In one of our epidemiology programs

the Lipid Research Clinics Program we are attempting to determine the prevalence of hyperlipidemia, the actual distribution of cholesterol and lipoproteins, among major population groups, to assess the relationship between diet and lipid/lipoprotein levels and between these levels and coronary heart disease. Thus far, these studies have established population base line levels for plasma cholesterol, triglycerides, and lipoproteins. These base line levels are extremely important because without these data, it will be impossible to assess whether any change in the level of fats and other elements in the normal diet will lead to change in the blood levels of these substances. In recognition of the fact that the factors which determine the development of atherosclerosis may begin in childhood, these studies include a significant component dealing with children (from 1 to 19 years).

Another crucial aspect of the research into the relationships between diet, lipids and coronary heart disease is our clinical trials research. The Lipid Research Clinics' Coronary Primary Prevention Trial is a 10-year effort which involves nearly 4,000 men between 35 and 59. Studies focus on whether lowering cholesterol in essentially normal men who have elevated cholesterol levels will reduce or slow the development of coronary heart disease. The dietary objectives of the trial are to achieve moderate, long-term dietary intervention in patients taking cholesterol-lowering drugs and control groups, and to evaluate group changes in dietary intake after counseling. This trial is scheduled to be completed in 1983.

Another program which attempts to link not only diet to coronary disease but also smoking and hypertension, is the Multiple Risk Factor Intervention Trial. A group of 12,000 men aged 35-55 were identified as being at aboveaverage risk from death from coronary heart disease. We are attempting to see if we can affect a significant reduction in deaths due to coronary heart disease in half this group by lowering their serum cholesterol levels, reducing their blood pressure, and eliminating their smoking; the other half of the group were referred to their physician for usual care. The dietary intervention component of this trial is designed to modify the intake of lipids as well as sodium and potassium, using behavior modification techniques and a knowledge of group dynamics. We will evaluate the impact of these changes and our ability to help individuals achieve a long-term change in their diet. This trial is scheduled for completion in 1982.

We are also investigating the most effective means of disseminating health information. The Media Intensive Health Education Intervention Program is designed to measure the possibility of dietary intervention among the general public. The intervention is directed at two communities through mass media and small group discussions with people on how best to reduce the levels of cholesterol, triglycerides, saturated fats, calories, and salt in their diets. The same means of intervention are being used to reduce smoking. Three communities are serving as controls. The specific dietary goals include lowering levels of cholesterol, triglycerides, and low density lipoproteins, reducing high blood pressure

and obesity. Regular physical activity is also promoted. This type of activity represents the Institute's intention to learn how to affect diet modification while we still seek answers as to what should be affected.

Another many-faceted program ranging from fundamental and clinical research to community outreach programs is the National Research and Demonstration Center for Heart and Vascular Disease. Several of the diet-oriented community programs developed by the Center utilize community clinics and other forms of outreach, as well as Center facilities themselves.

The NHLBI also supports a program in collaboration with the U.S. Department of Agriculture and the Food and Drug Administration to compile comprehensive tables of nutritional data and food composition. These tables not only serve

the needs of the Institute but of the entire nutrition community.

The Institute has a variety of activities underway to disseminate cholesterolrelated information to the health care community and to the public, based on what we know and what we don't know. For example, to provide the physician with guidance in treating patients with specific blood-lipid disorders, we have distributed over seven million manuals and patient education pamphlets entitled, Dietary Management of Hyperlipoproteinemia. Together with the American Heart Association, we are staging a series of nutrition counseling workshops which will culminate in a "workshop package" to be used for training those engaged in nutrition counseling throughout the country. We have a series of nutrition awareness information projects directed at the

public. We completed a year-long pilot program with Giant Foods, Inc. to provide nutrition information to the shopper at the point-of-purchase. The Institute developed a "Food for Thought" game for use in cafeteria settings, which is now being distributed through the chapters of the American Heart Association. Materials related to nutrition and heart disease prepared by the Institute are being carried in monthly issues of airlines inflight magazines and on airport posters. The Institute has also produced more than 500-thousand copies of "Heart Attacks" a booklet for the layman which addresses risk factors, including cholesterol.

At this point, there is much to be done in making the physician and other health professionals better able to translate cholesterol into lipoproteins; in fostering research activities to establish a better understanding of diet and HDL and LDL; in providing the physician with more precise measurements of HDL; and improving our efforts to compile comprehensive tables of nutritional data and food composition.

These represent only a few of several efforts in which we are aggressively attempting to better understand and define the role of cholesterol and saturated fats in our diet and their relationship to coronary heart disease. We have good epidemiological evidence and animal data establishing cholesterol as a major risk for Coronary Artery Disease. But, we still need to answer such key questions as: "Does the lowering of cholesterol levels help prevent heart disease?" and "Towards what desirable cholesterol level should the general public strive?" When we have better information regarding these key issues, we may well be in a position to launch the type of comprehensive

national educational programs that have been conducted in the areas of smoking and high blood pressure.

In any case, as new information becomes available, we will quickly disseminate it to the health care community and to the public in our ongoing attempt to separate fact from "fancy".

Until we have additional information to further clarify this issue which is surrounded by confusion and controversy, the public would be wise to become familiar with the dietary guidelines for Americans which were issued earlier this year by the Department of Agriculture and the Department of Health and Human Services. These guidelines are consistent with

all the facts known at present and represent prudent advice which may indeed be quite beneficial to the health of the public.