Do right-handed people live longer than left-handed people do? There are many factors at play here, not least the prejudice against the left-handed. Left-handed children are forced to use the right hand because right-handed people think that being left-handed is abnormal. The Latin word for left-handedness originates from sinstra, meaning unlucky or evil. A Catholic teacher told one left-handed six-year-old that she was the Devil’s child. Myths and fallacies abound about handedness. Many people believe that left-handed people do not live as long as right-handed people, that they have more cancer, heart and blood-vessel disease and that they have more accidents. On the good side, people also believe that left-handed people are more artistic and that they are better at sport.
Although scientists know much about how humans develop in the womb and after birth, factors dictating handedness are still unknown. Scientists still cannot find a gene or gene cluster that dictates handedness. They think that there may be a connection between genetics and environment, which encourages a child to favour one hand over the other. Left-handedness tends to run in families.
Ideas that left-handed people do not live as long as right-handed people originate from the fact that, as the population ages, the numbers of left-handed people fall. 10-15 percent of teenagers are left-handed,;among people aged 50, 5 percent favour the left hand, and there are only 1 percent left-handed people among 80-year-olds.
Whilst many people take the simplistic view that this is because left-handed people die, there may well be other factors explaining this apparent lack of left-handed people in the population. People over forty may not describe themselves as left-handed because they are embarrassed, having suffered prejudice, stigma, or were forced to change hands as children. It was once common for teachers to force children to use the right hand.
Many research studies show that left-handed people die earlier than right-handed people do; however, for the most part these are older studies. Studies undertaken more recently give mixed results. A research study, undertaken in Denmark, on twins, in which each pair had one left-handed twin and one right-handed twin, found no difference in death rates. Another found that, among left-handed American baseball players, left-handed players did not die much earlier than their right-handed counterparts did. One large study concentrated on 39,600 women aged 55-69 and, after adjusting for factors such as smoking, weight, body fat etc., whether women were left-handed, right-handed or ambidextrous was insignificant.
However, a conflicting study found that there were more left-handed elderly patients in a cardiac unit than in the general population, which would appear to show that left-handed people are more likely to suffer heart disease. The older studies cannot be ignored, but, at the very least, there is conflicting research on the matter and the jury is still out.
It may be that, just as older people may be unwilling to describe themselves as left-handed from shame, it could also be that older researchers are unconsciously partial because of the old stigma associated with those who are left-handed. It could be that left-handed people find it difficult to live in a right-handed world. Two US studies appear to show that left-handed students and left-handed Californian residents have more accidents than their right-handed counterparts do. In both cases, the researchers concluded that this was because tools and cars are made for right-handed people.
One cannot say definitely that left-handed people have shorter life spans than right-handed people do, because research studies show conflicting results, and it is uncertain why left-handed people form a smaller portion of the older population. More research is required before anyone can say definitely what determines handedness and whether or not right-handed people live significantly longer than left-handed people do.
It may be that being left-handed is natural. Cave paintings painted between 30,000 and 10,000 years ago indicate that 23 percent of our ancestors were left-handed, and scientists conclude that being left-handed may have given left-handed people an advantage when fighting. Scientists know that there are several factors working in determining whether a child is right- or left-handed; they have not yet discovered exactly how far genetics plays a role. Current research studies show conflicting results.Until there are more research on unravelling the human genome and more comprehensive research studies, nobody can say that the perceived tendency for left-handed people to die earlier than their right-handed counterparts even exists, or, if there is a difference, what factors truly cause that difference.