New York City, Oct. 5, 2000 - The American Heart Association today unveiled its new dietary guidelines, which have been expanded to include specific recommendations tailored to an individual's risk of heart disease and stroke.
The guidelines, based on an analysis of hundreds of studies, will be published in the Oct. 31 issue of Circulation: Journal of the American Heart Association.
Ronald M. Krauss, M.D., the principal author of the guidelines and a senior scientist at the Lawrence Berkeley National Laboratory at the University of California, says the four main goals of the new guidelines are to help Americans achieve an overall healthy eating pattern; achieve and maintain an appropriate body weight; achieve and maintain a desirable cholesterol profile, and achieve and maintain a desirable blood pressure level.
Guidelines are food, not percentage based
For the first time, the guidelines stress the importance of preventing obesity and are easier to use because they stress overall eating patterns, rather than a percentage of dietary fat or other nutrients.
"We are emphasizing the positive message of what people should eat - for example, more plant-based foods," says Krauss. "In the past we have focused rather heavily on the percent of calories as fat and amounts of cholesterol. These are still important considerations, but the emphasis has shifted to allow consumers to understand the importance of an overall eating plan.
"Americans still need to limit saturated fats and cholesterol, but if they follow the new dietary guidelines, they will be consuming a balanced diet rich in nutrients, and may not need to calculate percentages or amounts of specific dietary components," he adds.
"When people eat out, it's hard to think about what percentage of the dinner comes from saturated fat. It's much easier to think about the various food groups."
Varied diet full of fruits, vegetables, grains and fish
A diet rich in fruits, vegetables, legumes (beans), whole grains, low-fat dairy products, fish, lean meats and poultry is still the basis of the recommendations. The association continues to recommend eating five servings of fruits and vegetables and six servings of grains daily. But, for the first time, two weekly servings of fatty fish, such as tuna or salmon, are recommended.
The association recommends that healthy adults minimize the intake of foods containing high levels of saturated fats (found in animal products and tropical oils) and substantially reduce the intake of trans fatty acids (the hydrogenated oil found in commercially prepared foods and some hard margarines). For individuals with risk factors for heart disease or existent heart disease, a further reduction in saturated fat intake is recommended. The Food and Drug Administration is considering the labeling of foods for trans fatty acids.
The recommended intakes of salt (less than 6 grams per day, or 2,400 mg of sodium) and dietary cholesterol (300 mg/day for healthy individuals, and 200 mg per day in high-risk individuals) remain unchanged. If an individual chooses to consume alcohol, the limit should be one drink a day for women and two drinks a day for men. People who do not normally drink alcohol should not begin drinking. The association still recommends that individuals get their nutrients from foods, not supplements.
Diet helps prevent weight gain, obesity
"Americans are eating too many calories, and are not getting much nutritional value from those calories," says Krauss. "Although the guidelines were developed to reduce or delay heart disease and stroke, Americans who follow them could reap many other benefits. Research indicates these nutritional steps could also decrease the risk of developing cancer or osteoporosis."
For obese individuals, the guidelines recommend a gradual weight loss of no more than one to two pounds per week. "Simply put, to lose weight, you must eat fewer calories than you burn and increase physical activity, such as brisk walking, to at least 30 minutes daily."
In addition, people consume many foods that are not "nutrient dense" which often have a lot of added sugars in them - for example sugary soft drinks and commercially baked goods.
"It is best if people reduce their caloric intake by following our guidelines for healthy adults - a diet rich in fruits, vegetables, low-fat dairy products, and leaner cuts of meat eaten in smaller portions," says Krauss.
Given the difficulty many people -- especially those between 25 and 45 years -- experience in trying to maintain a weight loss over time, the guidelines recommend efforts to prevent weight gain in the first place.
Targeting high risk populations
The guidelines offer a framework to assist health care providers in tailoring specific medical nutrition therapy to meet the needs of individuals with high blood pressure, cholesterol disorders, diabetes, insulin resistance, high triglycerides, congestive heart failure, kidney disease and/or obesity.
"For individuals with high blood pressure, losing just 5 percent to 10 percent of body weight is possible for many overweight individuals, and that modest amount of weight loss can significantly improve blood pressure," says Krauss. "In addition, consuming a diet rich in fruits, vegetables, low-fat dairy products and limiting salt and alcohol has been shown in a large study to have major benefits in controlling blood pressure levels."
In recent years, scientists have been studying individuals who have a cluster of metabolic risk factors for heart disease and/or stroke -- excessive fat tissue in the abdominal region, glucose intolerance or diabetes, high blood pressure, and high levels of triglycerides (more than 200 mg/dL). This cluster of risk factors is sometimes called "Syndrome X."
For individuals diagnosed with the syndrome, it may be desirable to avoid very low-fat, high carbohydrate diets, and to emphasize unsaturated fats, such as vegetable oils and seed oils (excluding tropical oils), rather than carbohydrates. Very low-fat diets (less than 15-20 percent of total calories from fat) with correspondingly high carbohydrate content can lower "good" cholesterol. The guidelines also weigh in on high protein and other popular diet strategies and note areas of study that need greater emphasis. For example, there is little scientific evidence to support the concepts that high protein diets result in significant changes in metabolism, sustained weight loss or improved health.
Others on the nutrition committee include: Robert H. Eckel, M.D. (Chair, Nutrition Committee); Barbara Howard, R.D., Ph.D. (Vice Chair, Nutrition Committee); Lawrence J. Appel M.D.; Stephen R. Daniels, M.D., Ph.D.; Richard. J. Deckelbaum, M.D.; John W. Erdman, Jr., Ph.D.; Nancy D. Ernst, Ph.D., R.D.; Penny Kris-Etherton, Ph.D., R.D.; Ira J. Goldberg, M.D.; Theodore A. Kotchen, M.D.; Alice H. Lichtenstein, D.Sc.; William E. Mitch, M.D.; Rebecca Mullis, Ph.D., R.D.; Killian Robinson, M.D.; Judith Wylie-Rosett, Ed.D, R.D.; Sachiko St. Jeor, Ph.D., R.D.; John Suttie, Ph.D.; Diane L.Tribble, Ph.D.; and Terry L. Bazzarre, Ph.D.