Education And Wealth Keep Adults From Shrinking
It is known how nutrition and health as a child impacts how tall someone can become and we take it for granted that as we age we lose a couple of inches of height from our peak. But a new study finds that a healthy lifestyle can have an important impact on how much shorter you get.
Researchers have looked through data covering 17,708 adults, beginning when they were 45, from all across China at a time when health care and access to better standards of living have entered the picture. Among one of the many findings, came interesting results linking height loss and cognitive health.
"Had we only examined the correlations between measured height and health, we would have missed this important insight," says John Strauss, professor of economics at the University of Southern California. "The evidence shows that it is not only early-life events that are associated with how we age, but health decisions in later life as well."
Researchers found that urban dwellers had less height loss than those from rural areas, during a time where China has seen significant migration towards cities. Having completed primary school and being literate was associated with 0.9 cm less loss of height in men. This is almost one third the 3.3 cm average height loss in men over 45. Those that completed high school had close to 66 percent less height loss having been spared losing 1.9 cm.
Similar results were seen in women where those that finished primary school had a benefit of not losing 0.6 cm out of an average of 3.8 cm.
Researchers used many metrics to measure height loss and compounding factors, such as scoring overall health, education and socioeconomic status. Researchers handed out surveys, performed blood tests, analyzed health records, looked at the height of older and younger participants and compared those results to the length of limbs (which do not change as people age and shrink).
Interestingly, those that showed the most shrinkage in old age were more likely to perform worse on standard tests of cognitive health which included examinations of short term memory, basic arithmetic and awareness of the date.
Researchers will follow participants every two years and capture valuable data in a rapidly aging population in the most populated country on the planet. Additionally, the data will be helpful in determining the value of instituting healthcare systems in benefiting the health of the elderly.
The research published in the American Economic Journal: Applied Economics can be found here.