To donate blood you must be:

Aged between 17 and 60 In general good health Weigh over 50kg

At present, the NBS has 1.85million active donors on its database. However, this represents only 6% of the eligible public.

It is estimated that 10,000 donations are needed every day to meet the requirements of hospitals across the country.

Traditionally, blood stocks can dip by up to 10% over the festive period as the surge in winter colds and flu mean fewer people can donate.

Chris Hartley, NBS communications manager, said: "The demand for blood never relents, everyday we need to collect 10,000 pints of blood.

"We need to recruit 400,000 new donors next year to ensure that we keep blood stocks healthy, and so that patients can continue to get the life saving treatments they need when they need them."

Platelets

Of particular importance over the holiday period are platelets, which play a vital role in the treatment of leukaemia and other cancer related illnesses.

Platelets only have a shelf life of five days, so it is imperative that blood stocks are constantly replenished.

Student nurse Rachel Walker, from Brough in Humberside, is one of 10 recipients of blood and blood products spearheading the campaign across the UK.

At 18 months old Rachel, was diagnosed with a rare blood disorder called Sideroblastic Anaemia.

This disorder stops the bone marrow from functioning properly.

From diagnosis, Rachel has needed constant blood transfusions to keep her alive.

She said: "It's the greatest gift I could ever receive. I've had the best life I could have ever hoped for and every second that they've spent giving blood has been worth it, and because I've had such a good life, they can take every second of that credit."

How it is used

Some 30% of blood products are used in accident and emergencies, 20% in general surgery, 15% in orthopaedic surgery, 10% in maternity and 25% in non-surgical use.

There are 4 main blood groups: O, A, B and AB. Group O is the most common and therefore the most in demand.

In the year April 2000 - March 2001 blood donors enabled the NBS to provide 2,910,104 units of blood and other products to 329 hospitals.

An average district general hospital will use between 550 - 750 units of blood a month. In a big hospital the figure can be as much as 2,500 units a month.

Donors who know they are unable to attend their next local blood donor session are urged to call the National Donor Help line on 0845 7 711711.