Carbohydrates, proteins and fats

A balanced diet should contain a combination of all the nutrients that are required to keep the body healthy and in good repair. This includes the right balance of so-called ‘macronutrients’ – carbohydrates, proteins, and fats.

Carbohydrates

Carbohydrates break down inside the body to form glucose, which is the basic fuel for the body, providing energy. Foods containing carbohydrate include products rich in starch and/or sugar, e.g., bread, pasta, rice, cakes, and biscuits, and provide 4 kilocalories per gram.

Proteins

Proteins are the building materials of the body, helping with growth and repair of body tissues, e.g., muscles, skin. Foods containing protein, e.g., dairy products, meat, nuts and pulses, provide 4 kilocalories per gram.

Fats

Fats serve as an energy store and insulator. They also supply ‘essential fatty acids’, which are required to help the body absorb some necessary vitamins. Fats are high in calories (9 kilocalories per gram), and although certain types should be eaten in moderation (see box, below), some people who have difficulty gaining weight may be advised to eat more high-fat foods.

Saturated and unsaturated fats Saturated fats can cause an increase in blood cholesterol. They are also known as animal fats as they are found mainly in animal products such as fatty cuts of meat, lard and dripping, some margarines and dairy products such as full fat milk, hard cheese, cream and butter, and in cakes, biscuits, pies and pastries. Saturated fat may also be found in some vegetable oils such as coconut and palm oil. Unsaturated fats may lower blood cholesterol, and include the polyunsaturated fats found in sunflower, corn or soya oil, and the monounsaturated fats found in rapeseed (canola) and olive oil.