, ZOE, MyLifeforce, and Rover, and he also spent a stint as senior updates editor for Screen Rant.

As a hearing aid user and hearing loss advocate, Adam greatly values content that illuminates invisible disabilities. (He's also a music producer and loves the opportunity to explore the junction at which hearing loss and music collide head-on.)

In his spare time, Adam enjoys running along Worthing seafront, hanging out with his rescue dog, Maggie, and performing loop artistry for disgruntled-looking rooms of 10 people or less.

EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
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