WASHINGTON: Are you a leftie or a righty? The duration for which a child is breastfed may determine handedness or the dominant hand, says a research.
Infants who are bottle-fed are more likely to be left handed than those who are breastfed, scientists from University of Washington claim.
The study of 60,000 mother-infant pairs found that the prevalence of left-handedness is lower among breastfed infants as compared to bottlefed infants.The study, from the University of Washington, suggests that the prevalence of left-handedness is lower among breastfed infants.
The findings, published in ‘Laterality: Asymmetries of Body, Brain and Cognition’, showed that breastfeeding for less than one month, one to six months, and more than six months, when compared to bottle feeding, was associated with a 9%, 15%and 22% decreased prevalence of non righthandedness, respectively.
“We think breastfeeding optimises the process the brain undergoes when solidifying handedness,” said Philippe Hujoel, a professor at University of Washington.
“That’s important because it provides an independent line of evidence that breastfeeding may need to last six to nine months,” said Hujoel.
The study does not imply, however, that breastfeeding leads to right-handedness, Hujoel said. Handedness, whether it be right- or lefthanded, is set early in foetal life and is at least partially determined by genetics.
The research sheds light on when the region of the brain that controls handedness localises to one side of the brain, a process known as brain lateralisation. It shows, breastfeeding optimises this lateralisation towards becoming right- or left-handed.