The Basic of foods and nutrients you need to know
Food is energy for life. We need food to provide the fuel that enables us to move and keep warm. Food also provides the essential materials that we need to build, repair, and maintain our body tissues and organs, and keep us healthy. The substances in food that accomplish these functions are called nutrients. There are two main categories of nutrients: macronutrients (including carbohydrates, protein, and fats), which are the basic building blocks of nutrition, and micronutrients (vitamins and minerals). More details: The six categories of nutrients.
We need to eat plenty of macronutrients in our daily diet, whereas micronutrients, although essential, are required in much smaller amounts. Water is not normally considered a nutrient, but it is a necessary component of all foods and is essential to life.
Source of energy
Food gives us the power we need to get up and go. Our bodies are continually burning a mixture of macronutrients for energy that enables us to be active. Even when we are resting, we need the energy to keep our lungs working, hearts beating, and other essential body processes ticking along.
We all need a certain number of calories to provide us with energy throughout the day. The amount of calories in food is how much potential energy a portion of food contains. This varies depending on the type of food.
For example, a gram of carbohydrate or protein contains 4 calories, and a gram of fat contains 9. Exactly how many calories we need daily depends on our height, weight, age, gender, and activity levels. In general, adult men need about 2,500 calories a day, and adult women about 2,000 (children need fewer).
To maintain good health, we need to eat a well-balanced diet that contains an adequate but not excessive amount of carbohydrates, proteins, and fat.
They are the chief source of energy for body functioning and muscle activity. Eating a wide variety of fresh foods, especially fruit and vegetables, helps ensure that we get the vitamins and minerals that scientists know we need for good health.
Foods such as bran are rich in fiber. This is the part of plant foods that we cannot digest. Strictly speaking, dietary fiberis not a nutrient, but it still plays a role in keeping us healthy.
Vitamins and minerals
Our bodies cannot make all of the vitamins we need, so we must obtain them from the foods we eat. Vitamins are essential to human metabolism. Minerals are found in the environment, but we cannot make them. We need to eat plants and meat that have absorbed minerals.
- Bread provides carbohydrates.
- Meat is an excellent source of protein.
- Eggs are a vegetarian source of protein.
- Fish provide healthy fats.
- Bananas are a good source of the mineral potassium.
- Dried fruit is a good vitamin and mineral-rich snack.
- Nuts supply vitamin E.
- Dried peas and beans are an excellent vegetarian source of the mineral iron.