The food we eat supplies us with sustenance we need to keep up our lives. Food consists of variety of different substance, nutrients, which supply us with nutrition. Nutrients supply energy and raw materials for the body and allow our tissues to be built up and broken down according to need.
All nutrients can be separated into five basic groups.
All of them are made by plants from sunshine, air, earth and water. We can eat them as vegetables foods or as animal foods.
Carbohydrates and fats are mostly needed for our body as sources of energy to keep us warm, moving, thinking, digesting and metabolizing.
Proteins are the raw materials which need to build and repair body tissue and a huge variety of essential chemicals called enzymes. High level of protein is contained in such vegetable foods as peas, beans, lentils, nuts and cereals, as do flesh foods and animal-derived products such as eggs and cheese.
Vitamins are vital chemicals that help the enzymes within body cells manage the process of metabolism.
Minerals also play a part in a wide range of chemical and electrical process within the body. Both vitamins and minerals are found in many different food stuffs.
Besides five basic nutrients, our food contains other non-nutrient substances, such as fibre, water and chemical additives, which can have important effects on health as well.
Fibre provides the bulk in food that enables our bowels to work efficiently and helps to protect us from bowel disease and high blood cholesterol levels.
Water from food with the water we drink helps our blood to flow, forms the basis of our body fluids and plays a vital part in our digestion and metabolism.
Chemical additives affect the appearance, flavor and storage qualities of food and may have an influence on health.