Types of protein

Protein plays an essential role in building and repairing your body. But whether it helps a fingernail to grow or heals a sore muscle, for example, depends on the make-up of the protein.
Proteins consist of smaller units called amino acids, which can link together in many combinations to form chains. Some amino acid chains are created by your body, but those called essential amino acids must come from your diet. Although all animal and plant cells contain some protein, the amount and the quality of the protein varies a lot.
High biological value foods contain enough indispensable amino acids for an adult diet and are considered to be good quality protein. Meat, fish and eggs sit in this category.
Low biological value foods don't contain enough indispensable amino acids. Plant foods, such as pulses, nuts and seeds, are in this group.
Advice for vegans and vegetarians
Some plant foods are low in one kind of amino acid whereas other plant foods are higher in that amino acid. By eating a well balanced diet that contains a variety of foods you can get all the amino acids you require. Previously it was thought that for vegetarians to obtain enough protein different plant foods had to be combined in the same meal in order to balance the amounts of amino acids, known as protein combining. Now it's believed that this isn't necessary and that eating a range of plant foods over the course of a day will provide all the essential amino acids the body needs.
Foods such as eggs, nuts, seeds, beans, pulses, vegetable protein foods and soya products all contain protein. There are also small amounts in grains and dairy products.

Did you know...?
Eggs contain all eight essential amino acids, making them a perfect source of protein. However, you'd have to eat at least eight eggs a day to get all the protein you need. Be sensible; include them as part of a balanced and varied diet.

How much is enough?
Health professionals recommend that protein makes up ten to 15 per cent of your diet. They suggest men eat 55.5g protein a day and women eat 45g. In real terms, eating a moderate amount of protein - in one or two meals every day - should give you all the protein you need.
The need to eat protein every day is worth emphasising, because your body can't store it - you can't stock up on it by bingeing on protein once a week, for example.