Being short isn't easy. Short people make less money, have a harder time finding a mate, and are less likely to be elected to public office, statistics show.

A new study suggests that it gets worse: The shortest short people -- men under 5 feet 5 inches and women under 5 feet -- are roughly 50 percent more likely than the tallest people to have a heart attack or die from heart disease, according to an analysis published in the European Heart Journal.

Why? Probably due to a combination of underlying factors that contribute to both short stature and poor heart health, such as age, the researchers say. "Older people are shorter," the lead author of the study, Dr. Tuula Paajanen, M.D., a researcher at the University of Tampere, in Finland, points out in an e-mail. "Also, you have to remember that height is at least a combination of genetics, socioeconomic status, and nutritional factors. So when using height we are also thinking about some confounding factors."

Paajanen and her colleagues analyzed data from 52 high-quality studies that included more than 3 million people. Hundreds of studies dating back to 1951 have explored the link between short height and heart disease, but this is the first systematic review and analysis of all the good studies on the subject. The findings are hardly proof that being short puts you at greater risk of heart disease, says Dr. Michael Lauer, M.D., the director of the division of cardiovascular sciences at the National Heart, Lung, and Blood Institute.

The study's "major limitation is a failure to take into account confounding factors," he says. "It's much easier to measure somebody's height than it is to measure lots of other environmental factors that could affect height." Nutrition is the most important environmental factor that influences both height and heart health, Lauer adds, but everything from air pollution to employment status to hydration could play a role.

Poor nutrition early in life can have far-reaching effects that last well into adulthood, Mr. Jaako Tuomilehto, M.D., a professor in the department of public health at the University of Helsinki, in Finland, notes in an editorial accompanying Paajanen's study.

Children who aren't properly nourished shortly after birth -- or even in the womb -- tend to grow more slowly than their healthier peers, Tuomilehto explains. And as they gain weight rapidly to "catch up" with their peers, they often accumulate excess body fat, which can lead to heart disease down the road.

Though she acknowledges the study's limitations, Paajanen says that doctors may want to consider height when judging a patient's risk of heart disease. The findings should also encourage short people to take their heart health more seriously, she says.

"People have no control over their height or genetics, [but] they can control their weight and lifestyle habits such as smoking, drinking, and exercise," she says. "All of these together affect heart disease risk. The more risk factors you have, the more effort you should concentrate to reduce the risk factors you can."

Doctors and patients should focus on the heart disease risk factors they can control, Lauer agrees.

"We should be interested in modifiable factors that are related to disease and that we can do something about -- poor nutrition, lack of exercise, cigarette smoking," he says. "We can't do anything about height."