Food is any substance consumed to provide energy and nutrients for the body. The human body requires a wide range of nutrients to grow, repair tissues, produce hormones and regulate internal processes. During the early stages of evolution, people got most of their nutrients by hunting and gathering and eating plants and animals that grew or lived in their immediate environment. With the advent of agriculture, however, humans settled in one place and began to cultivate crops and raise livestock. Food became easier to obtain, and the variety of foods available increased as new technologies developed for growing and preparing them.
In general, a healthy diet contains plenty of fruits and vegetables, whole grains, low-fat dairy, lean meats and fish. It also limits added sugars, saturated fats and salt. Many countries have national nutrition guidelines that suggest the amount of each type of food to eat daily.
The most common types of food include cereal grains, such as wheat, rice, corn (maize) and oats; legumes, such as beans and peas; and fruits, such as apples, bananas and berries. Fruits and vegetables are full of vitamins, minerals and dietary fiber, which helps keep the digestive system working properly.
Eating a wide variety of foods is important because different foods provide different nutrients. Some of these nutrients are essential for good health, while others help prevent disease and keep the body functioning normally.
Besides providing energy, food provides enjoyment and socialization. Different cultures have special foods that are part of their culture. Many also use food to express their beliefs, values and traditions.
Diets vary greatly from one country to another, even within the same continent. Geographical factors, such as weather and soil conditions, explain some of this variation. People who live near the ocean might eat greater amounts of seafood than those who live farther inland, for example. And people who live in cool, rainy regions might rely more on root vegetables such as potatoes than those in warmer, drier climates, where vegetable crops grow more quickly.
Changing the way you eat can make a big difference in your health. Try to eat more fruits, vegetables, whole grains and proteins while limiting unhealthy fats, salt and added sugars. And be sure to drink enough water.