Left-handed and longevity

Experts have reevaluated the hypothesis that right-handed people must live longer than left-handed people.

>>>The fun of left-handed people

A commonly cited statistic suggests that right-handed people must live longer than 9 years on average compared to left-handed people. The origin of this argument comes from two reports in the late 1980s and early 1990s by psychologists Diane Halpern and Stanley Coren, posted on the Nature and New England Journal of Medicine journals. However, the above conclusion is facing a suspicious view of today's experts.

'The figure is not completely reliable' , BBC quoted Professor Chris McManus of University College London and author of Right Hand and Left Hand . He argues that if that is true, this is the largest "single predictor tool" on human life. It is the same as a person who smokes 120 cigarettes a day and at the same time does enough other dangerous things to health. According to expert McManus, the authors of the studies committed a "very unrecognizable mistake". These studies were conducted in southern California, where names of dead people are often made public. Expert Halpern and Coren took a list of people who had just died and contacted their families, questioning people who were too right-handed or left-handed. From 2,000 cases, they found that the average age of left-handed people was 9 years lower than right-handed people. Based on this data, they concluded that left-handed people tend to die young compared to right-handed people.

Barack Obama is the third left-handed US president since Ronald Reagan - (Photo: White House)

At first glance, everything seems very convincing. So what did the researchers do wrong? Professor Chris McManus points out that the mistake here is that they only observe deaths without taking into account those living. In fact, the number of people who are left-handed is more than the statistics in the report. It means that on the general level, the left-handed person is younger than the right-handed person, at least at the time of the study being published.'The ratio of left-handed population is about 10 to 11%, but this figure is artificially lowered during the period of Queen Victoria reigning in England' , according to Chris McManus. Not only is the left-handed person less welcome in the time from 1800 to 1900, but also because of their rather difficult life, making the opinion more and more attention to the point that they consider unusual. 'They work in factories, forced to use machines that are designed for right-handed people; Of course, left-handed people look awfully weird when working on this line , 'the expert explained.

Excessive attention, and may face the stigma of the people around, make the left-handed person cower, and try to force himself to use his right hand, from sitting on a school chair. Therefore, it is possible that some people in California's death list are left-handed but spend most of their lives under right-handedness. The conclusion here is that left-handedness causes people to lose their longevity, it is a fantasy. As for the risk of using the right-hand tool, that could happen. 'There is some evidence that left-handed people are more likely to suffer minor accidents' , according to Chris McManus. But he also said the risk of death in this direction was extremely low, and did not affect much to the overall mortality rate of left-handed people.