What's With All the Nearsighted People? (The Atlantic)
Over the past 15 years, the world has witnessed an explosion of cases of myopia, or nearsightedness. A quarter of the world's population, or 1.6 billion people, now suffer from some form of myopia, according to the Myopia Institute. If unchecked, those numbers are estimated to reach one-third of the world's population by 2020. While myopia has always affected a fraction of the population, at least in countries that have kept records, the condition has recently reached unprecented rates among children and young adults.
A National Institutes of Health study published in 2009 showed that myopia prevalence in the United States increased by 66 percent between the early 1970’s and the early 2000’s.
The number of people in the world who are obese or overweight has topped 2.1 billion, up from 875 million in 1980, the latest figures published in the Lancet show.Global population of obese and overweight tops 2.1bn (BBC)
And not one country is succeeding in treating it, said the research.
US, China and Russia had the highest rates and the UK was third in Western Europe, the 188-country study said.
Experts said the rise was due to the "modernisation of our world", causing "physical inactivity on all levels".
Using fossil records to measure cranial capacity through the millennia, researchers have found that as we become increasingly domesticated as a species, the size of our brain continues to shrink. Bruce Hood, psychologist at the University of Bristol, UK, says shrinkage is best explained by changes in society: "We have been self-domesticating through the invention of culture and practices that ensure that we can live together." Hood notes that as humans have domesticated other species, from cows to dogs, their cranial capacity has also shrunk as they learn to enlist the help of their human masters rather than invent their own solutions.Human Brain Size Is Shrinking. Thank Domesticity. (Big Think)