Meat, fish, eggs and alternatives

This food group includes poultry, pulses, beans, nuts, seeds, soya products and vegetable protein foods such as quorn and seitan. They're grouped together because they're all rich in 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.

This means that if you're vegetarian or vegan, you need to do some clever combining of proteins at meal times to ensure that the amino acid of one protein (eg, soya milk) can compensate for the deficiencies of another (eg, muesli with nuts and seeds).

Because plant foods only contain some but not all the protein elements needed by your body, they need to be mixed together to ensure your good health.

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. It's quite easy to combine two or three of these to make sure you're getting enough protein. Here are some ideas for tasty combinations:

• Bran flakes with milk and sunflower seeds (grain + dairy product + seed).
• Grated cheese and baked beans on toast (dairy product + bean + grain).
• Egg fried rice with chick peas (grain + egg + pulse).
• Yoghurt dip with aubergine curry and naan (dairy product + grain).

If you're vegan and don't eat dairy products or eggs, there's no reason to feel limited. Here are some ideas:

• Muesli with nuts, seeds and soya milk (nut + grain + seed + soya).
• Tomato and lentil soup with bread (pulse + grain).
• Stir-fried tofu, vegetables and rice (tofu + grain).

How much is enough?

Health professionals recommend that protein makes up 10 to 15 per cent of your diet. They suggest that adult males eat 55.5g protein every day and adult females 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 daily 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.

This article was last medically reviewed by Dr Rob Hicks in September 2005.
First published in March 2001.