Donating blood - the facts

17 to 70-year-olds can donate You must weigh at least 7st 12lbs (50kg) You will be asked a few questions about your health A drop of blood will be taken to test for anaemia The blood is then taken, just less than a pint in no more than 10 minutes

By keeping the issue of donating in the spotlight, there is enough supply, but only just.

The service's advertising campaigns aim to be innovative and eye-catching and reach the country's five million-strong population, however there are challenges.

It has a publicity budget which is virtually non-existent.

And its chief outlets consist of free plugs on NHS ambulances, plus air time on TV news reports and column inches in newspapers.

However, a pre-Christmas push proved effective and new donors came forward.

They were inspired to act when they saw a thriving nine-month-old Robert Boyd.

Three teaspoons

With the permission of his parents, Mags and Robert, he became the face of that media campaign.

Mr Boyd said: "When our son was born he weighed only 1lb 9oz and required more than 20 blood transfusions."

Just three spoons of blood could save a premature baby's life

To save baby Robert's life it took very little blood - the equivalent of three teaspoons per transfusion.

But astonishingly 40 donors, giving about a pint of blood each, may be required following one road traffic accident and a leukaemia patient may require 100 donations during their course of treatment.

Moira Eadie, donor services manager with the Scottish National Blood Transfusion Service, explained why it was especially important to continue campaiging at Christmas.

She said: "It is imperative that the service launch publicity campaigns during times of the year where potential donors may break from routine and become busy with other activities.

Uphill battle

"At Christmas, for example, people fail to donate due to Christmas shopping, office parties or bad weather - and supplies can become dangerously low."

Moira Eadie: "People fail to donate at Christmas"

So the battle is often an uphill one - 1,000 donations are needed every day in Scotland to maintain blood stocks.

Moira added: " Patient testimonials capture the public interest by reminding them that their donation will make a difference in meeting the needs of Scottish patients.

"This was illustrated to a great effect by Robert Boyd."

Celebrities also attract the public eye.

And they were being enlisted on 27 December to help in the next drive for donors.

More donors giving more often means more blood available for patients who need it.

Scottish National Blood Transfusion Service spokesperson

It is titled the "Three Times Promise" and mirrors last year's campaign to encourage past donors to give more often.

If you are healthy and willing you can donate blood at least three times a year.

A service spokesperson said: "More donors giving more often means more blood available for patients who need it.

17,000 extra donations

"At the moment donors give blood on average 1.6 times a year. If we could raise that to 1.7 then we would have an extra 17,000 donations going into the blood bank every year."

The majority of adults will be able to give, however, there are a few notable exceptions.

A little less than one pint of blood is taken in a donation

Not surprisingly if you have a cold or are on antibiotics you will not be allowed to donate.

If you have had hepatitis, jaundice, acupuncture, ear or body piercing, tattoos or a blood transfusion within the last 12 months you will not be eligible.

You will also be unable to donate if you are pregnant or have had a child within the last 12 months.

But the service said there are thousands of Scots who are eligible now and able to join the 250,000 who are already giving.

Despite all the publicity, just 5% of the UK's population gives blood - yet 100% of the UK's population could one day need blood.

There is a long way to go before the service enters that comfort zone, however, it knows the constant drip drip of publicity will yield results and keep supplies in the bloodbank.