If you’re undergoing radiation treatment for prostate cancer, here’s how you should change your diet to ensure that both diet and medical treatment work most effectively.

During Radiation Treatement: What to Eat and Why

“Depending on the type of radiation and technique used, some radiation treatments to the pelvis/prostate can often lead to urinary dysfunction and/or diarrhea,” says Crystal Langlois, RD, LD, Director of Nutrition, Cancer Treatment Centers of America at Southeastern Regional Medical Center.

“Proper hydration, particularly with water, and limiting foods or beverages with caffeine can be effective,” continues Langlois.

“It may be beneficial for patients to maintain adequate hydration during the day while decreasing fluid intake at night to reduce frequency of getting up to use the restroom at night.”


“Dietary management to help minimize diarrhea may require restricting milk products or purchasing low lactose products.

“Following a low residue diet can also be helpful to decrease frequency of bowel movements.

“A low residue diet includes avoiding greasy fatty fried foods, restricting fiber intake — particularly whole grains, nuts, corn and legumes.

“If watery diarrhea persists, adding soluble fiber such as applesauce or psyllium products can help to bulk your stool.

“Choosing canned fruits/veggies in place of fresh or frozen are also beneficial to decrease frequency of bowel movements.

If diarrhea becomes severe, electrolyte imbalances can occur. It may be beneficial to add clear juice, broth or electrolyte replacement drinks to your diet and consult your physician if medication or pharmacologic intervention needed.”

Not Experiencing Diarrhea?

During prostate cancer treatment or any cancer treatment for that matter, healthy diet is crucial to aid in recovery.

For those not suffering from diarrhea induced by radiation, fresh produce should be part of the dietary plan.

Furthermore, the diet you should have during prostate cancer treatment (save for special considerations to manage diarrhea) is the same diet anyone should have to lower the risk of cancer and other disease.

• Plant based – fresh produce as the main course and meats on the side

• Emphasis on foods in their natural state (e.g., an apple rather than bottled apple juice)

• High in fiber (unless, again, you’re struggling with diarrhea)

• Inclusion of fish

• Whole grains instead of processed

• Minimal intake of added sugars, if at all

• Poultry and beef in whole natural form rather than processed

• Grass-fed beef rather than grain-fed

• Beans, nuts, raisins and fruit for snacks rather than candy, cookies, chips or other munchies

For additional information on how to eat your healthiest during prostate cancer treatment, contact Cancer Treatment Centers of America at (855) 993-3381. 

Crystal Langlois

Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  
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