April 1, 2013
Height Changes In Life Linked To Lifestyle Decisions
Lee Rannals for redOrbit.com — Your Universe Online
A group of economists have found healthy habits influence how much you shrink as you grow older.
Economists from the University of Southern California, Harvard University and Peking University used data from a survey of 17,708 adults beginning at age 45 and showed how lifestyle choices in adulthood influence how tall we stand as we age.
"Had we only examined the correlations between measured height and health, we would have missed this important insight," said John Strauss, professor of economics at USC, and an investigator on a study published in the April 2013 issue of the American Economic Journal: Applied Economics. "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."
The researchers are the first to examine height loss as we age, showing that regardless of your maximum height, the loss of height over time is an important indicator for other health issues.
Participants in the study who lost more height were also more likely to perform poorly on standard tests of cognitive health like short-term memory, ability to perform basic arithmetic and awareness of the date.
The researchers also found urban dwellers had much less height loss than those in rural areas.
"Height has been recognized as an acceptable proxy for childhood health conditions, but there are complications there," says USC economist Geert Ridder, a co-investigator on the study. "Some of adult health might be determined by childhood circumstances, but people shrink differentially, and that shrinkage is also a measure of adult health conditions."
Humans go through many different physical changes with age, including an increase in body fat and decrease in bone mass. However, a decrease in height can be further exacerbated by certain kinds of arthritis, inflammation of spine joints or osteoporosis.
They also found a link between education and height shrinkage. Those who were able to complete high school versus those who only completed primary school saw less shrinkage. Part of this could be connected with a link researchers reported in Public Health Nutrition last week between education and better nutrition.
Researchers reported parents with a lower level of education feed their children foods rich in sugars and fats more often than parents with a higher level of education.