Food is the substance consumed to sustain a human being and supply energy. It is usually made of plants, but may also be derived from animals or other microorganisms. Food provides the body with nutrients, such as carbohydrates, proteins, fats, vitamins, minerals, and water. It is important to eat a balanced diet so that the body gets all of the essential nutrients.
A person’s diet may vary according to culture, religion, climate, and availability of foods. A healthy diet low in fat, salt, and refined sugars helps a person maintain a proper weight and reduce the risk of chronic health conditions, such as heart disease and diabetes.
In the United States, people can obtain a variety of foods by farming, gardening, hunting and fishing, or purchasing them from stores or restaurants. Many foods are preserved for longer periods of time using techniques such as canning, freezing, drying, or pickling. Food science is the study of how food is produced and prepared.
People’s diets can vary widely between countries, and even within a country. These differences are often due to geographic factors, such as climate or the availability of different crops. Local traditions and customs also play a role in the selection of foods. For example, English tradition encourages the consumption of roast beef with Yorkshire pudding, a type of bread.
The nutrient content of foods can vary significantly, depending on the type of food and the way in which it is cooked or stored. For example, the nutrient content of fresh fruits and vegetables is much higher than that of dried or frozen versions. A person’s eating habits can be influenced by the cultural significance of foods, such as the ritual use of certain foods during holidays or weddings.
Staple foods are inexpensive and provide a good source of starch for energy, protein, some micronutrients, and dietary fiber. Examples of staple foods include wheat, rice, corn (maize), potatoes, beans, and lentils. People who eat a vegetarian diet rely on these foods to get the protein and other nutrients they need without eating animal products.
Any food that has been changed from its natural state is considered processed. Virtually all of the foods sold in supermarkets are processed to some extent. For example, an apple goes through several processes before it is sold to a consumer, including washing, cleaning, cutting, milling, heating, pasteurizing, blanching, cooking, canning, freezing, drying, mixing, and packaging. Eating a diet that is high in processed foods can lead to obesity and poor health. A person can improve the quality of his or her diet by choosing to eat more fresh fruits, vegetables, and whole grains and avoiding foods that are high in fat, salt, and refined sugars. This diet can lower a person’s risk of heart disease, high blood pressure, and some cancers. It can also help prevent depression and anxiety. A person who eats a healthy diet can live longer and have more energy. He or she will also be less likely to develop chronic health conditions, such as heart disease and type 2 diabetes.