It does matter where sugar comes from (I). Talking about fructose

Some foods contain sugar naturally, as is the case of fruit which in its composition has varying amounts of fructose. However, there are marked differences between consuming the sugars from fresh fruit and fructose from other foods.

That is to say, the fresh fruit that we eat can have up to 10 grams of fructose, just as it can contain a glass of soda. However, in our organism there are differences between the sugar derived from the intake of a fruit and that which is used to sweeten industrial foods.

Fructose contributes 4Kcal per gram in both fruit and other foods. Since it is processed by the liver, it can be harmful in large quantities. However, in the case of fresh fruit, our body absorbs the sugar in a different way. When we eat a fruit we are not only consuming fructose but also fiber, complex hydrates, micronutrients with antioxidant function and phytonutrients, which have a great benefit for our bodies.

Thus, when we consume fructose from fresh fruit, the blood sugar does not rise sharply as can happen with a soda. In consequence, since not so much insulin is released, the odds to form adipose tissue are lower. In addition, when we consume fresh fruit we are also more likely to satiate and self-limit consumption of other aliments, while with an added fructose to other aliments this does not happen. Without fiber and without complex carbohydrates, it is very difficult to quench hunger.


The juices leave out a big part of the fiber and keep all the sugar. Fiber, apart from the beneficial properties that it has by itself, also causes the sugar to be released into the blood in a slower way, avoiding the harmful peaks of insulin.

For example, an orange, when eaten whole, has a GI of 42, while in the case of an orange juice the GI rises to 53 (25% more), and it is basically water with fructose. Of course, the GI is much higher if it is added refined sugar to that juice, which is unfortunately quite frequent.

Dehydrated fruit

Fruits are basically water. The amount of water of the fruit varies from 92% of the watermelon to 74% of the banana. When we manipulate the food and dry it, what is more lost is its content in water and part of its water soluble vitamins. Vitamins soluble with water, will be found in less quantity, as in the case of vitamin C, thiamine and folates of the vitamin B group. In addition vitamin A is destabilized and also lost in quantity in the process of dehydration. In the case of dehydrated fruit, by eliminating all the water, the remaining content of that fruit is mostly sugar.

In we focus on sugar. However, it is important to mention that 100grams of dehydrated fruit contains a much greater quantity of fiber and vitamins not soluble in water than the fresh fruit.


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