- Researchers found that young adults are more likely to have a nail-like growth in the lower part of their skull that used to be extremely rare.
- They believe that the growth of an "external occipital protuberance" has become more common as we spend so much time on our phones.
- When we crush a screen, we put in place where the neck muscles meet the skull.
- The body can then develop extra layers of bone to cope with extra weight.
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Young adults are more likely to have nail-like growth on their skull, and a scientific study has linked the phenomenon to increased use of smartphones and tablets from a young age.
Growth, known as an external occipital protuberance, appears in the lower part of the skull and is becoming more common in young adults
The function used to be so rare that a French researcher named Paul Broca complained in 1
But a study published in the Journal of Anatomy found that growth became more common – especially among 18 to 30 year olds. About a quarter of the 18-30-year-olds in the study had an external occipital protuberance.
David Shahar, Australian health scientists who conducted the research, believes that the development was triggered by the modern obsession with smartphones.
When people brake over their screens, they put pressure on the neck muscles facing the skull, he told the BBC. The body then develops more bone layers in that area in order to keep extra weight.
Leaning forward during telephone use can cause "text throat"
The skull's protrusion can be particularly pronounced nowadays because of the large number of time that people spend on their phones, according to the BBC.
People also had posture problems before the explosion of smart devices, for example, when they read.
But the average American only read two hours a day in 1973. Last year, three and a half hours were spent daily on their phones in the United States.
Another surprise that Shahar encountered in his study was how great these growths were on the skull.
The most significant growth he found was 30mm long, he told the BBC. To compare, an Indian lab specializing in the legs wrote an entire report on an 8 mm long external occipital protuberance that it found in 2012.
Shahar believes the nails will continue to grow when people continue to skip their handheld devices. But growth itself should not be dangerous, he said.
"Imagine if you have stalactites and stalagmites, if no one interferes with them, they will only continue to grow," Shahar told the BBC.
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