Food Guide Pyramids - The Shape of Things to Come
When it comes to our daily fare, the only thing that doctors, dietitians, and government experts seem to agree on is the shape of the United States Department of Agriculture (USDA) Food Guide Pyramid. This familiar triangle, found on the packaging of most foods we consume, sends a simple message: eat generous amounts of the foods found at the bottom of the pyramid, and eat sparingly of those found at the tip. The controversy surrounding the food pyramid turns on which foods belong where and in what quantities.
Since the U.S. government adopted the food pyramid back in 1992, research on nutrition has evolved, making some believe that the current guidelines are obsolete. For example, while the recommendation that we consume large servings of bread, cereal, pasta, and rice, found at the bottom of the pyramid, sounds like good advice, there is no distinction made between "refined" foods, like white bread and white rice, and "unrefined" foods, like whole-grain breads and brown rice. Current research shows that it is not just their calories that make refined carbohydrates so troublesome---it is also the way our body digests these products. Whole grains break down slowly in the digestive system; refined grains are rapidly digested, flooding the bloodstream with the sugar glucose. If that sugar is not used immediately to fuel activity, the body produces a large burst of insulin to remove it from the bloodstream. Too much refined carbohydrate in our diets can cause cells to become resistant to insulin, forcing the body to produce it in greater amounts. Eventually the system can break down completely, triggering a host of problems like heart disease and diabetes, a disease that reached epidemic proportions in the 1990s.
While fat has long been considered offensive by most health-conscious Americans, new studies show that some fat may actually be good for us. Research has revealed that monounsaturated and polyunsaturated fats found in vegetable oils (such as canola and olive oil), nuts and other plant products, and fish are actually good for the heart. Two types of fat---saturated fat, found in whole milk and fatty red meat, and trans fatty acids, found in many margarines and vegetable shortenings---should be limited because they contribute to the artery-clogging process that leads to heart disease, stroke, and other problems. The current USDA guidelines, however, lump all fats together at the top of the pyramid, telling us to partake sparingly.
The problems with the USDA Food Pyramid have led some experts to devise other options. The Mediterranean Food Pyramid popularized in the mid-1990s, for instance, eschews processed products and emphasizes an abundance of food from plant sources, including fruits and vegetables, potatoes, breads and grains, beans, nuts, seeds, and seasonally fresh, locally grown foods. The Asian Food Pyramid emphasizes rice. The Latin Food Pyramid emphasizes fresh fruits, tubers, and grains.
One alternative getting significant attention is called the Healthy Eating Pyramid, devised by the Harvard School of Public Health. Their program emphasizes exercise, weight control, and hearty servings of vegetables, whole grains, and sunflower, corn, and soy oils. Nuts, which the current USDA guidelines recommend only in moderation, should be eaten one to three times a day, according to the Harvard experts. Red meat, butter, white rice, and bread should be eaten sparingly.
The Harvard recommendations are based on rigorous research that assessed the diets of more than 100,000 men and women for 10 to 15 years. The researchers found that the reduction in the risk of chronic disease was nearly twice as great for those whose diet met the new guidelines as for those whose eating patterns reflected the recommendations laid out in the USDA food pyramid. Of course the USDA's current guidelines are not completely off base. Their message of eating smart by keeping fat intake low and loading up on vegetables, fruits, and grains has helped keep us healthier. Research has shown that women whose diets most closely correspond to the USDA recommendations have a 30% lower mortality rate than women whose diets least adhere to the guidelines.
Despite the plethora of nutritional information available, however, it is clear that many Americans are not paying much attention to either the USDA recommendations or any of the alternatives. Despite the popularity of low-fat foods and high-profile diets, the percentage of overweight Americans increased over the past decade, according to the 1999-2000 National Health and Nutrition Examination Survey. By 2000, more than 60% of adult Americans were considered overweight or obese. The percentage of overweight teens had risen from 15% to 21%, as had the percentage of overweight adults (from 26% to 34%). In fact five out of the ten leading causes of death for Americans, including heart disease, some cancers, stroke, diabetes, and atherosclerosis, relate to dietary practices.
If food were merely a source of sustenance and pleasure, deciding what to eat would be simple; trying to make food choices that will keep us healthy, however, gets complicated. The USDA is set to release a new pyramid in 2004, which may reflect some of the newest nutritional information. The new version of the familiar nutrition symbol may require us to change our way of thinking about our daily bread---and about the shape of our diet, and the resultant contour of our bodies, as well.
Since the U.S. government adopted the food pyramid back in 1992, research on nutrition has evolved, making some believe that the current guidelines are obsolete. For example, while the recommendation that we consume large servings of bread, cereal, pasta, and rice, found at the bottom of the pyramid, sounds like good advice, there is no distinction made between "refined" foods, like white bread and white rice, and "unrefined" foods, like whole-grain breads and brown rice. Current research shows that it is not just their calories that make refined carbohydrates so troublesome---it is also the way our body digests these products. Whole grains break down slowly in the digestive system; refined grains are rapidly digested, flooding the bloodstream with the sugar glucose. If that sugar is not used immediately to fuel activity, the body produces a large burst of insulin to remove it from the bloodstream. Too much refined carbohydrate in our diets can cause cells to become resistant to insulin, forcing the body to produce it in greater amounts. Eventually the system can break down completely, triggering a host of problems like heart disease and diabetes, a disease that reached epidemic proportions in the 1990s.
While fat has long been considered offensive by most health-conscious Americans, new studies show that some fat may actually be good for us. Research has revealed that monounsaturated and polyunsaturated fats found in vegetable oils (such as canola and olive oil), nuts and other plant products, and fish are actually good for the heart. Two types of fat---saturated fat, found in whole milk and fatty red meat, and trans fatty acids, found in many margarines and vegetable shortenings---should be limited because they contribute to the artery-clogging process that leads to heart disease, stroke, and other problems. The current USDA guidelines, however, lump all fats together at the top of the pyramid, telling us to partake sparingly.
The problems with the USDA Food Pyramid have led some experts to devise other options. The Mediterranean Food Pyramid popularized in the mid-1990s, for instance, eschews processed products and emphasizes an abundance of food from plant sources, including fruits and vegetables, potatoes, breads and grains, beans, nuts, seeds, and seasonally fresh, locally grown foods. The Asian Food Pyramid emphasizes rice. The Latin Food Pyramid emphasizes fresh fruits, tubers, and grains.
One alternative getting significant attention is called the Healthy Eating Pyramid, devised by the Harvard School of Public Health. Their program emphasizes exercise, weight control, and hearty servings of vegetables, whole grains, and sunflower, corn, and soy oils. Nuts, which the current USDA guidelines recommend only in moderation, should be eaten one to three times a day, according to the Harvard experts. Red meat, butter, white rice, and bread should be eaten sparingly.
The Harvard recommendations are based on rigorous research that assessed the diets of more than 100,000 men and women for 10 to 15 years. The researchers found that the reduction in the risk of chronic disease was nearly twice as great for those whose diet met the new guidelines as for those whose eating patterns reflected the recommendations laid out in the USDA food pyramid. Of course the USDA's current guidelines are not completely off base. Their message of eating smart by keeping fat intake low and loading up on vegetables, fruits, and grains has helped keep us healthier. Research has shown that women whose diets most closely correspond to the USDA recommendations have a 30% lower mortality rate than women whose diets least adhere to the guidelines.
Despite the plethora of nutritional information available, however, it is clear that many Americans are not paying much attention to either the USDA recommendations or any of the alternatives. Despite the popularity of low-fat foods and high-profile diets, the percentage of overweight Americans increased over the past decade, according to the 1999-2000 National Health and Nutrition Examination Survey. By 2000, more than 60% of adult Americans were considered overweight or obese. The percentage of overweight teens had risen from 15% to 21%, as had the percentage of overweight adults (from 26% to 34%). In fact five out of the ten leading causes of death for Americans, including heart disease, some cancers, stroke, diabetes, and atherosclerosis, relate to dietary practices.
If food were merely a source of sustenance and pleasure, deciding what to eat would be simple; trying to make food choices that will keep us healthy, however, gets complicated. The USDA is set to release a new pyramid in 2004, which may reflect some of the newest nutritional information. The new version of the familiar nutrition symbol may require us to change our way of thinking about our daily bread---and about the shape of our diet, and the resultant contour of our bodies, as well.
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