Before we get into the details, let’s be clear: these are just general guidelines based on expert sources and the latest research. Every person responds to chemotherapy differently, and there is no one-size-fits-all approach to nutrition during treatment.
The most important thing is making sure you’re getting enough calories and nutrients to maintain your strength. If something works for you—even if it’s not on the “recommended” list—then that’s what matters. You know your body best.
That being said, certain foods tend to cause more digestive issues, nausea, or inflammation during treatment, especially for people with pancreatic cancer. The pancreas plays a huge role in digestion, so some foods can be harder to tolerate than others. This guide outlines common culprits that may trigger discomfort and provides alternatives to help you feel your best.
1. High-Fat and Fried Foods
For many people undergoing chemotherapy, fatty foods can be difficult to digest. This is especially true if your pancreas isn’t producing enough digestive enzymes, which can lead to bloating, cramping, diarrhea, and greasy stools.
But here’s the tricky part—you still need fat for energy. The key is choosing the right kinds of fats in the right amounts.
What to Avoid:
• Fried foods like French fries, fried chicken, and onion rings
• Fatty cuts of meat (bacon, sausage, ribs, pork belly)
• Heavy cream, butter, and rich cheeses
• Greasy takeout and fast food
If your food isn’t digesting properly, you might notice floating, pale-colored stools that are greasy or difficult to flush. That’s a sign your body isn’t absorbing fat properly, which can lead to weight loss and vitamin deficiencies.
What to Eat Instead:
• Lean proteins like grilled chicken, turkey, and fish
• Small amounts of healthy fats (avocado, nut butter, olive oil)
• Low-fat dairy options like Greek yogurt and skim milk
• Lighter cooking methods like baking, steaming, or air frying
2. Spicy or Acidic Foods
Chemotherapy can make your digestive system extra sensitive. Spicy foods can trigger nausea, acid reflux, and mouth sores, while acidic foods can irritate an already inflamed stomach.
What to Avoid:
• Spicy seasonings like chili powder, cayenne, and hot sauce
• Raw garlic and onions, which can be harsh on the stomach
• Acidic foods like citrus fruits, tomatoes, vinegar, and pickles
What to Eat Instead:
• Mild herbs like basil, oregano, and parsley to add flavor
• Ginger and peppermint (which can actually help with nausea)
• Low-acid fruits like bananas, melons, and apples
If you love spice and it doesn’t bother you, then don’t feel like you have to cut it out completely. Just listen to your body and adjust as needed.
3. Raw or Undercooked Foods
Chemotherapy weakens the immune system, making it harder for your body to fight off infections. Raw or undercooked foods can carry bacteria and increase the risk of foodborne illness, so it’s best to be extra cautious.
What to Avoid:
• Raw seafood (sushi, sashimi, oysters, clams)
• Undercooked eggs (homemade mayonnaise, soft-boiled eggs)
• Unpasteurized dairy products (soft cheeses like feta, brie, blue cheese)
• Cold deli meats (unless they are reheated until steaming hot)
What to Eat Instead:
• Cooked seafood like grilled salmon or shrimp
• Pasteurized dairy products and hard cheeses
• Freshly cooked meats instead of pre-sliced cold cuts
Food safety is extra important during treatment, so always wash fruits and vegetables thoroughly and store food properly to avoid contamination.
4. High-Sugar and Refined Carbohydrates
If you’re dealing with pancreatic cancer and diabetes, managing blood sugar becomes even more important. High-sugar foods can spike glucose levels, drain energy, and increase inflammation.
What to Avoid:
• Sugary cereals, pastries, candy, and desserts
• White bread, white rice, and highly processed snack foods
• Sweetened drinks like soda, fruit juice, and energy drinks
What to Eat Instead:
• Whole grains like quinoa, brown rice, and whole-wheat bread
• Natural sources of sweetness (berries, apples, pears)
• Hydrating drinks like herbal teas and diluted fruit-infused water
If you’re struggling with weight loss, your doctor may encourage you to eat more carbs—so again, it comes down to what works for you.
5. Gas-Producing and High-Fiber Foods
Some high-fiber foods can be too harsh on the digestive system, causing bloating, cramping, or diarrhea. While fiber is important, too much at once can be hard to handle during chemotherapy.
What to Avoid:
• Cruciferous vegetables (broccoli, cabbage, Brussels sprouts, cauliflower)
• Beans and lentils, which can cause gas
• Whole grains in large amounts
What to Eat Instead:
• Cooked vegetables like zucchini, carrots, and spinach (easier to digest than raw)
• Peeled fruits like apples, pears, and peaches
• Lighter grain options like oatmeal or white rice
Some people can tolerate fiber just fine, while others find it aggravates digestive issues. Pay attention to your own body and adjust accordingly.
6. Caffeine and Carbonated Beverages
Caffeine can cause dehydration, while carbonated drinks can worsen bloating and nausea. If you’re already struggling with stomach discomfort, these beverages might not be your best friend.
What to Avoid:
• Coffee, strong black tea, and energy drinks
• Soda, sparkling water, and fizzy drinks
What to Drink Instead:
• Decaf herbal teas like chamomile, ginger, or peppermint
• Plain water, coconut water, or electrolyte drinks
That being said—if you love your morning coffee and it doesn’t bother you, you don’t have to give it up. Just keep an eye on how you feel.
Additional Tips for Managing Nutrition
Changing your diet during chemotherapy isn’t about strict rules—it’s about finding what works for your bodyand making small adjustments to feel better.
1. Eat Small, Frequent Meals
Large meals can feel overwhelming, especially if you’re nauseous. Instead, try eating 5-6 small meals throughout the day with protein-rich options like eggs, tofu, or Greek yogurt.
2. Stay Hydrated
Even mild dehydration can worsen fatigue and nausea. Sip water throughout the day, and if plain water is unappealing, try broth, herbal teas, or diluted fruit juice.
3. Consider Enzyme Supplements
If you’re having trouble digesting fats, talk to your doctor about pancreatic enzyme replacement therapy (PERT), which can help break down food more effectively.
4. Work with a Dietitian
Everyone’s needs are different. A registered dietitian who specializes in oncology can help you create a meal plan that works best for you.
Cachexia
Cancer cachexia is a type of tumor-induced weight loss that can make it harder for your body to hold on to muscle and energy, even if you are eating regularly. It speeds up calorie burning, breaks down muscle, and can make you feel less hungry, which can lead to rapid weight loss. This isn’t just about eating more, it’s a complex issue that affects how your body processes food. Finding ways to get enough protein, healthy fats, and nutrient-rich foods can help slow muscle loss and keep your strength up.

If you are struggling with loss of appetite or ongoing weight loss, talk to your doctor. There are medications that can help stimulate your appetite and make it easier to get the nutrition your body needs. Working with a dietitian and making small, frequent meals part of your routine can also help you feel stronger and more in control.
Final Thoughts
At the end of the day, your number one goal is to keep your weight up and stay strong for treatment. If something on this list works for you, keep eating it. If something recommended doesn’t sit well, skip it.
Pancreatic cancer is hard enough without overthinking every bite. Do your best, listen to your body, and get support when you need it. PANCAN recommends everyone starting pancreatic enzymes and speaking to a registered dietitian. Your diet might have not been the most important issue in your plate before, but prioritizing it early can help with the severity of some unpleasant side effects of chemo.
If this guide helped you, share it with someone who might need it. And as always, talk to your healthcare team before making any big dietary changes.
Reference List 📚
- Let’s Win PC. “What to Eat—and What to Avoid—When You Have Pancreatic Cancer.” Let’s Win PC.
- Johns Hopkins Medicine. “Cancer Diet: Foods to Add and Avoid During Cancer Treatment.” Johns Hopkins Medicine.
- UCLA Health. “Pancreatic Cancer Diet: How to Eat for Your Symptoms.” UCLA Health.
- City of Hope. “Foods to Avoid While Undergoing Cancer Treatment.” City of Hope.
- Pancreatic Cancer Canada. “Diet and Nutrition.” Pancreatic Cancer Canada.
- MD Anderson Cancer Center. “10 Things to Avoid While Receiving Chemotherapy.” MD Anderson Cancer Center.
- Sunnybrook Health Sciences Centre. “Pancreatic Cancer and Diabetes: What You Need to Know.”
- Pancreatic Cancer Canada. “Diet and Nutrition Guidelines.” Pancreatic Cancer Canada.
- Thomas Jefferson University. “Pancreatic Cancer Diet Guide.” Jefferson University.