Apart from being responsible, sensible, balanced and other characteristics associated with first born children, science now says that they are also more likely to be myopic, or nearsighted.
90,000 adults between the ages of 40 and 69 were part of a study which has found that first-borns were approximately 10 percent more likely than their younger siblings to be myopic, and 20 percent more likely to have high myopia. The study was published in JAMA Ophthalmology.
Myopia affects up to one in three people in the UK, and normally develops during adolescence. The condition can be rectified using by glasses, contact lenses or surgery, reports The Guardian.
The authors of the study have suggested that the reason for near sightedness is the child's education. "My assumption is that individuals who go on to spend more years in full-time education spend relatively less time outdoors and relatively more time in tasks such as reading during their childhood," Jeremy A. Gugenhenheim, PhD, of Cardiff University, told TIME.
Gugenhenheim had initially thought that the relationship between birth order and myopia would be related to birth weight, but was surprised when education factored in.
"Our original hypothesis was that it would be related to the tendency for first-born children to be a little lighter at birth than average. To be honest, the relationship with birth order interested us because it seemed a little quirky," Guggenheim said, according to TIME.
Myopia is on the rise in other countries also. In China, four in every five teenagers is short-sighted. A study in the U.S., which tracked 500 school children over a period of five years, reported that 20 percent of the children were diagnosed with myopia, according to the Daily Mail.
