Carbohydrates are the sugars which, alongside the fats the body takes up, are used by the human body as a fuel and source of energy to enable body and mind to function.

Carbohydrates have a direct impact on our blood sugar, unlike fats that impact on our cholesterol.

Which is why it is important for people affected  by diabetes to be aware of the amount of carbohydrates contained in any given dish: the amount of carbs in the ingredient, the amount of carbs in the meal as a whole.

Being aware of carbohydrate levels enables diabetics to better direct their treatment by opting for dishes that have less sugar and/or by adapting their insulin intake.

Carbohydrates are often expressed in portions or in bread units.
For Belgium the following applies:  1 carbohydrate portion = 12.5 grams CH = 1 slice of brown bread = 1 bread unit
One of the reasons why this system was developed was to make it easier for diabetics to compare foods based on their carbohydrate content, enabling them to swap their intake for insulin and vice versa.

Which explains why some people continue to refer to a CH exchange diet : E.g., 1 slice of brown bread (30 gr) = 1CH exchange value = CH portion
1 slice of brown bread = 75 gr boiled potatoes= 50 gr boiled rice = 50 gr pasta

Sadly, these rules are not identical at an international level.

In the United States for instance, the following applies: 1 carbohydrate portion = 15 grams CH. Which means a difference of 1 CH portion compared to Belgium with every 5 portions.

Which is why ZUCSU will express the calculation in a given dish in grams of carbohydrates. Users can convert this themselves into CH portions or CH exchange values in accordance with their own (national) systems if they choose.


Not all carbohydrates are taken up by the body at quite the same pace: some are taken up very quickly whereas others take longer.

This will also have a major impact on the pace with which the blood sugar  levels rise. Hence the terms slow sugars (referred to as complex sugars in English) and fast sugars (simple sugars).

By using the glycaemic index, diabetics find out whether a certain food is slow or fast. This index is also defined by other factors such as the type of carbohydrates, the association with other foods, fibres and the method of preparations, which can all act to speed up or slow down the uptake by the human metabolism.

This may cause a given dish which contains more CH for instance, to produce a lower glycaemic index, which means the blood sugar level rises less quickly and vice versa.


Every diabetic should be aware of his personal scheme: the scheme that was discussed with the dietician and the diabetologist in consideration of the patient’s work, lifestyle and personal preferences.

A daily scheme can be drawn up that sees the carbohydrates distributed per meal. Understanding this scheme makes it easy to swap around meals or dishes using the swap system.

By being aware of their insulin sensitivity, diabetics who inject insulin can adjust their insulin intake depending on the meal or dish. Awareness of one’s correction coefficient allows for the insulin dose to be adjusted:

1  unit of insulin for .. x..  grams of carbohydrates

By having information on the glycaemic index available to them, or by having a due understanding of the relevance of the time of intake of faster sugars, users can adapt the time of injection (before/during/after the meal).

Which is why, if insulin users are insufficiently aware of their individual scheme, it is advisable for them to consult their dietician, and their diabetologist regarding the correction coefficient.