From being accused as being witches or possessed with unclean spirits, lefties have certainly come a long way. I remember having a classmate who was constantly whipped for not using his right hand to write or do any other thing. The cultural bias doesn’t help matters either. In Yorubaland, it’s considered disrespectful to hand things over to elder ones using the left hand. Today, it’s very much better than it used to be. We’ve come to accept this 10% of the world’s population for who they really are. Today, it’s even become an ability others admire, coupled with the general perception that left handed individuals have special abilities. Well, it’s not a proven theory yet. However, it hasn’t been disproved either. Why do people emerge left-handed?
Well, we don’t know for sure. There’s the part of genetics we can point to because twin studies have shown that about 25% of handedness can be attributed to inheritance. There’s also an aspect of environmental pressures in form of societal and external cultural pressures. These theories can also explain the presence of right-handed children in families with left-handed parents and vice versa. However, that’s about that for all we know about why some people are left-handed. For the purpose of emphasis, it must be said that being left-handed is not a feature that any stigma should be attached to in any form. No parent or teacher needs to flog a child into a compulsory use of the right hand. For what it’s worth, it might interest you to know that Barack Obama, the first black American president is left-handed. The world’s most powerful individual sometime not too long ago was left-handed. All of that being said, let’s focus on the topic at hand.
Studies to find the reasons for disparities in handedness have also helped to shine light on a number of conditions that may have increased risk component in people who use a particular hand. Left-handed people may have increased risk for some health conditions and decreased risk for some. A 2007 study published in the British Journal of Cancer examined hand preference and cancer risk and suggested that women with a dominant left hand have a higher risk of being diagnosed with breast cancer than women with a dominant right hand. Another 2011 study suggests that left handers have significantly higher chances of developing periodic limb movement disorder (PLMD) which is characterized by involuntary, repetitive limb movements during sleep. When studying patients with psychotic disorders, such as schizophrenia and schizoaffective disorder, 40 percent of the patients reported writing with their left hand. Left-handed people may be at more risk for PTSD and alcohol consumption. For children of school age, more learning disabilities, behavioural and emotional problems may be found.
Left-handed people may actually have reduced risk for ulcers and arthritis. Thy may also have faster stroke recovery.