Something is wrong, if not rotten, in the state of New York, the state of California and every state in between. While searching endlessly for just the right diet, we're consuming ever more calories, growing ever more obese and suffering obscene rates of diabetes, hypertension and heart disease as a result. No one outside the weight-loss industry is happy about the situation, but as the crisis worsens we seem to grow ever more confused about how we got here--and ever more polarized about how to set things right. Die-hard vegetarians continue to rail against dietary fat and emulate Chinese peasants. Born-again carnivores blame the White Devil (a.k.a. bread) and force themselves onto all-meat diets in hopes of incinerating their belly fat. Ordinary civilians throw up their hands and consume whatever is convenient--which is to say Krispy Kremes and Coke.
Is this the cost of modernity? Have we escaped scurvy, pellagra and rickets only to suffer higher-tech forms of malnutrition? Somewhere in the fog of conflicting prescriptions, is there a diet that's both safe and palatable--a diet that can control weight and promote health without denying us the pleasure of food?
The federal government has long tried to distill the best science on diet and health. But commercial pressures and bureaucratic obstacles have often clouded the results. The USDA's famous Food Guide Pyramid, first published in 1992, is now widely viewed as flawed. "The pyramid is a disaster," says K. Dun Gifford of Oldways, a nonprofit think tank based in Boston. "The American epidemic of obesity is the proof that it hasn't worked. Period. Amen."
That doesn't mean all such efforts are doomed. Researchers have gained critical insights into diet and health in recent years. And while they wait for the USDA to remodel its now crumbling pyramid, some of those experts are concocting whole new alternatives. By far the most ambitious of these efforts is the so-called Healthy Eating Pyramid devised by Dr. Walter Willett and his colleagues at the Harvard School of Public Health. Instead of simply pooling diet preferences, the Willett team claims to have distilled the best evidence from all possible data sources, including Harvard's huge Nurses' Health Study, Physicians' Health Study and Health Professionals' Follow-Up Study. The Healthy Eating Pyramid has some controversial features, including a strong endorsement of calorie-rich vegetable oils and a virtual prohibition of potatoes and white rice. But its health effects have been cleverly evaluated and affirmed. The diet is designed not for short-term weight loss but for lifelong health. It doesn't require that you weigh your food or eat according to your blood type or astrological sign. As Willett likes to say, its ultimate message is simple: "Eat, drink and be healthy."
The main difference between the Healthy Eating Pyramid and the government's plan is its focus on individual foods. Willett is quick to break up groups of fats or carbohydrates or proteins to highlight the best and worst sources of those nutrients. That may seem an obvious distinction, but it's a critical departure from the USDA's recommendations. Instead of directing people to the best fats, the most wholesome carbohydrates and the most nutritious sources of protein, the USDA pyramid implies that all fats are dangerous and most carbs are safe. And if the past decade has taught us anything, it's that carbs can be as deadly as fats.
How did the government get it so wrong? Basically by trying too hard to simplify its message. Scientists have known since the 1960s that the saturated fat in red meat and dairy products can raise cholesterol levels and promote coronary heart disease. Though the USDA had long downplayed those risks to appease the cattle and dairy industries, it had also acknowledged them. When the USDA staff started building the Food Guide Pyramid in the late 1980s, its main objective was to get that message out. Earlier food charts had shown four basic groups--meat, dairy, produce and cereal grains--and encouraged people to eat everything in moderation. The pyramid introduced the notion that some foods (fats) required more moderation than others (carbohydrates).
Scientists were well aware that fats could be healthful and that carbs could cause harm. Studies had shown that unlike butter and lard, the oils found in fish, nuts and vegetables helped protect against heart disease--and that cereal grains had all the nutritional value of table sugar when milled into flour. But instead of trying to convey these insights, the USDA focused on the situation at hand. Americans were getting most of their fat from meat and dairy products. The agency's advisers reasoned that any reduction in fat would mainly affect saturated fat. And if people replaced the lost meat with starch, at least they would lose some calories.
If the environment hadn't changed, the strategy might have worked. But food-makers soon discovered the potential of low-fat processed foods. Cereal grains aren't very profitable in raw form, notes Elizabeth Pivonka, president of the Produce for Better Health Foundation. "If you puff them, sweeten them and put them in a box with a picture on the front and a toy inside, you can charge a lot more." The pyramid consigned sweets to a small chamber labeled "use sparingly," but as low-fat cakes, cookies and snacks flooded the market in the early 1990s, consumers simply added them to what they were already eating, falsely assuming that anything low in fat must be harmless. "We were trying to promote lean meats and low-fat dairy products," says Marion Nestle, a New York University nutritionist who served as an adviser to the surgeon general in the late 1980s. "We never thought of Snackwell's."
It's not just the calories that make refined carbs so troublesome--it's the way they're digested. Unlike whole grains, which break down slowly in the digestive system, refined grains flood into the bloodstream as glucose. If that sugar isn't used immediately to fuel activity, the body produces a burst of insulin to ferry it out of circulation and into fat and muscle cells for storage. As most people now know, a diet rich in refined carbs and simple sugars can erode that system. Cells become increasingly resistant to insulin, forcing the body to produce it in ever-greater amounts. Eventually the system breaks down, triggering diabetes and fostering heart disease. An occasional glucose surge is no great hazard to a lean, active person. But as Willett observes, Americans were neither lean nor active when they started mainlining carbs. Small wonder that the rate of type 2 diabetes soared during the '90s.
Though experts bicker endlessly about how best to reverse these trends, no one denies that weight management is critical. So Willett places "daily exercise and weight control" at the base of the Healthy Eating Pyramid. There are, of course, countless ways to alter the balance between intake and output. But for most people, the most healthful strategy is simply to boycott junk. By giving up processed foods in favor of whole ones, almost any American can shed several hundred calories a day. Even the baked potato--one of Willett's bugaboos--is a better nutritional bargain than almost anything that comes in a package. Eaten with the skin on, it provides a full belly, a dozen vitamins and minerals, and as much fiber as a bowl of oatmeal--all for 150 calories. A bag of chips can easily pack 500, and the accompanying 20-ounce soda typically adds 250 more--all of it sugar.
A second point of consensus is that vegetables should be eaten in abundance. There isn't a diet guru on earth who denies their virtues. Heart doctors endorse them, cancer doctors endorse them, the USDA endorses them, even the low-carb king Dr. Robert Atkins endorses them. Unfortunately, no one can afford to promote spinach or bell peppers the way snack makers promote their goods. McDonald's spent $1.1 billion on advertising in 2001. That same year, the budget for the government's pro-vegetable "5 a Day for Better Health" program was $1.1 million. Not surprisingly, only 23 percent of U.S. adults were meeting the five-a-day target at last count.
When you venture beyond controlling weight and eating plenty of vegetables, the healthful diets start to look more different, but they still have similarities. Consider the rice-and-vegetable-based Asian diet and the traditional Mediterranean diet, which abounds in fish, nuts and olive oil. Both are models of good eating, strongly associated with vibrant health and long life. By the logic of the USDA pyramid, they can't both be good for you. But if you scrap the high-fat, low-fat distinction and use a good-bad scale, everything falls into place. Both diets rely on plants and fishes for fat. And though both include some refined grains, neither treats cinnabuns as a food group.
The obvious challenge is to devise an eating plan that embraces healthy cuisines, no matter how diverse, while discouraging the kind of excess that has taken hold in America. Willett's pyramid looks more Mediterranean than Asian. It calls for liberal amounts of unsaturated fat and warns us to use white rice as sparingly as Snackwell's. But the Healthy Eating Pyramid is no mere vote for fats over carbs. Good carbs (whole-grain foods) and good fats (plant oils) dominate the bottom floor of the building while the fast-burning carbs live with red meat in the attic. And instead of treating protein foods as a single group, Willett scatters them all over the house. Nuts and legumes rank first in the hierarchy, followed by fish, poultry and eggs. Dairy products--which shoulder half of the USDA pyramid's protein load--are optional in Willett's pyramid, easily replaced by a calcium supplement.
Willett's fellow nutritionists question many of his prescriptions. Some worry that he's making the same mistake with vegetable oil that the USDA made with carbs. "His idea of having the pyramid float on olive oil is delicious," says Nestle, "but that stuff contains 130 calories per tablespoon. Four tablespoons and you've had a quarter of your calories for the day." Others complain that he treats all plant oils as equals, even though most of us get plenty of corn oil (a source of omega-6 fatty acids) and too little flax and canola oil (which provide omega-3s). Still others fault him for treating rice and potatoes as the equivalent of sugary snacks. "You can't condemn white rice when more than a billion people live on it and maintain superior health," says Dr. John McDougall, author of several books on nutrition. "Sure, brown rice would be better, but 'use sparingly' is ridiculous."
The Healthy Eating Pyramid may still need refinement, but as a guide to good health it clearly trumps the USDA pyramid. In three recent studies, Willett and his colleague Marjorie McCullough have scored thousands of long-term participants in the nurses' and health professionals' studies on how closely their diets adhere to the USDA or Harvard guidelines. They've studied both men and women, and analyzed both heart disease and general ill health. The women adhering most closely to the USDA guidelines suffer just 14 percent less heart disease than those who flout them. But those scoring highest on Willett's scale suffer 28 percent less than those scoring the lowest. In every sample analyzed, the same pattern has held.
It will take more than a pyramid to improve America's diet. It will take motivation, awareness and a realization that eating well is more fun than eating badly. But it won't require a breakthrough in understanding. Science has shown us what works. Here's to making it happen.
Graphic: (illustration/photos/text) Redesigning the Food Pyramid: The food guide pyramid: The government's 1992 effort to wean us from fat conveyed a sense that all carbs are harmless.
CORRECTION: Our Jan. 20 graphic "Redesigning the Food Pyramid" indicated that the daily average American diet includes 4.9 servings from the meat, fish, poultry, eggs, nuts and dry beans group. In fact, it is about two servings. NEWSWEEK regrets the error.