There is some confusion about carbohydrates and their effect on the body. The body gets its energy from fat and protein as well as carbohydrates, but the body's favourite fuel is carbohydrates. There are many different kinds of carbohydrates and some are absorbed by the body more quickly than others. In that context the socalled glycemic index is often mentioned as it describes how quickly the carbohydrates of a food are absorbed in the blood. The higher the number of a food in the glycemic index, the faster the blood sugar increase.
Human beings primarily need to eat foods that provide a slow blood sugar increase because a blood sugar increase that is too quick will make the body lower the blood sugar with lightning speed using insulin from the pancreas. When this happens, you will get hungry again soon and feel like eating sweets. The only time you may benefit from consuming fast carbohydrates is in connection with hard training/fitness when energy is quickly used by your muscles. To simplify matters, foods may be split in fast carbohydrates (high glycemic index) and slow carbohydrates (low glycemic index).
The amount of fast carbohydrates should mostly be kept at a minimum level. Most of such foods are refined and prepared, with hardly any nutritional value because there are none of the vitamins and minerals that your body needs. Some examples of these foods are pastry and cookies, candy, soda pops and white bread, and also many breakfast products such as cornflakes and coco pops. Especially candy contains large amounts of added sugar and dextrose that influence the blood sugar enormously.
However, fast carbohydrates also comprise quite natural sorts of fruit such as pineapple and watermelon as well as a few vegetables such as carrots. Unlike the other foods mentioned, these foods are natural and healthy, but they should be supplemented with other foods, of course. After hard training or fitness it is a good idea to eat healthy and natural carbohydrates such as ripe fruit to quickly replenish the body's energy deposits. After training or fitness it is also important to eat proteins to rebuild your muscles at an optimum.
Slow carbohydrates are the kinds of carbohydrates that should be eaten the most. This group comprises most vegetables and most kinds of fruit as well as wholemeal bread and the like. These sources of carbohydrates are also the primary sources of other essential nutrients such as vitamins, minerals and dietary fibres. Slow carbohydrates make your blood sugar rise slowly so that your blood sugar is kept stable for a longer period of time. Dietary fibres are important to your digestion and also provide the necessary sense of satiety.
Sugar is one of the most readily absorbable carbohydrates.
Sugar as we know it is often found in large amounts in for instance candy, pastry, cookies and soda pops. Sugar is added to very many products, also products that many people find healthy, for instance fruit yoghurt, biscuits and breakfast products such as cornflakes and coco pops.
Sugar is often referred to as empty calories because it only contains calories and no vitamins, minerals or dietary fibres that could nourish your body. Sugar increases the risk of overweight because it considerably reduces your ability to feel that you have had enough to eat.
Your body does not need sugar and if you eat too much of it, the many calories will take up space instead of healthy food. In addition, sugar increases the risk of developing caries.
Starch is the most important carbohydrate energy source. Starch is found in fruit, vegetables and cereals. But there is more than one kind of starch. The starch in whole grains, for instance, is slowly absorbable and therefore healthier for your body than ground and sifted grains. White bread is made from ground flour where the protective bran has been sifted off. The starch is therefore absorbed much faster, providing only a short and low sense of satiety. The healthy vitamins, minerals and dietary fibres are typically found in the bran of the grains. Most fruit and vegetables contain slowly absorbable starch with good vitamins, minerals and fibres. The riper the fruit, the higher the glycemic index.