Or how raisins kicked my butt!

A woman holding fruits and diarrhea pills.

Most of the time fruits can be good for you, but not if you are chasing them with diarrhea pills.
© Can Stock Photo

Fructose malabsorption or fructose intolerance basically means that your body has problems digesting fructose. Fructose is the sugar in fruit and lots of other foods. It was one of the last pieces of the IBS puzzle for me and may be important for you.

Here’s what happened to me, is it happening to you?

I stopped eating all kinds of junk food and put together a good, healthy diet. I admit I used to have terrible eating habits. So I added all kinds of fruit, nuts and lean meat etc.

I added lots of fruits because I’ve never been good about eating vegetables. Besides fruit is supposed to be good for you, right?! And it usually is…

But my IBS symptoms started to get worse!

So back I went back to the food elimination diet .

And unbelievably the trouble turned out to be the large amounts of fruit (or fruit sugar) I was eating!

I could eat a banana and a couple of apples, but throw in a cup of raisins, and I felt like my guts were in a grinder!

My Gastroenterologist (the gut doctor ;) told me that fructose causes trouble for a lot of people. I wish he had mentioned it earlier :(.

It turns out that I can tolerate some fructose, but when I eat raisins or other high fructose foods (especially without anything else), I get very sick with IBS symptoms.

What’s the difference between fructose malabsorption and hereditary fructose intolerance?

Sign saying fructose intolerance

© Can Stock Photo

First of all, it really is fructose malabsorption with a P, not malabsorbtion with a B, even though the P just looks wrong to me.

Either way, the medical establishment changed the name to avoid confusion with a condition called “hereditary fructose intolerance” which is very similar to fructose malabsorption.

In both cases the body has trouble digesting fructose, which causes all the symptoms of IBS (except constipation).

The difference is that hereditary fructose intolerance is a genetic problem that runs in families.

Hereditary fructose intolerance causes all kinds of health problems for children including IBS symptoms, vomiting, jaundice, poor appetite, sleepiness and more. It affects about 1 in 10,000 people (so it’s pretty rare), and it’s there from birth.

Fructose malabsorption is MUCH more common. At least 30% of the population (3 out of 10 people) or even more, have some level of fructose malabsorption.

Also fructose malabsorption can develop over time and worsen as people get older (like everything else ;).

Why you need to know about fructose malabsorption and fructose intolerance:

Man with belly pain and toilet paper

Fructose intolerance can keep you heading for the toilet.
© Bigstockphoto.com

A study published in “The American Journal of Gastroenterology” shows that a HUGE number of people with IBS symptoms have may have problems with fructose.

Researchers tested 50 men and 133 women (183 total). 101 tested positive for fructose intolerance. That’s more than half the people!

When the people in the study drank water mixed with fructose, they got:

Water mixed with fructose??? Just about every drink you can by at the store is water mixed with fructose. Iced tea drinks, soda, juice, etc. Is this where many or all of your symptoms are coming from?

Research on fructose malabsorption shows that some people can digest small amounts of fructose, others can digest a bit more, and some people can’t handle fructose at all.

UPDATE: Avoiding fructose may cure your IBS symptoms!

According to another study I just found in the Journal of Clinical Gastroenterology, about one-third of patients with suspected IBS really had some form of fructose intolerance! When those people stayed on a fructose-restricted diet there symptoms improved or disappeared; Some of them couldn’t stand being on the fructose-restricted diet, and their symptoms stayed the same. Fructose intolerance is another piece of the IBS puzzle that may respond to dietary changes!

What is fructose and where is it hiding?

Fructose is the sugar found in fruit. It’s also in fruit juice, and is added in all kinds of foods and drinks as a sweetener. Check the labels and you will see it in lots of places.

A very common form is called “high fructose corn syrup” which seems to be in just about everything these days.

Fructose is often used as a sweetener to make food sound healthier (i.e. sweetened with “natural fruit juice,” etc.). Some manufacturers may actually believe that it IS healthier.

In some cases (like high fructose corn syrup) it is a LOT cheaper to use fructose to sweeten things.

Picture of fresh fruits.

Some of the best food, or some of the worst food. It all depends on how your bowels handle it.
© Can Stock Photo

Fructose hides in lots of foods as:

  • High-fructose corn syrup
  • Table sugar (sucrose)
  • Confectioner’s sugar or powdered sugar
  • Fruit and fruit juices
  • Honey
  • Regular soda
  • Flavored water
  • Sorbitol (a sugar substitute known to cause diarrhea)
  • Sports drinks and bottled iced tea
  • Wine
  • Many other foods (make sure to check the label for fructose, etc.)

Different foods have different amounts of fructose.

If you have trouble with fructose malabsorption, you (and hopefully your doctor or nutritionist) will need to figure out how much your body can handle, or cut out fructose entirely.

Why does fructose malabsorption cause problems?

If you eat or drink more fructose than your small intestine can absorb, then the remaining fructose travels into the large intestine (the colon or large bowel).

The fructose attracts water, which leads to loose stool and/or diarrhea. Yeast and bacteria that live in the digestive tract eat the fructose, and give off hydrogen, methane and other gasses.

All of this can set off an attack of IBS symptoms.

Fructose Malabsorption Symptoms:

Fructose malabsorption causes all of the classic symptoms of IBS, usually leaning toward diarrhea rather than constipation.

Tests for Fructose Malabsorption:

The most common test for fructose malabsorption is the hydrogen breath test. That’s where you drink a fructose sweetened drink, and they check your breath for hydrogen and other gasses.

The medical people can use that information to see if you’re not digesting fructose properly.

Then of course there’s the food elimination diet , where you remove suspected foods for a little while, and then add them back one at a time to see if they cause problems.

Fructose Malabsorption or Fructose Intolerance Diet:

Some people can completely cure their IBS symptoms by eliminating fructose from their diet. For others (like me), it’s just one piece of the IBS puzzle.

Here’s what works for me, and maybe for you:

I find that I can eat medium amounts of non-sugary fruits, and small amounts of high fructose corn syrup (in barbecue sauce for instance). Also, If I eat fructose as a small part of a meal I’m fine.

No fruit juices, or syrupy drinks and no dried fruits.

If I eat too much fructose all by itself I’m in so much pain I feel like I need to go to the hospital!

Going all the way. Cutting fructose out of your diet.

If you can’t handle fructose at all, getting it out your diet is going to be a real challenge. You’ll to remove the items in the list above, and you’ll have to check food labels constantly. Fructose hides everywhere!

You should really talk to a Nutritionist to help you develop a plan. You don’t want to get sick (with malnutrition) while trying to get well.

Some other things you may need to know:

The Food Elimination Diet page has information about finding which foods may be sensitive to.

See the Food Intolerance page for other foods that may be causing you problems.

The Lactose Intolerance page – Lactose is a sugar like fructose that many (most) people have trouble digesting.