Fructose Malabsorption

Bitten Apple Core

The old adage “an apple a day keeps the doctor away” is not without merit. Apples are nutrient dense and eating them on a regular basis can be a health enhancing activity- unless you suffer from fructose malabsorption disorder. This malady is referred to as fructmal, and eating apples or any food high in fructose can be anything but health enhancing.

What is Fructose Malabsorption?

Fructose is a naturally occurring sugar found in many foods, most notably fruit. In addition, it is used in food manufacturing to sweeten many processed foods and beverages. Fructmal impairs a person’s ability to absorb fructose. Normally, fructose is absorbed in the small intestine, with aid of a protein known as GLUT-5. If this protein either is not present or inactive, the unabsorbed fructose reaches the large intestines, where it is rapidly fermented by colonic bacteria to acids and gases, predominantly hydrogen, but in some people it can be methane. This causes both gastrointestinal symptoms and the proliferation of intestinal bacteria and yeast, which turns into fructose.

It’s important to know that malabsorption is the causative factor in fructmal, not intolerance. People with fructmal have no problem tolerating fructose, their small intestines simply cannot absorb it. There is a genetic disorder that is far more serious called Hereditary Fructose Intolerance, which in some cases can be life threatening.


The symptoms of fructmal are mainly digestive-abdominal pain, gas, bloating, nausea, acid reflux, diarrhea and constipation. However, depending on the severity of their condition, it is not uncommon for victims of fructmal to also experience depression. Although this may seem strange or severe, it isn’t.

When fructose makes it to the large intestine it degrades into tryptophan, an essential amino acid the body needs to make serotonin, a mood regulator. Studies indicate that fructose malabsorbers do indeed have lower tryptophan levels than normal controls. They also experience reduced serum zinc and folic acid levels, which may increase the risk of depression. The severity of the symptoms varies greatly among those with this affliction. Some people seem to be able to consume small doses of fructose without problems while others are symptomatic after ingesting even minute amounts of the sugar.

Foods to Avoid or Reduce

  • Sweetener such as high fructose corn syrup, honey and agave nectar.
  • Fruits such as apples, dates, figs, grapes, pears, prunes, melons, watermelons, mango, quince, raisins and cherries.
  • All dried and canned fruits
  • Stone fruits that contain sorbitol, such as plums, peaches, nectarines and apricots.
  • Sugar free gum and candy sweetened with sorbitol and other sugar alcohols.
  • Fructose such as rye, wheat, spelt, coconut cream and milk, tomato paste, artichokes, onions, asparagus, inulin, chicory and FOS.


A definitive cause for this affliction has yet to be established, but several contributing factors have been insinuated, including:

  • Overuse of high fructose foods, especially those sweetened by high fructose corn syrup
  • Bacterial abnormalities in the gut
  • Inflammation
  • Stress


  • Use dextrose powder to sweeten baked goods
  • Allow fruits like bananas to ripen completely to increase their glucose content
  • Eliminate fructose for two weeks and then reintroduce it gradually to determine your threshold
  • Consume fructose on a full stomach, after meals
No comments yet.

Leave a Reply