What is a healthy diet?

  • To keep healthy, it is vital to eat a balanced diet. This means eating foods that contain nutrients in the correct amount.

  • There are different types of nutrient, including carbohydrates, lipids, proteins, vitamins and minerals.

Find out what makes a balanced plate of food from a catering supervisor.


Nutrients are essential substances that the body needs. There are different types of nutrient, each with its own purpose:

  • Carbohydrates provide energy. They are found in bread, potatoes, rice and pasta.

  • Lipids (fats and oils) provide energy. Lipid-rich foods include butter and chips.

  • Proteins provide materials to make new cells and to repair damaged tissues, such as muscles. Beans, eggs, fish, meat and milk are high in protein.

  • Vitamins are vital in many processes. For example, vitamin K helps blood to clot and vitamin C prevents illness. Fruit and vegetables are vitamin-rich.

  • There are 16 essential minerals. These include iron, used to transport oxygen in the blood, and calcium, used in making bones and teeth.


Fibre cannot be absorbed by the body and contains no calories or vitamins. It is not, therefore, a nutrient.

Fibre adds bulk to food, and helps it to pass through the digestive system. Fibre also prevents constipation and heart disease. Fruit, vegetables and wholegrain cereals are high in fibre.


Around 70% of your body mass is water. Chemical reactions in cells take place in water and the blood transports substances dissolved in water.

You need to frequently drink water to replace the water lost in urine, sweat and breathing out.

How much?

It is important to eat nutrients in the correct amounts – too much may cause obesity and too little may cause malnutrition.

The World Health Organisation recommends getting at least half of your energy intake from carbohydrates and no more than 30% from fats. The organisation also recommends 400 g of fruit and vegetables daily.

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Where next?

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