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Fact or Fiction?: It's No Tall Tale, Height Matters

Is it true that short people have a tougher time in life than their taller peers?
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©Janis Dreosti/istockphoto.com

Short people know the sad litany all too well: Numerous studies show that they probably earn less than taller colleagues. They get fewer dates as well as fewer promotions. Their bosses are probably taller than they are—in fact, more than half of U.S. CEOs clock reach six-feet- (183-centimeters-) plus. And if all that wasn't depressing enough, now comes word from Johns Hopkins University that height-advantaged Americans—particularly women—are also less likely to suffer from dementia.
   
So, as the song goes, do short people really have no reason to live, or is that a tall tale?

Height does not seem to be a prerequisite for greatness. Both Napoleon Bonaparte and Ludwig van Beethoven didn't make it to 67 inches (170 centimeters) tall. Mahatma Gandhi was even shorter. And the list of accomplished actors, musicians and other creative types who are short—defined as 57 inches (145 centimeters) for an 18-year-old boy and 56 inches (142 centimeters) for his female counterpart—is long.

But, as the Johns Hopkins study indicates, these sad short stories aren't just urban myths. Many are backed up by scientific research. Usually, the explanation goes back to childhood nutrition, especially during the first two years of life, says Tina Huang, the study's lead author, a researcher at Tufts University's Jean Mayer USDA Human Nutrition Research Center on Aging. Starved of adequate food, neither brain nor body develops appropriately.

Huang's study, published recently in Neurology, analyzed cognitive data, floor-to-knee measurements, and arm span measurements—an indicator of the maximum height likely to be achieved—of 1,145 men and 1,653 women in four cities across the U.S. from 1992 to 1999. The researchers found that each one-inch (2.5-centimeter) increase in knee height cuts a woman's risk of developing dementia by 16 percent (and Alzheimer's disease, in particular, by 22 percent). For each one-inch increase in arm span, the figures were 7 percent and 10 percent, respectively. Men showed a similar, if smaller, advantage. Huang admits she's not sure of the reason for the gender difference but speculates that "maybe there's a difference in optimal diet between men and women."

The study also found that the longer-limbed participants enjoyed "more years of education, increasing satisfaction with one's health," and, especially for women, higher income, thanks again to that early childhood nutrition, Huang says.

Diminutive people can find plenty of other scientific reading matter to make them feel—er—lower. A classic study by two University of Pittsburgh professors in 1990, for instance, reported that people in management positions were "significantly" taller than their underlings. In the 46 presidential elections where the height of both candidates is known, the taller contender won 27 times—a pattern that was repeated this November when the six-foot-one-inch (185-centimeter) Barack Obama defeated the five-foot-seven-inch (170-centimeter) John McCain.

Even a late growth spurt may not help. In 2004 two economics professors from the University of Pennsylvania and another from the University of Michigan at Ann Arbor analyzed height and salary data at various ages for about 10,000 American and British men born between 1958 and 1965. Using a regression analysis, they discovered that if two adults were the same height, the one who was taller as a teenager earned more—about 1.5 percent to 2 percent more per inch.

In this case, Daniel Silverman of Michigan, one of the report's authors, doesn't blame nutrition. Rather, he blames high school clubs.

"We see some evidence that these [taller] folk have access to social activities as teenagers that shorter kids didn't, where you might obtain social skills," Silverman says, citing student government, sports teams and yearbook staff.

So, should shorter people harbor any high hopes?

"There are a lot of different things that you can do in your life that make you less vulnerable to dementia and Alzheimer's"—such as a healthy diet, exercise, social interactions and continual mental challenges—"regardless of how tall you are," Huang says.

Also, some shorter people possess a rare genetic mutation, known as the "Methuselah gene," that seems to extend their life spans. This defect affects the way their cells use the hormone insulinlike growth factor 1. IGF1 plays a key role in childhood growth—and, more controversially, is touted by athletes and anti-aging proponents as a miracle cure that can help bulk up muscle, inhibit programmed cell death, and reduce body fat.

And smaller women have known since 1995 that they have a medical advantage in one area: According to a study published in The New England Journal of Medicine, older "women who were tall when they were young have a greater risk of hip fracture." Why? As the study astutely suggests, "perhaps because they fall further."

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