Hereditary Fructose Intolerance is a genetic error of metabolism that causes fructose malabsorption. When fructose is ingested, it must be absorbed by the intestinal cells and the body must metabolize it correctly. However, there are people in whom this does not occur, as they lack the fructose enzyme (aldolase B). This is a consequence of a congenital error.
This deficiency generates the accumulation of an intermediate product of fructose degradation that is toxic for the organism.
Symptoms of Hereditary Fructose Intolerance
The symptoms it usually causes are diverse. From a failure of medro, nausea, vomiting, dehydration, hepatic dysfunction, hypoglycemia and yellowing of the skin and mucous membranes due to an increase in bilirubin.
Most of these symptoms appear with the introduction of fructose-containing foods during lactation. The good news is that with early diagnosis and good dietary management, symptoms can be improved. Thus, although IHF is a lifelong condition, its consequences can be minimized.
Biochemical and genetic tests should be used for diagnosis. And, although the disorder usually appears at a very early age, sometimes the diagnosis can be later because children acquire an aversion to fructose products but it is not until later that they present these marked symptoms.
Creating a proper diet
Treatment is based on a strict diet prohibiting the consumption of more than 1-2g of fructose, sorbitol or sucrose daily. Therefore, in order to follow the diet successfully, it is essential to avoid any food containing fructose. It is also recommended to read the labels of all the products we consume, although very few manufactured foods can be safely consumed having IHF.
Fructose is found naturally in honey, fruit, vegetables and other plant foods and is also added as a sweetener in diet or diabetic products and is also used as an excipient in medicines.
For its part, sucrose is found in sugar, whether white or brown, and is therefore found in many sweet products such as cookies, desserts, breakfast cereals or biscuits. In addition, some fruits and vegetables contain it and it is also used in the production of some syrups and children’s medicines.
Finally, sorbitol can be found in fruits and vegetables but it is mainly used as a sweetener in many dietary products.
On the negative side, in a fructose-free diet there are insufficient sources of Vitamin C, so supplementation with this nutrient is recommended. In addition, it is also advisable to supplement with Folic Acid as it increases the activity of glycolytic enzymes.