When fructose doesn’t get absorbed into the bloodstream through the intestinal wall like it’s supposed to, it is shipped further down the bowels and gobbled up by hungry bad bacteria. When the bad bacteria eat they make by-products such as methane and hydrogen gas that cause bloating, cramping, gas, diarrhea, and bad breath. In fact, there is a test for Fructose Malabsorption that measures the level of hydrogen in the breath. This is because the bad bacteria release hydrogen after digesting fructose which gets absorbed into the blood stream and removed by the lungs, finally expelled from the body through the breath.
So Why Can’t The Body Absorb Fructose?
There are several scenarios that would prevent the body from soaking up fructose. The first is a genetic disease that is hereditary and does not allow the body to deal with fructose, which is very rare. If there isn’t a genetic defect behind all this there are really only three things that could be going on. The bowels could just be moving way to slow in which case the fructose sits around not getting absorbed, allowing bad bacteria to feast on it, but this is also pretty rare for the small intestine (constipation takes place further along in the intestinal tract). The 2nd thing that could be going on is the GLUT5 and GLUT2 transporters could be deficient. GLUT5 and GLUT2 transporters are little escorts that guide the fructose across the intestinal wall and into the blood. If they are not around to escort the fructose it cannot be absorbed. This too has been found to be somewhat rare. The 3rd and more likely scenario is that small intestinal bacterial overgrowth is in full swing and the bad bacteria are gobbling up the fructose in the small intestine before it has a chance to be escorted to the blood stream in the first place.
The only way to stop this out of whack cycle that is causing the bacterial overgrowth and digestive unrest is (i) to stop eating sugars temporarily to starve out the bacteria and (ii) only eat things that the body can easily absorb to replace the nutrients you need to heal. That’s where the GAPS Diet comes in and accomplishes both of those things by eliminating complex carbohydrates (sugars, starches, and grains) and providing simple foods so the body can replenish the nutrients and begin to heal.
The advice of a nutritional therapist will help you to diagnose a fructose malabsorption, identify the food you must avoid and recommend the GAPS diet that suits better for you in order to heal the gut flora.
If you want to know which food contains fructose click here.