By now, you’ve likely heard of glucagon-like peptide-1 (GLP-1) agonists — commonly called GLP-1 drugs. These medications were originally created to treat type 2 diabetes. Today, they’re also widely used to support weight management in people living with obesity.

Like most medications, GLP-1 drugs can cause side effects. If you’re currently taking GLP-1 drugs as a treatment for obesity, you may already be aware of this. What you might not know is that there are specific foods that may be triggering your side effects.

This article explains how GLP-1 drugs affect your digestive system and how avoiding certain foods may help ease nausea, bloating, and other uncomfortable symptoms.

GLP-1 Drugs and Digestion

GLP-1 medications help regulate blood glucose (sugar) levels. They do this by mimicking the GLP-1 hormone that’s naturally produced by the small intestine. After you eat, the GLP-1 hormone helps manage digestion and blood sugar by:

• Telling your pancreas to release insulin, which lowers glucose levels in the blood
• Stopping extra glucose from entering the blood by blocking glucagon, a hormone that increases blood sugar
• Communicating to your brain that you’re full
• Slowing down gastric emptying (the time it takes your stomach to empty), which reduces how much glucose enters your bloodstream at once

GLP-1 receptor agonists work by taking on the roles of the natural GLP-1 hormone. Because they help you feel full longer and reduce your appetite, many people take GLP-1 drugs to eat less and lose weight.

Side Effects of GLP-1 Drugs

GLP-1 drugs help to slow digestion, which aids in controlling blood sugar levels. But when your stomach empties more slowly, some foods — especially those that are harder to digest — may lead to uncomfortable symptoms.

The most common side effects of GLP-1 drugs are gastrointestinal (digestive). These side effects affect between 40 percent and 85 percent of people taking these medications and may include:

• Nausea (sometimes with vomiting)
• Constipation or diarrhea
• Acid reflux (heartburn)
• Upset stomach
• Bloating
• Lower appetite

Nausea is the most commonly reported side effect, especially during the first few weeks after starting a GLP-1 medication.

In rare cases, GLP-1 drugs have been linked to more serious gastrointestinal side effects, including pancreatitis (inflammation of the pancreas) and bowel obstruction (a blockage in the intestine). If you experience severe or persistent symptoms, talk to your healthcare provider right away.

Foods To Avoid on GLP-1 Drugs

If you’re taking a GLP-1 drug, you may need to be more mindful of what you eat to help reduce side effects. Certain types of food are more likely to trigger symptoms like nausea, bloating, or heartburn, especially as your stomach empties more slowly.

Foods that may increase the risk of side effects include:

• High-fat, greasy, or fried foods, such as fried chicken, bacon, sausages, and cheeseburgers
• Processed foods, such as potato chips, packaged cookies, and other ultra-processed items
• Spicy foods, including hot peppers, chili, and heavily seasoned dishes
• Sugary foods and drinks, like soda, candy, cake, and sweetened coffee drinks
• Refined carbohydrates, such as white bread, pasta made with white flour, and sugary breakfast cereals
• Foods with a high glycemic index, such as white potatoes and some instant rice products

GLP-1 drugs slow down how quickly food leaves your stomach. This process is called delayed gastric emptying. When greasy or high-fat foods linger in the stomach, they can increase the chances of nausea, acid reflux, and bloating. At the same time, eating too little fiber may lead to constipation or diarrhea.

5 Tips for Managing GLP-1 Side Effects

If you’re taking a GLP-1 medication and experiencing side effects, there are steps you can take that may help you feel better. These tips can help reduce digestive symptoms like nausea, bloating, and constipation.

1. Eat a Balanced, Gentle Diet

Eating a balanced diet of nutrient-rich, easy-to-digest foods can help prevent unpleasant symptoms. Some of the best foods to focus on include:

• Lean proteins like chicken, fish, tofu, or eggs
• Whole grains such as oats, quinoa, and brown rice
• Fruits and vegetables, especially cooked or peeled varieties, for easier digestion

Choose low-fat, “bland” foods, and bake, boil, or grill your meals to keep fat content low. Make sure to get enough protein, as it helps regulate blood sugar, supports muscle health, and keeps you feeling full longer.

Fiber is key to preventing constipation, but introduce it gradually. A sudden increase can cause gas or diarrhea. If you’re already experiencing diarrhea, your doctor may suggest cutting back on high-fiber foods temporarily.

2. Eat Smaller Meals More Often

Reducing your portion size is another easy way to help reduce symptoms like nausea and bloating. Instead of three large meals, try several small meals throughout the day. Eat slowly and without distractions to give your body time to register fullness.

Listen to your hunger and fullness cues — stop eating when you feel satisfied, and aim to eat only when you’re truly hungry.

3. Time Your Meals Carefully

The timing of your meals can affect how you feel. To reduce the risk of stomach upset:

• Avoid eating right before bed or lying down after a meal.
• Give your body time to digest by staying upright for at least an hour after eating.
• Avoid intense activity immediately after meals. Gentle movement or rest is best.

4. Stay Hydrated, the Right Way

Drinking enough fluids is important, especially if you’re dealing with diarrhea or reduced appetite. Sip clear, hydrating drinks like water or broth throughout the day.

Some tips for easier hydration include:

• Taking small sips to avoid feeling too full
• Skipping the straw, as it can cause you to swallow air, which may worsen bloating
• Choosing water-rich foods like soups or yogurt (though avoid dairy products in general if they worsen your symptoms)

Some drinks may trigger side effects. Your doctor may suggest limiting or avoiding:

• Alcohol
• Caffeinated drinks (like coffee or energy drinks)
• Sugary or artificially sweetened drinks (like soda or some sports drinks)

If you’re struggling to eat enough, meal replacement shakes may help you get the nutrients you need.

5. Talk With a Registered Dietitian

In addition to your doctor, a registered dietitian can help you create a food plan tailored to your needs. They can guide you in choosing foods that support your health, meet your nutrition goals, and minimize side effects from GLP-1 drugs.

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Are you taking a GLP-1 drug? Have you noticed side effects caused by eating specific foods? Share your thoughts in the comments below, or start a conversation by posting on your Activities page.