Carbohydrates, also called carbohydrates or carbohydrates, is the most accessible source of energy for the body, providing 50-55% of total energy intake. Although quantitative carbohydrates represent only 0.3% of body weight, their importance is extremely high, with a dual role: energy and structure.
Carbohydrates are used to maintain body temperature and maintenance of vital functions and provides energy for muscular efforts.
Our nervous system, the brain and other organs such as the heart, lungs, kidneys, intestines and blood cells are especially needed carbohydrates and can not nonfunctional without them. In addition to the role of fuel for the cells, carbohydrates participates in the formation of cell membranes, connective and supporting tissue, nerve tissue, as well as some basic functional component part, such as hormones, enzymes and antibodies.
There are several types of carbohydrates:
in this category are distinguished monosaccharides (a molecule made up of elementary) and disaccharides (two associated molecules). These sugars are called “quick” because they are absorbed immediately into the blood. All except fructose, have the inconvenience of adjusting mechanisms jolted stimulate blood glucose (insulin secretion) and not quell hunger for long periods of time. The absorption of fructose is as rapid as simple carbohydrates, but only half the amount of fructose used immediately and the other half is stored as glycogen. For this reason, ingestion is not trigger the secretion of insulin.
– Glucose is found in the free state in less food comes in numerous other carbohydrates. Glucose is the main fuel of the human body and core element of glycogen.
– Fructose, honey present in the fruit, with the glucose part of sucrose in the formation.
– Galactose in the composition of lactose (milk sugar), in association with glucose.
– Sucrose, or sugar Typically, the most common in nature, it is composed of one molecule of fructose and one of glucose. It can be obtained from sugar beets and cane. It is found in fruits and vegetables.
– Lactose, the sugar in milk and milk products.
– The grains is maltose and beer.
– Complex carbohydrates: are called polysaccharides or “slow carbohydrate” as it progressively absorb the intestine. They should decompose in a first stage, the basic carbohydrate molecules (glucose, fructose and galactose) before it can be absorbed. Insulin production is better adjusted after consumption of carbohydrates slow since the release of small molecules of glucose in the blood is progressive over time. Complex carbohydrates provide energy besides (glucose) and other nutrients.
Polysaccharides are carbohydrates consisting of several monosaccharide molecules associated. The main digestible polysaccharides are:
– Starch: present in foods of plant origin, such as cereals, legumes, potatoes and some fruit (bananas, chestnuts).
– Glycogen carbohydrates animal, constituting some of the stored energy stored in liver and muscles. It consists of a chain of several molecules of glucose. Dietary intake of glycogen is almost zero, but the body is able to produce and use it during interprandiale.
Where Ourselves in Carbohydrates?
Food sources of carbohydrates are varied and carbohydrates are found in different proportions in sweet foods.
Simple sugars (mono- and disaccharides) are absorbed as such and are then available as a source of energy in the body, and the complex (oligo-and polysaccharides) are first converted into simple sugars and then absorbed. This underpins the glycemic index of foods (see below). Fruit, honey, syrups are foods that contain large amounts simple sugars, while complex carbohydrates are contained in particular in cereals and vegetables.
It was previously thought that a certain amount of carbohydrates increase blood sugar has the same effect regardless of the source of origin food. This view was refuted by actual studies that show, for example, that 30g of carbohydrates from bread and not have the same effect on blood sugar 30 g carbohydrate as fruit or pasta. Carbohydrates from white bread are refined carbohydrates, obtained by processing therefore simple structure; they will raise blood sugar faster than carbohydrates in pasta or bread interim or black, containing complex carbohydrates.
The sudden rise in blood sugar followed by a response from the body that tends to bring blood glucose levels to normal values by increasing insulin secretion. When this is done quickly and secretion