As people are busy racing around getting ready for Christmas, the last thing to come to mind is the thought of giving blood.

But the demand is always there. The National Blood Service (NBS) says the more people who come forward, the more lives can be saved.

Three-year-old Fern Britnell is one person who would not be alive today if it wasn't for the donations people have given.

The youngster from Burgess Hill, who suffers from a severe form of anaemia, has already had more than 30 blood transfusions in her young life and is likely to need many more in the future.

Her parents say they are extremely grateful for the help people have given and are actively campaigning to encourage more people to come forward and give blood.

Hilary Marks, from Brighton, lost two pints of blood following an accident at home, which severed an artery in her arm.

She said: "Obviously, doctors needed to give me blood as soon as I arrived.

After I recovered, I wanted to do my bit to help others which is why I started to donate blood.

"When you go into hospital, you always take for granted that the blood will be there but I was quite shocked at how low levels can go."

Blood comes in four main types O, A, B and AB. Group O+ is the most common blood type, which means it is in demand.

The rarer Group O-, which is carried by about seven per cent of the population, population, is even more in demand since it can be given to any patient, regardless of his or her blood type.

About 23 per cent of donated blood is used for general surgery and 13 per cent for heart and chest surgery.

Other areas include orthopaedics, blood diseases, accident and emergency, intensive care and gynaecology.

If a person has surgery, he or she may lose some blood during the operation. If this is a small amount, the fluid can be replaced with a salt or glucose solution.

The body will then make new red cells over the next few weeks. If a person loses a significant amount of blood, doctors will want to replace it as quickly as possible, so they do not suffer the weakening effects of blood loss.

The NBS says winter is a challenging time for blood collection as colds and flu sweep across the region and the days get shorter. Attendance at sessions in Sussex can fall by as much as ten per cent and yet the demand for blood never stops.

Of particular importance at this time of year are platelets. Platelets only have a five-day lifespan, so it is vital donors come forward during the holiday period.

Platelets are a component of blood and are frequently needed by cancer patients who have undergone chemotherapy.

The NBS says because blood can only be kept in storage for a relatively short period of time, the turnover has to be constant and frequent, otherwise, blood banks will run out of stocks quickly.

NBS spokesman Russell Guthrie said: "Holiday periods are often difficult periods for the NBS. When everyone else is winding down, the NBS must step up a gear in order to get blood stocks up to a sufficient level to cover the holiday period."

In 2000, Royal Sussex County Hospital in Brighton, needed 12,840 red cell units and 590 platelets.

For Eastbourne District General Hospital the figure was 10,315 red cell units and 959 platelets. Worthing Hospital required 9,363 red cell units and 777 platelets and Crawley Hospital needed 4,871 red cell units and 581 platelets.

If you are aged between 17 and 60 (17 and 70 for regular donors), you can probably give blood and help ensure all the patients in hospitals get the treatments they need.

For more information, contact the NBS National Helpline on 0845 7711 711, or go to