Proteins, the structure of the body
This group, for example, is the main group of foods in the body, this because they participate in the formation of muscles and almost all cellular structures of the body. In addition, they are responsible for the formation of enzymes that control the body’s chemical reactions and antibodies. However, after being ingested, proteins are divided into small units called amino acids, still in the digestive process. When absorbed by the blood, amino acids are taken to the cells, where they gather and form new protein molecules. Each protein molecule has thousands of amino acids, formed by atoms of carbon, hydrogen, oxygen, nitrogen and even sulfur. Most animal foods provide protein. The best known are: red meat, chicken, fish, eggs, milk, cheese, beans, soy, peanuts and even pine nuts.
Carbohydrates, energy of the body.
On the other hand, carbohydrates are considered one of the main sources of energy in the body. That is, it is the fuel that makes the organs and muculos built by proteins work. They are found in cereals such as rice, wheat, oats, corn and in derived foods. The derivatives are: bread, pasta, flours. They are also found in fruits, roots and tubers such as banana, beetroot, cassava and potatoes. The common white sugar is nothing more than a refining of natural vegetables, such as sugarcane, possessing a high concentration of glycides. On the other hand, honey is a natural refining with high concentration of carbohydrates. A diet consisting only of carbohydrates leaves the body weak.
Types of carbohydrates
There are two types of carbohydrates: the simple and the complex. Simple ones, such as glucose, are absorbed directly into the bloodstream without the need for digestion. Complexes, such as ordinary sugar and sucrose, are formed by two molecules, one of glucose and one of fructose, and are broken down before being absorbed.
Lipids, Form Energy Reserves
Also known as fat or oils, lipids can be found in two ways:
1) Excess glycides, exceeding the limit that the liver stores and being transformed into fat.
2) By eating animal orgiem foods (lard, bacon, butter) or vegetable (oil, olive oil, avocado, peanut, coconut, etc.).
Lipids are located under the skin and around some organs, They function as thermal insulators and as energy for the body in the lack of carbohydrates, turning into sugars and burned.
Food groups: Vitamins, regulators and protectors
Vitamins, for example, aid enzymes by increasing the speed of the body’s chemical reactions. They can be classified into two groups: liposoluble and water-soluble. Fat-soluble fats dissolve well in animal feed fats such as vitamins A, D, E and K. Water solubles dissolve better in water and are found in cereals, vegetables and fruits, such as B vitamins and vitamin C. Vitamins absorbed from foods are healthier than those found in tablets, fortifying, among others. In addition to having act as coenzymes, vitamins protect the body.
Food groups: Water and minerals
Most of our bodies are made up of water. We have to take a lot of liquid, because much of the water in our body goes away through urine, perspiration, feces and breathing. We can endure weeks without eating, but without water. Minerals are important for the formation of our bones and blood.
Examples of minerals
Calcium and phosphorous: They are necessary for the formation of bones and teeth, for the functioning of nerves and muculos, and for blood clotting. Its lack causes rickets in children, osteoporosis in adults and can be found in milk, cheese, eggshell.
Iron: It is responsible for the formation of hemoglobin in red blood cells. In small doses causes anemia, which consists in the decrease of red blood cells. It can be found in red meat, beans, ox figs, lentils, curds, eggs and dark vegetables.
Iodine: It is part of the molecules of thyroid hormones. Its lack causes goiter, an exaggerated increase of the thyroid, as well as cretinism, a weakness and retardation in walking and talking. It is present in crab, crab, lobster and other seafood, in addition to iodized salt.
Source: SANTOS, Maria Angela dos, Educational Biology. São Paulo, Attica, 1987