Carbohydrates are primarily made up of carbon, hydrogen and oxygen. Based on their chemical structures and how quickly they are digested and absorbed, carbohydrates can be divided into simple carbohydrates (with one to two sugar molecules; also called Sugars) and complex carbohydrates (with three or more linked sugar molecules).

Simple carbohydrates, which include glucose, fructose, sucrose, lactose and other sugars, are fast energy sources because they can be broken down quickly by the body (also see Sugars). Complex carbohydrates generally refer to indigestible dietary fibre and starch that take longer to be digested than simple carbohydrates. In addition to providing energy (1 gram of carbohydrate provides 4 kilocalories), carbohydrates have many other functions. For example, they regulate blood glucose and insulin level.


Simple carbohydrates occur naturally in fruit, vegetables and milk, etc. However, sugars can also be found as added sugars in highly refined and processed food and beverages, such as candies, jam, cookies, cakes and soda. The most common food sources for complex carbohydrates are cereals and grains, fruit, starchy vegetables (such as carrot, pumpkin, corn) and beans.

Added sugars only provide 'empty calories' because they do not contain any nutrients. On the other hand, the natural food sources of simple and complex carbohydrates not only provide carbohydrates as calorie sources, but also other nutrients such as vitamins, minerals and dietary fibre. Such carbohydrates from natural foods are considered as 'good' carbohydrates.


The World Health Organization (WHO) and the Food and Agricultural Organization (FAO) of the United Nations recommend that healthy people should get 55 - 75% of total calories from carbohydrates. Thus, for example, an individual with a daily energy intake of 2 000 kilocalories should aim for 275 - 375 grams of carbohydrates a day, preferably from complex carbohydrates and natural sugars.

Health Alert

Eating carbohydrates will not necessarily cause weight gain. Getting more calories (whether they are from fat, protein or carbohydrates) than you can burn is what causes you to gain weight.

Practical Tips for Adding 'Good' Carbohydrates

Foods rich in carbohydrates (from grains, such as bread, cereal, rice, and pasta) are at the "Eat the Most" level at the base of the Food Pyramid, reflecting their importance as part of a healthy diet. Here are some suggestions for increasing the amount of 'good' carbohydrates from the grain group and other food groups in your daily meals:



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