As a child, the parental mantra was “Eat your vegetables. They’ll make you big and strong,” which seemed reasonably plausible. It was something you could swallow with a grain of salt, and a milkshake.
Turns out, though, your eating (and lifestyle) habits in adulthood may influence your height as well. Or more specifically, how long you remain “long.”
A massive longitudinal study of 17,708 adults (beginning at age 45) by researchers at the University of Southern California found that healthy habits in later years influence the rate of shrinkage in those later years.
For younger study participants who had not yet begun the inevitable shrinking with age, it was easy for scientists to accurately measure height. For older participants, the researchers compared the relationship between current height and length of limbs, which do not shrink with age.
They found a strong relationship between height loss and indicators of adult health, not least among them cognitive skills. Participants who had lost more height more rapidly over time were also more likely to perform poorly on standard tests of cognition, such as short-term memory, basic arithmetic and awareness of the date.
Urban dwellers lost less height in adulthood than did rural residents. Education was also a key measure. The more schooling, the less height loss. Completing high school, for example, translated into one less centimeter of shrinkage over time.
“Height has been recognized as an acceptable proxy for childhood health conditions, but there are complications there,” said economist and co-investigator Geert Ridder. “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.”