Food is an essential component of human health and well-being. It provides nutrients, such as protein, carbohydrates, fats and vitamins, which are required for energy production, growth and reproduction. People eat foods from various sources, including fruits, vegetables, legumes, meat, fish and dairy products.
The right amount of nutrients must be consumed in a balanced diet to maintain good health. This includes a variety of food types, grouped together as a nutritional pyramid (see below). It should include enough cereal grains and other plant-based foods; fruit and vegetables; and animal-based foods such as meat, poultry, fish and eggs.
Nutritionally adequate eating is the basis of a healthy diet and a preventive strategy to avoid chronic disease, such as obesity and diabetes. It is also important for maintaining a normal weight, improving mental health and stimulating the immune system.
Meat, poultry, fish and other offal are rich in proteins and other essential micronutrients such as iron. They are a particularly good source of iron if eaten in combination with vitamin C-rich foods (such as fresh fruits and vegetables).
A typical diet for children should contain a variety of foods, from all food groups, to provide sufficient protein, calcium and other minerals. It should also include at least five servings of fruit and vegetables a day.
Legumes are an essential part of a healthy diet, providing complex carbohydrates, fibers and some B vitamins. They are especially important for children, who are growing rapidly and need extra fibre to help their bodies absorb more nutrients.
Carbohydrates should be consumed in every meal, since they are the primary energy source for most of us. Examples of carbohydrate-rich foods are pasta, rice, bread, potatoes and quinoa. It is a good idea to limit the intake of processed foods and sweets, as these can add excess sugar to the body.
Milk, cheese and other dairy products are excellent sources of protein, calcium and other essential micronutrients such as zinc and B-group vitamins. They are particularly important for pregnant women, nursing mothers and children under the age of one.
Vegetables are also a good source of protein, fibre and essential micronutrients such as iron and B-group vitamins. They are a particularly good source of vitamin C and should be included in every meal.
Other foods, such as nuts, seeds and olives, are also nutritious and should be eaten regularly. They are a good source of potassium, folate, iron and other vitamins.
The right amount of dietary fibre is essential to a healthy digestive tract, and soluble dietary fibre can help with constipation. It also has anti-inflammatory properties and is an important component of a healthy cardiovascular system.
Phenolic compounds are natural substances in many foods that give them a flavour and colour. They are often used as an antioxidant, helping to protect the body against diseases and premature aging.
Some people are more sensitive to phenolic compounds than others, and high levels can be harmful. These compounds are especially common in vegetables, but they can also be found in some fruits and milk products.