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Carbohydrates

Sugars, carbohydrates, slow sugars, fast sugars, there are so many terms referring to carbohydrates that sometimes it's difficult to know what's what. As this list shows, the family of carbohydrates comprises a widely varying range of foods both in the way that our body digests them and uses them and in the way that they are constructed.

There are two types of carbohydrates found in food:

Simple carbohydrates: composed of simple sugar units. They generally taste like sugar and are, for example, glucose, fructose, found in fruit, saccharose, table sugar or lactose, found in milk.
Complex carbohydrates: composed of chains (polymers) of simple carbohydrates all linked up, this group contains starch in particular. Their digestion, if this is possible, results in the formation of simple carbohydrates that can be used by the body. Dietary fibre falls into this category. Generally of plant origin, such as cellulose or pectin, they cannot be digested or absorbed.
The fact that carbohydrates are simple or complex does not reflect the way in which they are digested and used by the body, but only the way in which they are constructed. As a result, both types may be totally digested or, on the contrary, not at all.

What are carbohydrates found in?

Carbohydrates, particularly complex ones, are a way of storing energy for animals and plants. As a result, they are naturally present in most foods. The quantity and type of carbohydrates found are extremely variable between foods, however.
Products naturally containing a high proportion of simple carbohydrates are fruit, milk, honey and any other naturally sweet product. Digestible complex carbohydrates are naturally present in starchy foods, i.e. cereals, bread, dried vegetables (dried beans, peas, lentils, etc.), and potatoes and their derived products. Dietary fibre, a form of complex carbohydrates that cannot be digested, almost entirely comes from products of plant origin, fruit, vegetables and wholegrain products.

The manufacture and processing of foods by the food industry may also involve the addition of carbohydrates to processed foods. The purpose of these added carbohydrates may be to increase the sweet taste of food but also to improve the appearance, texture or shelf-life of processed products. The highest contributing manufactured products of added carbohydrates are fruit juices and soft drinks, sweets, dairy desserts, ice creams, breakfast cereals and biscuits.

Nutritional studies carried out among the French population show that, over the last fifteen years, the consumption of foods containing simple carbohydrates has been increasing constantly, except for fruit and milk. It is therefore simple added carbohydrates for the most part that are responsible for the increase observed. Food sources of complex carbohydrates, however, are being consumed more and more rarely, even if this reduction has stabilised over recent years.

In adults, carbohydrates are responsible for 40% of daily energy intakes, on average. Simple carbohydrates account for between a third and half of all carbohydrates consumed. Carbohydrate intake in children is higher, accounting for around 50% of the total energy intake. A higher proportion of these intakes is represented by simple carbohydrates than in adults, however. This is mainly due to a higher consumption of milk and dairy products by young children, and then soft drinks and fruit juices by older children.