• Posted April 19, 2024

Dietary Changes May Beat Meds in Treating IBS

The right diet may be the best medicine for easing the painful symptoms of irritable bowel syndrome (IBS), new research shows.

In the study, two different eating plans beat standard medications in treating the debilitating symptoms of the gastrointestinal disease. One diet was low in “FODMAPs,” a group of sugars and carbohydrates found in dairy, wheat and certain fruits and vegetables, while the second was a low-carb regimen high in fiber but low in all other carbohydrates.

Published April 19 in the journal Lancet Gastroenterology and Hepatology, the findings suggest that patients should first try dietary changes before moving to drugs for relief.

IBS is one of the most common and stubborn conditions gastroenterologists treat. It affects roughly 6 percent of Americans, with women diagnosed more often than men. Its symptoms are hard to ignore and life-limiting: abdominal pain, bloating, diarrhea and constipation.

Treatments often include dietary changes or taking medications that can include laxatives and antidiarrheals; certain antidepressants; and other prescription medications such as linaclotide and lubiprostone -- both of which increase fluid in your gut and the movements of your intestines.

Research has found that a low-FODMAP diet -- which involves avoiding foods like wheat products, legumes, some nuts, certain sweeteners, most dairy products and many fruits and vegetables -- can reduce IBS symptoms in most people, Dr. William Chey, a gastroenterologist at Michigan Medicine, told the New York Times.

But the diet is hard to stick with because it's so restrictive and requires carefully reintroducing foods to identify which ones you can’t tolerate, he explained.

Some research also supports simpler dietary changes, such as eating more slowly; eating smaller and more frequent meals; and limiting coffee, tea, carbonated beverages, alcohol and fatty or spicy foods, study author Sanna Nybacka, a dietitian and postdoctoral researcher at the University of Gothenburg in Sweden, told the Times.

After noticing that some of their patients also found relief with a low-carbohydrate diet, Nybacka and colleagues decided to design a trial comparing several treatment options.

Conducted at a hospital clinic in Sweden, researchers followed 241 women and 53 men with moderate to severe IBS. The participants were randomly assigned to one of three treatment groups for four weeks.

In the medication group, researchers gave each participant one of eight IBS medications based on their main symptoms, Nybacka said. If their primary complaint was constipation, they were prescribed a laxative called sterculia; if their main symptom was diarrhea, they gave them an antidiarrheal called loperamide (Imodium).

A second group was given groceries and recipes so they could follow a low-FODMAP diet, which included foods like rice, potatoes, quinoa, wheat-free bread, lactose-free dairy products, fish, eggs, chicken, beef and various fruits and vegetables. Nybacka said they were also encouraged to eat slowly, have regular, small meals, and limit other foods and drinks that could trigger symptoms.

The last group received groceries and recipes to follow a low-carbohydrate, high-fat diet, which focused on foods like beef, pork, chicken, fish, eggs, cheese, yogurt, vegetables, nuts and berries.

After four weeks, 76 percent of those in the low-FODMAP group and 71 percent of those in the low-carbohydrate group reported significant reductions in their symptoms, while only 58 percent of those in the medication group reported improvements. Among participants who noticed improvements, those in the diet groups reported much greater symptom relief than those in the medication group, Nybacka added.

Nybacka said she was surprised that the low-carbohydrate diet worked essentially as well as the low-FODMAP diet.

After the four weeks, some participants continued taking the medications and following the dietary changes. At six months, those in the diet groups still had fewer symptoms than they did at the start of the trial, despite the fact that most of them did not stick as closely to the diets.

Chey said the study provided “real data” to support what many doctors have seen in their practices: “Diet therapy is at least as good and probably better” than medication.

But because the trial was conducted on a relatively small group of people at a single medical center in Sweden, the findings will need to be confirmed in larger and more diverse groups of people, he added.

Not only that, some IBS drugs may need more than four weeks to take full effect, Dr. Lin Chang, a gastroenterologist at UCLA Health, told the Times.

For some, a combination of diet and medication may work best, Chang added.

Still, the findings confirm that dietary changes can be an important option for treating IBS, Chey added.

People should talk with their doctors before adopting either diet, Nybacka said, because there was a small increase in blood cholesterol levels among folks in the low-carbohydrate group.

And both diets may not be appropriate for those who have or are at risk for an eating disorder, Chey noted.

But for everyone else, IBS symptoms might be managed simply “by eating differently,” Nybacka said.

More information

Johns Hopkins Medicine has more on irritable bowel syndrome.

SOURCES: Lancet Gastroenterology and Hepatology, April 18, 2024; New York Times