We all know that fiber — and even more fiber — is beneficial. Scientists are now studying if fiber can help cancer treatments be more effective.

A clinical trial is underway at the University of Texas MD Anderson Cancer Center in Houston to see if giving patients a fiber-rich diet of fruits, vegetables, beans, nuts and whole grains to nourish the microbiome might improve the odds that a cancer treatment of immunotherapy is effective. It turns out that some cancer patients respond to immunotherapy, and some don't. Scientists have found that patients who harbor certain gut bacteria have better responses to immunotherapy than patients who lack them.

Jennifer McQuade, an assistant professor and physician scientist in melanoma medical oncology at MD Anderson and her colleague Jennifer Wargo, a cancer surgeon, are studying if patients' microbiomes can be changed by what patients eat.

Some of the gut microbes that appear to improve how patients respond to immunotherapy are known to thrive on fiber.

McQuade's team examined the diets of 128 melanoma patients and found that those who regularly ate large amounts of fiber from fruits, vegetables and other plant foods had better outcomes on immunotherapy than patients who ate the least amount of fiber. Their findings, published in Science in December, showed that every five-gram increase in daily fiber intake was associated with a 30% lower risk of death or cancer progression.

In the new study, patients are given daily meals that include as much as 50 grams of daily fiber from foods like beans, lentils, farro, brown rice, fruits, and vegetables — about twice the recommended amount of 25 to 30 grams of fiber a day. By comparison, the average American eats roughly 15 grams a day. (A control group will eat a healthy diet that follows guidelines from the American Cancer Society.)

The bottom line is even if a person doesn't have cancer, eating more fiber is beneficial. Additional fiber means a healthier microbiome and a host of other benefits, from lowering cholesterol to helping with weight loss.

Q and A

Q: Is it better to sweeten a drink with sugar or sweetener?

A: Researchers found that drinking sugar-sweetened beverages may increase the risk for inflammatory bowel disorders more than drinking artificially sweetened beverages or natural juices. In a study of more than 121,000 IBD-free participants who were IBD-free at the onset of the study, participants completed 24-hour diet recalls between 2009 and 2012 to determine beverage intake of sugar-sweetened, artificially sweetened and natural juices. After a 10-year follow-up those drinking sugar-sweetened beverages had a considerably greater risk of IBD compared to those who did not. The study was published in the July 2022 journal of Alimentary Pharmacology and Therapeutics.

RECIPE

Here's a smoky black-eyed pea soup that is full of flavor and offers 10 grams of fiber. It's from Hy-Vee's Seasons magazine and perfect for those cool days.

SMOKY BLACK-EYED PEA SOUP

Servings: 8

6 slices thick-sliced hickory-smoked slab bacon, chopped

2 cups chopped unpeeled sweet potatoes

1 cup sliced celery

1 medium yellow onion, chopped

1 tablespoon lite Creole or Cajun seasoning

1 teaspoon minced garlic

1/2 teaspoon smoked paprika

1/2 teaspoon black pepper

2 (32-ounce) containers 33% less sodium chicken broth

1 (14-16-ounce) split smoked ham shank

1 tablespoon apple cider vinegar

2 (15.5 ounce) cans black-eyed peas, drained and rinsed

4 cups lightly packed baby kale

Cook bacon in a 6-quart Dutch oven over medium heat for 5-6 minutes or until crisp, stirring frequently. Remove bacon; drain on paper towels. Reserve 2 tablespoons drippings in Dutch oven. Add sweet potatoes, celery, onion, Creole seasoning, garlic, smoked paprika and black pepper to bacon drippings in Dutch oven. Cook over medium heat for 10-12 minutes, stirring occasionally. Add chicken broth, ham shank and vinegar. Cover and simmer over medium-low heat for 40 minutes, stirring occasionally. Remove ham shank from soup. Remove meat from shank and discard skin and bones. Chop meat into bite-size pieces. Return meat to soup mixture. Stir in black-eyed peas and kale. Simmer uncovered for 12 to 15 minutes or until kale is tender. Top with cooked bacon before serving. Serves 8 (1 1/2 cups each).

Per serving: 368 calories; 27 grams protein; 38 grams carbohydrates; 12 grams fat (4 grams saturated); 50 milligrams cholesterol; 10 grams fiber; 9 grams sugar (0 grams added); 825 milligrams sodium.

Charlyn Fargo is a registered dietitian with SIU School of Medicine in Springfield, Illinois, and the current president of the Illinois Academy of Nutrition and Dietetics. For comments or questions, contact her at [email protected] or follow her on Twitter @NutritionRD. To find out more about Charlyn Fargo and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

Photo credit: Iñigo De la Maza at Unsplash