News / Health

Dietary Fiber May Prevent Asthma

A new study finds that soluble fiber, which comes from fruits and vegetables, may reduce inflammation in the lungs.
A new study finds that soluble fiber, which comes from fruits and vegetables, may reduce inflammation in the lungs.

Related Articles

Jessica Berman
Certain types of dietary fiber may be protective against asthma, a lung disease that until recently was largely unknown in the developing world.  Experts note the incidence of asthma is increasing in less developed countries, as people there shift their eating habits away from high-fiber foods in favor of processed ones.

We get two types of dietary fiber from food - insoluble and soluble. Insoluble fiber, from foods like whole grains, cucumbers and broccoli, includes so-called roughage, which helps cleanse the bowel.

A new study by researchers in Switzerland suggests that soluble fiber, which comes from fruits and vegetables, and is broken down by microbes in the intestines, may reduce inflammation in the lungs. 

Benjamin Marsland, an immunologist at the University of Lausanne, says that until recently, asthma was virtually unknown in nations where people eat a lot of soluble fiber.

“In some countries, Burkina Faso, for example, dietary fiber intake is very high and there is no development of allergies whereas in westernized countries we have an intake of dietary fiber is low and the allergies have been increasing,” Marsland said.

Gut bacteria break down soluble fiber, which includes pectin from apples, berries and citrus, into short chain fatty acids. Marsland says the fatty acids interact with spongy tissue inside the bones, where protective immune cells are produced, and help quiet immune system overactivity. An overzealous immune reaction can lead to inflammation.

To see whether dietary fiber could influence disease development outside the digestive tract, such as asthma, Marsland and colleagues studied two groups of rodents.  One group of mice had been fed a diet high in soluble fiber for two weeks while the other group was fed a diet low in pectin.

Both groups were then exposed to dust mites, a leading cause of asthma, a condition marked by lung inflammation, narrowing of the airways and wheezing.

Marsland says the mice that ate less soluble fiber had strong allergic reactions to the dust, including the presence of inflammatory compounds in the lungs and constricted airways similar to what’s seen in people.

The mice that consumed food rich in pectin, according to Marsland, had lower levels of the immune cells that are usually elevated in allergic asthma.

“So the mechanism through which diet is helping the lung is the dietary fiber changes the bacteria in our intestinal tract which changes the metabolites in our circulation and this is influencing how our immune cells develop,” he said.

Researchers confirmed their findings by injecting the mice with another short chain fatty acid.  Again, there were fewer inflammatory markers among rodents given the compound.

An article describing a link between soluble fiber and asthma is published in the journal Nature Medicine.

You May Like

US Investors Eye IPO for China's Alibaba

E-commerce giant handled 80 percent of China's online business last year, logging more Internet transactions than US-based Amazon.com and eBay combined More

Video Uneasy Calm Settles Over Israel, Gaza Strip

As cease-fire begins, Palestinians celebrate in streets; Israelis remain wary More

Video Chinese Doctors Use 3-D Spinal Implant

In treatment of a 12-year-old boy Chinese doctors used a 3-D printer and special software to create an exact replica of vertebra More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Chinese Doctors Use 3-D Spinal Implanti
X
August 27, 2014 4:53 PM
A Chinese boy suffering from a debilitating bone disease has become the first patient with a part of his spine created in a three-dimensional printer. Doctors say he will soon regain normal mobility. VOA’s George Putic reports.
Video

Video Chinese Doctors Use 3-D Spinal Implant

A Chinese boy suffering from a debilitating bone disease has become the first patient with a part of his spine created in a three-dimensional printer. Doctors say he will soon regain normal mobility. VOA’s George Putic reports.
Video

Video Uneasy Calm Settles Over Israel, Gaza Strip

Israel and the Gaza Strip have been calm since a cease-fire set in Tuesday evening, ending seven weeks of hostilities. Hamas, which controls Gaza, declared victory. Israelis were more wart. VOA’s Scott Bobb reports from Jerusalem.
Video

Video India’s Leprosy Battle Stymied by Continuing Stigma

Medical advancements in the treatment of leprosy have greatly diminished its impact around the world, largely eliminating the disease from most countries. India made great strides in combating leprosy, but still accounts for a majority of the world’s new cases each year, and the number of newly infected Indians is rising - more than 130,000 recorded last year. Doctors there say the problem has more to do with society than science. VOA News reports from Kolkata.
Video

Video Northern California Quake: No Way to Know When Next One Will Hit

A magnitude 6.0 earthquake rocked northern California’s Napa Valley on Sunday. Roads twisted and water mains burst. It was the wine country’s most severe quake in 15 years, and while hospitals treated many people, no one was killed. Arash Arabasadi has more from Washington on what the future may hold for those residents living on a fault line.
Video

Video Scientists Unlock Mystery of Bird Flocks

How can flocks of birds, schools of fish or herds of antelope suddenly change direction -- all the individuals adjusting their movement in concert, at seemingly the same time? British researchers now have some insights into this behavior, which has puzzled scientists for a long time. VOA's George Putic has more.
Video

Video Ukraine: Captured Troops Proof of Russian Role in Separatist Fight

Ukrainian officials say they have captured Russian soldiers on Ukrainian territory -- the latest accusation of Moscow's involvement in the conflict in eastern Ukraine. VOA's Gabe Joselow reports from the Ukrainian side of the battle, where soldiers are convinced of Russia's role.
Video

Video Rubber May Soon Come From Dandelions

Synthetic rubber has been around for more than a century, but quality tires for cars, trucks and aircraft still need up to 40 percent or more natural rubber content. As the source of natural rubber, the rubber tree, is prone to disease and can be affected by bad weather. So scientists are looking for replacements. And as VOA’s George Putic reports, they may have found one in a ubiquitous weed.
Video

Video Jewish Life in Argentina Reflected in Yiddish Tango

Jewish people from across Europe and Russia have been immigrating to Argentina for hundreds of years. They brought with them dance music that were eventually mixed with Argentine tango. The result is Yiddish tango -- a fusion of melodies and cultural experiences that is still evolving today. Elizabeth Lee reports from the Skirball Cultural Center in Los Angeles, where one band is bringing Yiddish tango to an American audience.

AppleAndroid