Our human body requires several types of nutrients that should be acquired mainly from our diets, in order for each of our bodies to be able to grow, maintain, and repair itself continuously. Our diet should be varied to contain foods from all the groups of the food pyramid in adequate amounts. Some nutrients called fuel nutrients are needed to obtain energy (such as carbohydrates, lipids, and proteins). This energy is measured in calories. Another kind of nutrients are regulatory nutrients that are required to regulate how our body uses energy from fuel nutrients (such as water, minerals, and vitamins).
Fuel Nutrients:
1-Carbohydrates: These are the main source of fuel and the foundation of a healthy diet, by which more than half of our body’s energy needs should come from. They are classified as starches and sugars. Glucose, for example, is a simple sugar that all of our body cells use for energy, and when combined into longer complex chains they constitute starches. We also have what is called fiber, sometimes called the seventh nutrient, but it doesn’t provide energy.
2-Lipids: These are very concentrated energy sources such as fats and oils. They have 3 main functions:
*form the bilayer foundation of cell membranes and organelles
*act as a solvent for fat-soluble vitamins and essential fatty acids
*gives satisfaction after eating because of the long time they take to get digested
3-Proteins: These are the only source of nitrogen, which the body needs to make small molecules called amino acids that are then carried out by most carrier molecules like enxymes, muscles, hormones,… The body makes most of them , but some should be taken from the diet and these are called essential amino acids.
Regulatory Nutrients:
1-Water: It’s the most vital nutrient. It acts as a lubricant, solvent, and coolant. The adequate amount is established when we drink one-half an ounce daily for each pound of body weight. To know if ur water intake is adequate, watch your urine for its color. If it was pale to almost clear, then ur intake is adequate, but if it was dark and concentrated, then you should drink more water.
2-Minerals: These are inorganic compounds, they aren’t made by living things, and they aren’t broken down within the body. Plants absorb them from the soil or water, and we in turn can get them from the plants or from plant-eating animals. They are needed for bones, nerve and muscle function, production of certain enzymes, etc…
3-Vitamins: They are needed in very small amounts. They mainly activate enzymes and regulate energy release. They are of two classes:
*Fat-soluble (A,D,E, and K) excessive amounts of these can be dangerous, for they can accumulate in body fat and liver.
*Water-soluble (B and C) easily dissolve in water rather than being stored in the body, and any excess wouldn’t be harmful because they will be excreted in the urine.
Questions:
a) What are the six nutrients that the body requires for good health?
b) What are the main functions of lipids in the body?
c) Name two kinds of vitamins and mention the difference between them
