Fructose: A dangerous sweet

Published: 11/12/2013 - Updated: 07/20/2017

Fructose is a monosaccharide (simple sugar) that the body can use as energy and it is known as fruit sugar, due to its origin. Since it doesn’t raise glucose levels abruptly (because of low glycemic), it was considered to be a good substitute for sugar. However, new research has shown that perhaps it is not.

According to several studies, excess fructose consumption can lead to obesity and later diabetes as a result because it facilitates the accumulation of fat.

Fruit and sugar

Although fruits contain fructose, this is not harmful; in fact it is advisable to eat fruit daily. However, when fructose is consumed as part of processed foods, i.e. when used to sweeten soft drinks, cookies, pastries, jams, juices, etc., it can contribute to obesity, since it is in large quantities and usually made with corn syrup, sweetened with a high dose of fructose.

Metabolism of fructose

While glucose requires insulin to be absorbed by the cells of the body, of which the excess is stored in the liver and muscles as glycogen, fructose has another way of staying in the body. Fructose is absorbed in the intestine and stored directly in the liver as glycogen. The problem is that glycogen acts as a store of energy and this is converted into fat when we are consuming more calories than we are actively using, thus promoting obesity and other diseases such as fatty liver disease, cardiovascular problems, resistance to insulin and, more worryingly, diabetes.

Some studies further suggest that fructose could be even more harmful than glucose as its consumption promotes greater fat gain than when not consuming foods containing it.

In addition, consumption of corn syrup with high fructose increases appetite because it can inhibit the secretion of leptin, the hormone responsible for satiety.

Consumption in moderation

Pay careful attention to your consumption of sugars, both coming from fruits such as fructose and table sugar, as excess sugars, refined above all, can be harmful to the body. It's best to consume through foods in their natural state, so it can be used to sweeten foods. Remember to use sugar in small amounts, especially if you have diabetes.

How to reduce consumption?

Here are some tips you can follow to avoid eating this type of sugar in excess:

Avoid fizzy drinks: These drinks, and sugary drinks in general, should be substituted for natural juices, mineral water and tea. Try to limit products such as cookies, breads, jams or foods that are sweetened with high amounts of fructose and/or corn syrup.

Eat fruit: Juices have a high glycemic index, meaning they can increase glucose levels in the body sharply. Fruits like mango and banana are also high glycemic, so it is recommended to consume them in small portions.

Sugar Substitutes: Use zero calorie substitutes like steviabut do not abuse their consumption. Ask your doctor how much you should consume each day.

Check the labels: Many products are often labeled as "sugar free" but may occasionally contain it among their ingredients, sometimes included in sugar cane juice, honey, fructose syrup, fruit juice or fructose as a sweetener, so you should always read the label.

If you are diabetic, check your glucose in the morning and after every meal. This will help you to know how to manage your meals and also the amount of carbohydrates you should consume at each meal.

About the author
  • Miriam Reyes

    Miriam Reyes is a professional expert in nutrition and dietetics. She has more than 12 years of experience in caring for patients with overweight and eating problems. She studied at the Universidad del Valle de Atemajac (UNIVA), where she obtained a degree in nutrition. Linkedin profile.