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It does not seem to have held back Sir Paul McCartney, David Cameron or Barack Obama - but research suggests people who are left-handed are likely to earn 12 per cent less over their lifetime.

A study of 47,000 people in the UK and US indicates that left-handers are at a significant disadvantage in the workplace.

The research seems to dispel the myth that 'lefties' are more likely to be gifted than their peers.  

A study of 47,000 people in the UK and US indicates that left-handers are at a significant disadvantage in the workplace and earn 12% less over the course of a lifetime. One in eight people favour their left hand over their right, and the research seems to dispel the myth that 'lefties' are more likely to be gifted than their peers

One in eight people favour their left hand over their right.

Professor Joshua Goodman, an economist at Harvard, Massachusetts, in fact suggests that those who write with their left hand live with many disadvantages.

Writing in the Journal of Economic Perspectives, he wrote: 'Lefties exhibit economically and statistically significant human capital deficits relative to righties.

'Left-handed individuals show consistently lower cognitive skills and higher rates of mental and behavioural disabilities.

'This paper is the first to demonstrate that lefties also have consistently lower labour market earnings than right-handed individuals.'

The gap in earnings he reveals is the equivalent to that found by those leaving school a year earlier, Professor Goodman found.

He argues that this is still true even when you take into account factors like infant health and the subject's family background.

The reasons for the earnings disparity are unclear - but the economist suggests that people who are left-handed may be at a fundamental cognitive disadvantage.

The data suggests left-handed children are three percentage points more likely to be in the bottom tenth of exam scores than right-handers.

And they are more likely to have learning disabilities or dyslexia.

The professor said that left-handedness has long been viewed with suspicion.

'During the Middle Ages, left-handed writers were thought to be possessed by the Devil, generating the modern sense of the word sinister from sinistra, the Latin word for left,' he said.

'The English word left itself comes from the Old English lyft, meaning idle, weak, or useless. The French word for left, gauche, also means clumsy or awkward.'

The popular perception that left-handers are more gifted came later, he said, encouraged by anecdotal evidence including the fact that four of the last seven US presidents have been left-handed.

He suggests that what he sees as a clear cognitive deficit is down to the wiring of the brain.

The way the brain works is fundamentally connected with 'hemispheric bias' - the way different functions are associated with the left or right side of the brain.

Some scientists believe the choice to use the left hand over the right is influenced by the way this hemispheric bias developed in the womb, when the fundamental structures of the brain were first formed.

The reasons for the disparity are unclear - but the economist suggests left-handed people may be at a cognitive disadvantage. His data suggests left-handed children are three percentage points more likely to be in the bottom tenth of exam scores, and are more likely to have learning disabilities than right-handed peers

Professor Goodman claims to have found a correlation between left-hand preference and low-birth rate, which would appear to suggest that left-handers are more likely to have suffered trauma or stress in the womb.

Other theories he puts forward is that left-handedness is genetic.

His study found that left-handers whose mother was also left handed do not suffer from lower cognitive ability.

But right-handed children of left-handed mothers also appear to have 'cognitive deficits', suggesting it is the change or mismatch with parents that leads to a problem.

In a separate blog, Professor Goodman wrote: 'In other words, mismatch between the handedness of parents and kids may be as important as handedness itself.'

The reason might be that children find it harder to mimic their mother – a key learning tool - when she is using the opposite hand.