When you have cancer, being mindful of what you eat and drink becomes even more important. Your body is working hard to fight disease and heal, burning more calories than usual, even at rest and treatment can also change how food tastes and how your body digests it. While there is no official bladder cancer diet, a balanced one may support recovery and ease side effects like fatigue, constipation, and nausea.
The Importance of Nutrition During and After Bladder Cancer Treatment
Adequate nutrition is vital for individuals during and after cancer treatment. It helps provide essential nutrients the body needs, helps maintain strength, and reduces the side effects of cancer treatment. A nutritious, balanced diet helps reduce the risk of many cancers.
General Dietary Recommendations
Doctors do not recommend one specific diet to treat or help prevent bladder cancer. However, evidence suggests certain dietary patterns may help lower the risk of bladder cancer and other cancers. The American Cancer Society (ACS) recommends following a “healthy eating pattern” at all ages.
A healthy eating pattern may include the following foods:
Fruits
Fruits supply the body with important vitamins, minerals, and antioxidants during cancer treatment. People should generally aim for around 1.5 to 2 cups of fruit each day. Fruits high in fiber, such as apples and berries, can promote bowel regularity if someone is experiencing constipation. Low fiber fruits, such as bananas, could be helpful for those experiencing diarrhea. Some studies suggest the following fruits may help reduce the risk of developing bladder cancer: apples, cactus pears, pomegranates, cranberries, and citrus fruits. However, researchers need to conduct further studies to confirm their findings.
Read also: Diet After Gallbladder Surgery
Vegetables
As well as containing a variety of vitamins and minerals, some vegetables are rich in antioxidants. A 2021 study found an association between higher intakes of total and non-starchy vegetables and a reduced risk of bladder cancer among females. Common non-starchy vegetables include artichoke, asparagus, baby corn, beetroot, Brussels sprouts, broccoli, cabbage, carrot, cauliflower, cucumber, eggplant, greens, leek, mushroom, onion, pepper, radish, salad greens, squash, and tomato.
Whole Grains
Whole grains have more nutrients and fiber than refined grains because they include all parts of the kernel that manufacturers discard during the processing of refined grains. A 2020 study concluded that higher intakes of whole grains and dietary fiber, individually and in combination, may reduce the risk of bladder cancer. Examples of whole grains include barley, bulgur, millet, quinoa, brown rice, red rice, wild rice, oatmeal, popcorn, whole wheat flour, whole grain breakfast cereals, and whole wheat bread, pasta, and crackers. At least half of the grains people consume should be whole grains.
Protein Sources
Protein is an essential dietary element to help the body grow and repair and keep the muscles and bones functional. Consuming enough protein is crucial during cancer treatment for healing, energy levels, and fighting infection. Additionally, consuming enough protein during cancer treatment is crucial when experiencing appetite loss and nausea. Sources high in protein include milk products, eggs, meats, poultry, fish, beans, legumes, nuts, and seeds. People should eat around 0.8 grams (g) of protein per kilogram (kg) of body weight daily. The ACS recommends selecting protein foods such as fish, poultry, and beans more frequently than red meat. Aim for 20 to 30 grams per meal or snack. Try soups with chicken, tempeh, or mashed beans. Fish and skinless chicken are easy to digest. If you eat red meat, choose lean cuts like flank steak. When your appetite is low, soft or liquid proteins may be easier to eat. Scrambled eggs, smoothies with Greek yogurt or nut butter, and ready-made protein drinks are all good choices.
Beneficial Fats
The body needs fat to function. It uses fat, protein, and carbohydrates for energy as calories and stores extra calories to maintain skin and hair and insulate the body. Plant foods such as nuts, avocados, and olive and canola oils contain monosaturated fats. Polyunsaturated fats are in animal and plant foods such as nuts, seeds, salmon, and vegetable oils. One large 2022 study suggested that a higher intake of monounsaturated fats and plant-based oils may lower the risk of bladder cancer in females.
Water
The ACS states that some evidence shows drinking plenty of fluids could lower a person’s risk of bladder cancer. Individuals who drink enough daily fluids, particularly water, typically have lower rates of bladder cancer. This may result from them emptying their bladders more often, helping prevent chemicals from remaining in the bladder for prolonged periods. Aim for about eight or so cups a day, or at least half your body weight in ounces. Plain water is great, but it might not be enough on its own. That’s because your cells absorb water better when it includes a bit of sugar and sodium. Your doctor might suggest an oral rehydration beverage. Juice with a pinch of salt also works.
Read also: Diet and Bladder Stones
Foods to Limit or Avoid
The ACS advises that a healthy eating pattern limits or avoids the following: red meats, processed meats, sugar-sweetened beverages, processed foods, refined grains, and alcohol. Research from 2018 found an association between Western dietary patterns and a higher risk of bladder cancer recurrence. A Western diet is high in fat, animal meat, processed products, and foods with added sugars.
Specific Dietary Strategies
The Mediterranean Diet
A 2022 review of studies found the Mediterranean diet to have a protective effect against bladder cancer. Researchers stated that following this diet may reduce a person’s risk of developing bladder cancer, but more studies are needed to confirm this. This means eating more plant-based foods and less sugar, salt, and saturated fat. Fruits, vegetables, and whole grains - plus beans, nuts, and olive oil - are the way to go. Fish and chicken are also options. The Mediterranean diet is a good starting point. Use it as a guide to make small changes, like swapping butter for olive oil or using beans instead of beef in soup. You can make bigger changes as time goes on.
Fiber Intake
It helps with both constipation and diarrhea, two common side effects of bladder cancer treatment. You’ll find fiber in plant foods like fruits, vegetables, and whole grains. Try adding chia seeds or flax to yogurt. You can also toss veggies into pasta and stir beans or lentils into soups. Drink plenty of fluids to help food move smoothly through your system. If your stomach’s sensitive, try soluble fiber from soft foods like oats, bananas, and cooked veggies like carrots.
Managing Treatment Side Effects Through Diet
Most people who undergo treatment for bladder cancer have side effects that make it difficult to eat and maintain nutrition.
- Dysgeusia (Distorted Sense of Taste): Dysgeusia is a common side effect of chemotherapy, a condition that distorts a person’s sense of taste. Some people report that foods taste metallic, sour, bitter, or sweet. Others say that all foods taste the same. Tell your care team about your symptoms. Choose cold or room-temperature foods. Experiment with different cooking techniques. If things taste metallic, add lemon, lime, herbs, or a splash of vinegar to boost flavor. Use plastic utensils if things taste metallic.
- Loss of Appetite: If you are not feeling hungry, food may be the last thing on your mind. Eat small amounts more frequently. Schedule mealtimes. Eat when you’re hungry. Take advantage of the times when you feel your best. If ice cream is all you can manage, that still counts. What matters most is getting enough, not following the perfect plan.
- Nausea: Eating small meals throughout the day when you have an appetite is really important to make sure you avoid overeating when you get too hungry. Avoid smells that make you sick.
- Constipation and Diarrhea: Dealing with both diarrhea and constipation requires short-term adjustments to your diet. For diarrhea, opt for low-fiber food such as white bread rather than wheat bread, and avoid fibrous or leafy vegetables. If you’re dealing with constipation, boost your fiber intake.
- Dehydration: It’s very important to keep your liquid intake up by drinking at least eight cups of fluids a day, or more if possible! Tracking your intake of water can also help ensure you are meeting this goal.
Foods to Consider
- Antioxidant-Rich Fruits and Vegetables: Colorful fruits and vegetables like berries, citrus fruits, broccoli, kale, and carrots are rich in antioxidants, which are health-promoting plant components (such as vitamin C, beta-carotene, and flavonoids). These nutrients may help protect cells from damage and keep them healthy.
- Cruciferous Vegetables: Cruciferous vegetables, in particular, contain compounds like isothiocyanates, which are natural chemicals that may help protect cells from damage. Studies have found that eating cruciferous vegetables is associated with a lower risk of bladder cancer, and there’s ongoing research exploring the effects of these vegetables in people with bladder cancer. Cruciferous vegetables include broccoli, Brussels sprouts, cabbage, cauliflower, and kale.
- High-Fiber Whole Grains: Foods like oatmeal, quinoa, brown rice, and whole-grain bread provide essential fiber, which can help ease the side effects of bladder cancer treatments. Fiber helps maintain healthy digestion and prevents constipation, which is important if you’re undergoing treatments or taking medications that affect your digestive health.
- Lean Proteins: The following lean proteins are easier on the digestive system and provide protein to help you maintain muscle during treatment: Fish, such as salmon, Chicken, Eggs, Tofu, and Beans.
- Hydrating Beverages: Staying hydrated is important for keeping your bladder and urinary tract healthy. Drinking enough fluids helps dilute urine, flush out toxins, and minimize irritation to the bladder lining, which is particularly important during cancer treatment.
Common Myths About Diet and Cancer
- Myth: Sugar feeds cancer.
- Truth: All cells, including healthy tissue and cancer, use glucose (a type of sugar) for fuel. There’s no solid evidence that cutting added sugar will starve cancer or that eating it will make your cancer spread. However, overeating sugar can contribute to gaining weight or obesity, which are major risk factors for cancer.
- Myth: Artificial sweeteners cause bladder cancer.
- Truth: Research doesn’t support that. You can include them, especially if sugar substitutes help you enjoy food or stay hydrated. Just make sure you’re getting enough calories overall.
- Myth: A plant-based diet will cure cancer.
- Truth: Diet isn’t a treatment. But eating more plant foods can support recovery by giving your body fiber, antioxidants, and anti-inflammatory nutrients.
After Bladder Removal (Cystectomy)
If you’ve had your bladder removed (cystectomy), your body may handle food and fluids differently. You might need to drink more fluids with electrolytes (minerals like salt and potassium) and eat low-fiber, easier-to-digest foods. Your doctor might suggest boosting the amount of protein you eat, especially in the first four to six weeks after surgery.
Read also: Foods to Support Bladder Function
The Role of Supplements
According to research, there is little benefit from taking dietary supplements while having cancer treatment. Many individuals who eat a balanced, varied diet will likely get enough vitamins and minerals from that. Although there is evidence that a diet high in fruits, vegetables, and other plant-based foods may reduce cancer risk, there is inconsistent evidence about dietary supplements decreasing cancer risk. Some dietary supplements may interact with cancer therapies, such as chemotherapy and radiation therapy, and reduce their effectiveness. People with bladder cancer should only take dietary supplements on the advice of a doctor or dietitian. Both cancer and cancer treatment can contribute to deficiencies of certain nutrients, including vitamin D, folate, and vitamin B12. You can ask your doctor whether supplements are right for you.
Working with Healthcare Professionals
There’s no single “bladder cancer diet” that works for everyone because your cancer stage, treatment plan, and other health conditions all play a role. Working with your oncologist (a doctor who specializes in treating cancer) and a dietitian, you may discover that some foods and drinks can help improve your symptoms while living with bladder cancer. If eating still feels impossible, ask your doctor about seeing a dietitian. If your care team is concerned about your nutritional health, you may be referred to an oncology dietician.
Additional Tips
- Be mindful of what you eat and drink.
- Eat foods with plenty of fiber.
- Stay hydrated. Each person needs a different amount of water, so talk to your doctor about how much water you should be drinking every day.
- Without enough calories and protein, your body breaks down muscle for energy. This can slow recovery and make you tired.
- Start with small, soft meals or snacks: a banana smoothie with nut butter, scrambled eggs with avocado, or soup with blended beans.
- Use plastic utensils if things taste metallic.
- Some foods and drinks may bother your bladder or gut, especially during or after cancer treatment. Common triggers include spicy foods, citrus, alcohol, caffeine, fizzy drinks, and sometimes artificial sweeteners. But everyone reacts differently. What bothers one person might be fine for you. Keep a food journal to track what helps and what makes things worse. Work with a dietitian if you're unsure what’s helping or hurting.