Fructose is a naturally occurring simple sugar found in fruit, vegetables and honey. Fructose is used to sweeten foods like jellies, soft drinks, gelatin, ice cream, candy, and certain diet foods. Fructose also absorbs moisture so it helps keep baked goods from becoming stale. Fruits and fruit juices with high levels of fructose may cause gas, bloating, abdominal cramping, and diarrhea.
Sugar malabsorption is the inability of the small intestine to break down sugar like fructose for digestion. The sugar moves into the large intestine (colon) where bacteria break it down causing bloating, pain, diarrhea and gas (flatulence). The fructose molecule attracts fluids back into the colon making bowel movements loose and watery. Fructose Malabsorption is not only associated with gastro-intestinal distress but also the inability to absorb all kinds of nutrients which can lead to serious diseases like anemia and osteoporosis.
What is the difference between fructose intolerance and fructose malabsorption?
“Fructose intolerance” is a general term that describes two conditions:
Hereditary Fructose intolerance is a rare genetic condition that doesn’t produce an enzyme necessary to break down fructose. One in three people has some level of sugar sensitivity – most commonly to fructose, however around half of these people show no symptoms at all. With this intolerance it is vital to observe a strict fructose-free diet. Otherwise there is risk of serious disease including liver failure, which is sometimes fatal, and kidney damage.
Fructose Malabsorption, on the other hand, is more common and affects about 30% of people. This disorder does not result in kidney or liver damage but it can cause abdominal cramping, diarrhea, nausea, pain, and bloating. In addition, sorbitol — a sugar alcohol — is converted to fructose during normal digestion. People with fructose intolerance should avoid foods that contain fructose,sucrose, and sorbitol.
How is fructose malabsorption and fructose intolerance treated?
A fructose-free (low-sugar diet) is the best treatment. Many processed foods contain added fructose under names like “corn syrup” or “high-fructose corn syrup.”
When will I be cured from fructose malabsorption or fructose intolerance?
Hereditary Fructose Intolerance cannot be cured so a strict fructose-free diet must be followed.
Fructose Malabsorption is much easier to manage. Keeping a food diary/journal will help you decide which fructose-containing foods bother you the most. Some people can eventually tolerate small amounts of fructose in their diet.
High Fructose Corn Syrup (HFCS)
HFCS is made up of almost half glucose and half fructose and may be absorbed just as well as sucrose (regular table sugar). Items with HFCS such as soft drinks, may be tolerated well when limited to 12 oz. per day and with a meal. HFCS can also be found in canned, baked, or processed foods. In some patients, even a small amount of processed fruit juice or even foods with HFCS may cause as much malabsorption and/or intestinal discomfort as eating large quantities of fruit.
Sorbitol or Sorbose is a sugar alcohol used as an artificial sweetener and found naturally in fruits and fruit juices. It can also be found in many “diet foods” such as diet soft drinks, sugarless gum, sugar-free jelly/jam, and liquid medications. Sorbitol often creates similar symptoms as fructose – especially when fructose and sorbitol are ingested together.
- Eliminate products with ingredients that list fructose, crystalline fructose (not HFCS), honey, and sorbitol on the label.
- Avoid sugar alcohols, which include sorbitol, isomalt, lactitol, maltitol, mannitol, xylitol, erythrytol, and lactatol. These are often found in “diet or diabetic foods” such as diet drinks, ice cream, candy, processed goods, etc.
- Limit drinks with HFCS; if used, drink less than the recommended serving size, e.g., less than 12 oz. soda (may help to drink with a meal).
- Check medications for fructose and sorbitol. They are not always listed on the label, so check with your pharmacist or the manufacturer.
- Keep in mind the amount of fructose found in 2 apples or 2 oz. of honey is the same fructose as one can of soda.
- Follow guidelines below for fruits, vegetables, and other foods that are friendlier to your intestines.
- Serving size is ½ cup – recommended 1 to 2 cups per day.
- Fresh or frozen fruit may be better tolerated than canned fruit.
- Keep in mind tolerance may depend on the amount you eat at one time.
Please reference the following:
Intestine Friendly: Pineapples, strawberries, raspberries, blackberries, lemons, limes, avocado, bananas*, rhubarb, orange
Foods to Avoid: Prunes, pears, cherries, peaches, apples, plums, applesauce, apple juice, pear juice, apple cider, grapes, dates
Questionable Foods/Limit intake: Other fruit/juices or drinks, Sugar-free jam/jelly, dried fruit, canned fruit in heavy syrup and other fruits