Here’s Why Oldest Children Are More Likely to Be Nearsighted

If you’re an oldest child, stereotypes suggest you’re probably organized, an overachiever, perhaps a tad bossy. And now, science suggests you’re probably also more nearsighted than your younger siblings, too. A study published Thursday in JAMA Ophthalmology used data from the British Biobank longitudinal survey to get information from nearly 90,000 adults between the ages of 40 and 69. They combined demographic data with behavioral information—one question asked how much time people spent outdoors, for instance—along with a detailed educational history and their ophthalmological past. Jeremy Guggenheim, a professor of optometry and vision sciences at Cardiff University’s Eye Clinic and lead author of the paper, found that firstborns were 10% more likely to develop nearsightedness and 20% more likely to show signs of severe nearsightedness, even after Guggenheim and his colleagues adjusted for other factors. Younger siblings, on the other hand, were less likely on average to be myopic, and when they were, they had lower degrees of nearsightedness. Myopia—the scientific term for nearsightedness—is a growing concern in fast-developing countries like India and China, where rates of childhood nearsightedness have skyrocketed in the past couple of generations. The study authors suggest the reason for the nearsightedness has to do with a child’s education. Previous research has shown that parents are likely to invest heavily in t...
Source: TIME.com: Top Science and Health Stories - Category: Consumer Health News Authors: Tags: Uncategorized Britain Education investment myopia nearsightedness ophthalmology Parenting public health Research United Kingdom Source Type: news