Food is a substance that provides nutrients and energy to both humans and animals. Foods are essential for the growth, repair, and maintenance of tissues, organs, and organ systems. Humans and animals need a variety of foods to achieve adequate nutrition. They need to eat the recommended amounts of food from each of the five major food groups every day.
In addition to providing energy, foods provide many different vitamins and minerals. Fruits and vegetables are excellent sources of vitamins and minerals. Many fruits and vegetables are also high in fiber, which helps to prevent stomach problems. Fresh fruits can be preserved by freezing, drying, or canning.
Protein and fat are provided by meats and dairy products. Fats provide twice as much energy as carbohydrates. Fortunately, many of the calories that come from fat can be used to help keep you full, but they also increase the risk of developing heart disease. So, limit your intake of fats.
Other types of food include grains. Grains such as wheat, corn, and rice are grown for their fibre, and can be eaten whole or refined. Whole grain foods are usually higher in fibre, and they take longer to digest than refined ones. However, some varieties of grain, such as degermed cornmeal, are enriched to remove some of the nutrients.
Oils are another type of food that can be consumed regularly. Some seeds and pulses contain omega-3 fatty acids, which can help protect against heart disease. Vegetable oils are another common oil.
Fish and poultry are other sources of protein and fat. People can eat fish and poultry raw or cooked. Fish are high in Omega-3 fatty acids, which can reduce the risk of heart disease. Fish and poultry can also be dried, frozen, or canned to preserve them.
Nutrient needs are dependent on age, pregnancy, activity, and recovery. These factors are discussed in Topics 3 and 5-10.
As a result of the changes in technology, improved methods of agriculture have allowed for a larger variety of foods. This has allowed people to enjoy food produced far from home. However, a large percentage of the world’s population does not have access to nutritious foods.
The United States Department of Agriculture (USDA) has published food patterns that specify the targets for each food group in terms of the amount of calories they should contain. For example, the USDA targets 8 to 19 percent of total calories as coming from carbohydrates. Added sugar is limited to less than 10 percent of total calories.
Sugary beverages are often a source of added sugar. Adding too many calories from sweetened drinks can contribute to weight gain, diabetes, and a decreased ability to control your blood sugar levels. Consuming only small amounts of added sugars is important for a healthy diet.
In many parts of the world, including China and India, yogurt and milk are used as a staple food. Milk is a good source of calcium, while yogurt contains some proteins.