The blood in your body
Your body has around 4-6 litres (8.5-12.5 pints) of blood, made up of red blood cells, white blood cells and platelets, in a liquid called plasma.
There are four main blood groups - A, B, AB and O. Each of these can be positive or negative, so there are eight different variations of blood in total.
Blood types react differently to each other, so some are incompatible with others. O negative can safely be given to anyone. Some blood groups are more common among some ethnic communities, so donations from people of all backgrounds are needed.
What is donated blood used for?
Hospitals and doctors need donated blood to treat a lot of different illnesses, and it's also used in most surgical operations. On most days, there is less than a week's supply of blood in the UK's blood banks.
How do I give blood?
It's simple, just find your nearest venue and a nurse will guide you through the session. Watch the virtual blood donation session to find out exactly what happens.
When can I give blood?
You can start giving blood when you are 17. As long as you generally fit and healthy and weigh over 50kg (7st 12lbs) you should be able to give. If you're not 17 yet, why not pledge to give blood when you are?
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