A study carried out by specialists from the Center for Biomedical Research in the Network-Physiopathology of Obesity and Nutrition (CIBERobn), concludes that ingest large amounts of fructose-based sweetened drinks, for a long period of time, causes energy imbalances in the body and alterations in the metabolism, as the development of resistance to leptin, hormone responsible for regulating the level of lipids in the blood and blocking the appetite receptors in the hypothalamus.
Metabolic alterations of this type are especially serious in children and adolescents who, in addition, tend to be large consumers of soft drinks. Resistance to leptin is related to overweight, so the abundant intake of these drinks during childhood and youth can lead to obesity in adulthood.
The sugar of the fruit
Fructose is a monosaccharide found in fruits, and is the sweetener most commonly used to sweeten soft drinks. Foods contain two different types of sugar, monosaccharides (basic units of sugar such as fructose and glucose) and disaccharides (the union of two monosaccharides, such as white sugar that is extracted from sugar cane).
Experts have always considered fructose, the fruit sugar, as a beneficial food, because it does not increase the production of insulin, unlike glucose and other carbohydrates. It only contributes four calories per gram, and is indicated for diabetic patients, since it does not cause abrupt elevations of blood sugar. However, CIBERobn researchers have found that fructose incorporated in processed foods, especially in the case of liquids, can cause overweight, by damaging the body's energy compensation system and hinder the assimilation of calories.
Dr. Miguel Ángel Martínez Olmos, coordinator of the study, points out that fructose tends to raise the level of triglycerides in the blood, and this constitutes an excess of energy that the body is not able to burn if consumed in large quantities.
The moderate intake of this product is not dangerous, but it is important to bear in mind that the amount of fructose present in two liters of soda is equivalent to that contained in 20 liters of natural fruit juices, and Dr. Martinez warns that the consumption of that amount of refreshments "is not so crazy to ingest a day, when it is a food almost essential in the diet of today's society."