Fructose Intolerance


Fructose is a sugar (carbohydrate) which is naturally present in fruits, some vegetables and honey. It is also used as a sweetener in some soft drinks and fruit drinks. When the body doesn’t absorb fructose properly, it is called fructose malabsorption or fructose intolerance. This is a common condition and different from hereditary fructose intolerance, which is a rare, genetic and sometimes fatal disorder affecting the liver.


Fructose malabsorption occurs when the body is not able to break down fructose during the digestive process. When undigested fructose reaches the intestines, it reacts with naturally occurring bacteria and generates carbon dioxide and hydrogen gases. This in turn can cause bloating, abdominal pain, heartburn, diarrhea and gas. It is important to recognize that high-fructose corn sweetener is commonly added to prepared foods and is present in high concentrations in non-diet soft drinks and most fruit juices.


The symptoms of fructose intolerance are commonly mistaken for other food intolerances or allergies because the symptoms of fructose intolerance, including gas, bloating, abdominal pain and diarrhea are nonspecific and can be present in many different gastrointestinal conditions. People who have irritable bowel syndrome may find that fructose ingestion increases their uncomfortable symptoms.


If you suspect fructose intolerance, you may consider eliminating suspect foods and keeping a diary of your body’s reaction when foods are reintroduced. To confirm fructose intolerance, your doctor can order a breath test that checks for hydrogen. When hydrogen is detected within one hour after eating a food containing fructose, the person is regarded as being fructose intolerant. Avoiding fructose and eating a low—sugar diet is the best way to prevent the uncomfortable symptoms associated with fructose intolerance. However, many people with fructose intolerance can eat some amount of fructose without problems. Limit intake of:

  • Fruit, fruit juices and dried fruit
  • Honey
  • Sodas and other beverages containing high fructose corn syrup
  • Alcohol


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