Dietary adjustments may relieve irritable bowel syndrome

Reversal of Fortune

If you’re one of the millions who suffer from irritable bowel syndrome (IBS) (which affects 40 million in the U.S. alone), you know all too well the uncomfortable symptoms: diarrhea, constipation, gas, and bloating.

To make matters worse, IBS can be triggered by a number of factors, including stress, hormonal changes associated withmenopause, and even the disruption of the brain
neurotransmitter serotonin that helps regulate the digestive
system. And because selective serotonin reuptake inhibitors
(SSRIs), such as Prozac, increase serotonin levels, SSRIs
are sometimes prescribed to treat IBS. Anti-gas and anti-
diarrheal medications are also prescribed, as well as acid
reflux drugs.

But before you sign on for an expensive round of drugs with
who-knows-what side effects, you need to know about a new study that confirms what we’ve known for a long time at HSI:
dietary adjustment is often the only treatment necessary
to relieve IBS.

Avoidance techniques

The next time you’re at the grocery store, pick out a few
products at random – cereal, soft drinks, crackers, etc. –
and look for “fructose” on the ingredients panel. More often
than not, you’ll find it there. Fructose was once embraced
as the healthy alternative to sugar, but the evidence now
suggests that fructose can be just as harmful as table
sugar. And it may also trigger irritable bowel syndrome.

As part of their ongoing fructose research, a team of
gastroenterologists at the University of Iowa (UI) recently
conducted a one-year study to determine if IBS symptoms
could be reduced with a fructose-restricted diet.

A group of 80 IBS patients were given a fructose intolerance
breath test. This test checks for the presence of gases in
the breath that are produced when fructose is not properly
absorbed in the digestive tract. Thirty subjects were found
to be fructose intolerant. Each member of this group was
given detailed information about dietary sources of fructose
and how to avoid them.

Over the course of the following year, four patients dropped
out of the study. When the remaining subjects were
interviewed to determine their level of IBS symptoms and
assess their compliance with the fructose-free diet, 54
percent had successfully remained on the diet. This group
showed a significant decline in IBS symptoms, and some
reported complete absence of abdominal pain.

All of the subjects who didn’t stick to the fructose-free
diet showed no improvement in their IBS symptoms.

Reporting these findings at the 68th Annual Meeting of the
American College of Gastroenterology earlier this month, the
IU researchers noted that their previous fructose research
indicated that perhaps more than half of all IBS patients
are fructose intolerant (particularly those with persistent
diarrhea). And many of these patients might easily reduce
their symptoms simply by avoiding fructose foods.

Absorption issues
Fructose intolerance could more accurately be described as
fructose malabsorption. If your body is unable to absorb
fructose during digestion, the fructose passes into the
colon where it’s consumed by bacteria. When bacteria digests fructose in the colon, acids and gases are produced that trigger IBS symptoms such as bloating, cramping and
diarrhea. Some of the gases pass into the bloodstream, and can then be detected in the breath, which is why the breath
test is an effective way to diagnose fructose intolerance.

But IBS patients who try to remove fructose from their diets
have their work cut out for them. Fructose is found
primarily in alcoholic beverages, corn, and corn-based
products. Unfortunately, derivatives like corn oil, corn
syrup, and fructose syrup are used in a wide variety of

In the e-Alert “Back to the Garden” (11/19/02) I told you
about a review of nutritional data from the Department of
Nutrition at the University of California, Davis, revealing
that America’s consumption of fructose rose more than 25
percent between 1970 and 1997; due primarily to its use in
processed foods.

In animal studies, the UC team found that fructose
consumption contributes to insulin resistance, an impaired
tolerance to glucose, high blood pressure, and elevated
levels of triglycerides. And although the data in humans is
not quite as conclusive as the animal trials, the
researchers report that an increased intake of fructose may
increase body weight and encourage insulin resistance, both of which are risk factors for type 2 diabetes.

If you have any of the symptoms of irritable bowel syndrome,
you certainly can’t go wrong by reducing your fructose
intake. Then ask your doctor about taking a fructose breath
test. If your doctor isn’t familiar with this test, you may
be able to find a physician who is by checking the web site
for the American College for the Advancement of Medicine

To Your Good Health,

Jenny Thompson
Health Sciences Institute

“ACG: Fructose Linked to Irritable Bowel Symptoms” Charlene Laino,, 10/17/03,
“Fructose Intolerance?”, 10/13/03,
“Gas, Bloating: Always Uncomfortable?” Jeanie Lerche Davis,
WebMD, 10/22/03,
“Fructose, Weight Gain, and the Insulin Resistance Syndrome”
American Journal of Clinical Nutrition, November 2002 Vol.
76, No. 5, 911-922,
“Fructose is Not an Acceptable Sugar” Dr. Joseph Mercola,, 11/13/02,