Fruit Juice, Soda Often Source of Gas
Breath Test Shows Fruit Sugar Upsets Many People
Oct. 21, 2002 -- If there's a rumbling in your belly, the culprit may be that soda you drank an hour ago. Lots of otherwise healthy people have trouble digesting fruit sugar, a study suggests.
A report at this week's meeting of the American College of Gastroenterology finds that nearly half of normal people get gas from fructose. This common fruit sugar is found in fruit juice and is used as a sweetener in some soft drinks.
There are about 25 grams of fructose in a 12-ounce can of soda. The average American eats or drinks 37 grams of fructose each day -- and many take in more than 60 grams a day. University of Kansas researcher Peter Beyer, RD, gave 15 healthy people a 25-gram dose of fructose. He then used a breath test to measure how much gas they gave off.
"When given levels of fructose commonly consumed in the Western diet, [breath analysis of] a significant number of our subjects showed hydrogen in excess of [normal levels] ... and they had symptoms like gas and diarrhea," Beyer says in a press release.
To be digested, fructose must be broken down before it gets to the colon (large intestine). When this doesn't happen, it becomes high-octane fuel for bacteria that normally live peacefully in the gut. The result of this feeding frenzy is hydrogen gas -- and symptoms of bloating, rumbling, pain, and loose stools.
Beyer suggests that people with these symptoms should get breath tests to see if fructose is the root cause of the problem. Such tests, he argues, should be made part of the standard gastroenterological exam.
The technical name for not being able to digest fruit sugar well is fructose malabsorption. Some people suffer from a much more serious problem called fructose intolerance. This sometimes-fatal condition is caused by a hereditary inability to digest fructose. People with fructose intolerance can suffer permanent liver damage from eating fructose. -->