Has the 20th century been good for our health? Of course it has, you say. Vaccines, antibiotics and improved living conditions have tamed such killers such as smallpox and diphtheria. Infant mortality has dropped steadily since the early 1900s, as has women's risk of dying in childbirth. Deaths from stomach cancer have fallen by 90 percent since the 1930s, when we started using refrigerators instead of salt and smoke to preserve food. And since the advent of the Pap smear, deaths from cervical cancer have fallenby 75 percent. Together these achievements have had a huge impact on the length and quality of our lives. Average life expectancy, just 47 years for a child born at the turn of the century, now stands at 74 years for males and 79 years for females.
If only that were the whole story. The irony is that the comforts we've attained during the 20th century have spawned a new generation of health hazards. "What we've done," says Dr. William Dietz of the Centers for Disease Control and Prevention (CDC), "is replace the diseases of deficiency with diseases of excess." Blessed with cheap, abundant food and an economy that values brain power over back strength, Americans are growing fatter and more sedentary. The effects are not merely cosmetic; our way of life fosters an array of deadly ills, from hypertension and heart disease to diabetes and some cancers. Yet, as an extensive new health survey makes clear, we've hardly begun to confront what is happening to us.
The survey was commissioned by Discovery Health Media to launch its new Discovery Health Channel, and was conducted in conjunction with NEWSWEEK. During June, the polling firm Penn Schoen & Berland questioned 1,200 U.S. adults about everything from their sex and smoking habits to their diets, their exercise patterns and their knowledge of health and disease. The news is not all bad; nearly everyone now recognizes the importance of exercising, eating vegetables and going easy on salt, sugar and fat. But the findings show significant gaps in our knowledge (four in 10 men don't know that 220 is an unhealthy cholesterol level; four in 10 women haven't heard that folic acid can help prevent birth defects). Worse yet, the poll results suggest that what we know has very little effect on how we live.
Consider the findings on diet. Though 91 percent of the respondents agree that eating five servings of fruits and vegetables each day is "important to maintaining a healthy lifestyle," more than a third eat just two servings. And while 92 percent believe it takes two servings of milk, yogurt or cheese each day to meet the body's need for calcium, roughly four in 10 eat less than that. Only 13 percent of those polled say they eat six servings of grain each day, even though most think it's important. And while 83 percent agree that we should "limit sugar and fatty foods to one serving per day," majorities of both men and women say they exceed that threshold. You might guess that we're cutting back on those foods, even if we still overdo them, but government data suggest just the opposite. Per capita consumption of fats, oils and sweeteners has nearly doubled since the early part of the century (chart)--and we're guzzling nearly five times as much soda as we did in 1947.
If we spent our days wrestling alligators, we'd have more use for the calories in those colas, chips and candy bars. But we're burning less energy than ever. Most respondents to the Discovery/NEWSWEEK survey say they exercise regularly, but few do anything more vigorous than walking--and even that gentle pastime is in decline. Federal surveys suggest that Americans walk 15 percent less today than we did 20 years ago. Cars now account for 85 percent of the travel within U.S. cities (versus 45 percent in the Netherlands). "We used to at least get out of the car to open the garage door," says Michael Goran, an obesity researcher at the University of Alabama in Birmingham. "Today we push a button." We also spend ever-greater stretches of our days glued to televisions and computers. A new study from the University of Pennsylvania's Annenberg Public Policy Center finds that American kids (ages 2 to 17) now average 4.4 hours of screen time every day--up from 4.1 hours a year ago. And the proportion of high-school students taking a daily gym class dropped from 42 percent in 1991 to just 27 percent in 1997.
The consequences shouldn't surprise us. Studies show that more than half of the nation's adults are either moderately or morbidly overweight (a finding confirmed by this survey)--as are 25 percent of children. Our growing girth has begun forcing managers of ballparks, concert halls and movie theaters to replace traditional 18-inch seats with wider ones. Commercial airlines (for which narrow seats are a point of principle) are raising the pull-down trays on new planes to create more belly room. And doctors are learning to monitor young people for what we once considered diseases of old age. "Ten years ago we were teaching medical students that type 2 diabetes doesn't occur in people under 40," says Dr. Robin Goland of New York's Columbia-Presbyterian Hospital. "Now we're finding it in teenagers." Those cases are still fairly rare, but they're growing more common every year. Recent studies suggest that 16 to 20 percent of young diabetics are now diagnosed with type 2 disease, up from 3 percent in the early 1980s. "The concept of 30-year-olds losing their legs and going blind from type 2 diabetes is amazing," Goland says. "The good news is that this disease is preventable."
But only if you're determined to prevent it. Among the Discovery/NEWSWEEK poll respondents who say they're overweight, fewer than half are dealing actively with the problem. Only 42 percent are trying or even planning to improve their diets; only one in five is practicing or considering a structured exercise program. The proportion of people actually taking those steps is lower still--and declining. According to CDC studies, the proportion of overweight men engaged in sound weight-loss practices fell from 25 percent in 1985 to 15 percent in 1995. The rate among women dropped from 30 percent to 19 percent.
We are doing a few things right. Though Americans still lag in fruit-and-vegetable consumption, we're eating more of them than ever before. And the percentage of our calories derived from fat (especially animal fat) has fallen slightly. That may help explain why heart disease, though still our No. 1 killer, is declining. Will that progress continue? We know where the challenges lie, and most of us know how to meet them. The problem isn't that we lack information but that we live in a world where overeating is easy and exercise is optional. The question is whether we can muster the will to live differently.