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balance, and that we can provide the American people with healthy diets.
What is very important, as I view it, is that they have an adequate supply of healthy food at a price that the consumer can afford to pay. I am just pointing that out.
Dr. HEGSTED. We certainly agree with that and we think that is achievable with a more moderate diet than Americans are now eating. We are not recommending that Americans consume less meat. We are trying to recommend that they consume leaner products. We think there are opportunities for the food industry to provide a more nutritious diet than Americans now have.
Mr. WAMPLER. I have one final question. That is in your image, as you view it. There are others who disagree with you and say you are wrong.
Dr. HEGSTED. I realize that we are never going to have a unanimous opinion on anything, I guess. I do not see how one can do other than
I to rely on duly constituted competent scientific groups that cover the range of expertise and experience in this area.
We believe that we can quote 20 or 30, or more, national and international expert groups that are essentially in consensus. That does not deny that there will always be some people who are not in consensus, but how else do we evaluate scientific data !
Mr. RICHMOND. Thank you, Mr. Wampler. Mr. Waxman?
Dr. Hegsted, the Academy report draws a distinction between healthy individuals and those at risk of heart disease. How helpful is that distinction? What percentage of the American population falls into the Academy's definition of healthy?
The Academy concludes that healthy persons need not be concerned about the amount of cholesterol in their diets. How do we know whether we are healthy enough not to worry about reducing our cholesterol intake?
Dr. HEGSTED. I think we do not know. I think that is the issue. Our ability to characterize those at risk is not very good.
People might do better than we do. I think if a person is lucky enough to have a serum cholesterol level of 175, he can afford to be fairly relaxed in terms of fat and cholesterol intake, but there are very few people of that kind.
They say you should go and have your blood lipids, blood pressure, and family history evaluated and if they are abnormal then get some advice, but they do not define what they mean by abnormal.
As I pointed out, we think most Americans are at risk of one of the chronic diseases and about half of us are at risk of heart attack. With a problem of that magnitude, we believe general dietary advice is what Americans need.
Mr. WAXMAN. Is it fair to say, due to the nature of coronary heart disease, that prevention is the primary means by which a reduction in morbidity and mortality can be realized ?
Dr. HEGSTED. We would certainly agree with that. The treatment is not very effective and it certainly is expensive.
Mr. WAXMAN. Therefore, if we are trying to prevent this disease, it seems to me that diet is one of the most fundamental
preventing or reducing morbidity and mortality levels among our population. Therefore, the Academy's conclusion that we ought to decide whether or not we are healthy and then decide about ingesting high levels of cholesterol based on that knowledge, really does not help us in terms of a public health approach to trying to deal with heart disease.
Dr. HEGSTED. That is right. We believe public health problems have to be approached with public health methods. We simply cannot rely on treatment for these kinds of diseases.
Mr. WAXMAN. The public is, of course, bombarded by differing opinions by scientists on a number of issues. Should we look at this debate over cholesterol as just an honest disagreement between competent scientists such that the consumer ought to choose whatever side suits his desired lifestyle?
Dr. HEGSTED. I think it is unfortunate, but everything gets debated in public these days and I do not know what one can do about it.
I think, from everything we know, there is essentially a consensus of scientific opinion that would support our dietary guidelines. That does not mean it is unanimous. We believe that is the opinion of the major experts in the field.
Mr. WAXMAN. Let me pose the issue in a different way. If the National Academy of Sciences' report is correct, healthy Americans may indulge themselves in whatever amounts of cholesterol they choose. Millions of Americans will avoid inconvenient or unpleasant changes in their diets. They will be able to have eggs every day and butter on their toast.
If, on the other hand, the mainstream of American health experts are correct, by following their recommendations, we will reduce the number of heart attacks and other cardiovascular diseases and lives will be saved and lengthened. It seems to me, when we talk about a risk/benefit analysis, that is the kind of risk and benefit we are being asked to weigh.
It is rather cavalier to ignore the epidemiologic evidence about the danger of cholesterol in exchange for a petty personal food preference. Is that not what we are talking about?
Dr. HEGSTED. I think we would agree with you, Congressman.
Mr. WAXMAN. Thank you very much for your testimony and your answers to these questions. I think that, as I said earlier, the National Academy of Sciences' report is disappointing because it is based on a distinction that cannot be justified. That is, that healthy people, whatever that may mean and whomever that may include, can ignore the potential risk that all of us as a society face from high levels of cholesterol and the potential of heart disease that can result from it.
Mr. RICHMOND. Thank you, Mr. Waxman.
Dr Hegsted, it has been a pleasure, as always, to have you here. I think your testimony and answers to our questions certainly helped to clear up this matter. Thank you very much. Dr. HEGSTED. Thank you very much, Congressman.
Mr. RICHMOND. Our next witnesses are a panel of two eminent physicians, Dr. Antonio M. Gotto, Jr., professor and chairman of the
department of medicine at the Methodist Hospital of Houston, Tex., and Dr. Ernest L. Wynder, president of the American Health Foundation of New York, N.Y. I believe Dr. Wynder is accompanied by Dr. Charles Arnold, vice president for research and health maintenance of the American Health Foundation.
Dr. Gotto, it is a particular personal pleasure to me to have you here. As I said, you are not only the chairman of the department of medicine but you are an internationally esteemed and acclaimed expert in the whole field of cardiovascular diseases. You are a great cardiologist and a great friend of mine. I consider it a privilege to have you here to listen to you. STATEMENT OF DR. ANTONIO M. GOTTO, JR., PROFESSOR AND CHAIR
MAN, DEPARTMENT OF MEDICINE, THE METHODIST HOSPITAL, HOUSTON, TEX.
Dr. Gotto. Thank you very much, Mr. Chairman. It is a pleasure for me to be here.
I would like to add that my statement carries the endorsement of the American Heart Association.
I would very briefly like to summarize the points and issues on which there is a consensus or an agreement and then turn to those on which there is disagreement.
First, there is more atherosclerosis and coronary artery disease in developed societies than in lesser developed societies.
Second, the lesser developed societies have a lower consumption of animal or saturated fat and have significantly lower levels of cholesterol.
Third, atherosclerosis and blood cholesterol levels are higher in Western and developed societies.
Fourth, while it is possible to show changes with diet and blood lipid levels in coronary diseases between societies, within a society it becomes more difficult to do so. However, if one examines groups within a society with significantly different dietary habits from the general population, such as vegetarians and Seventh Day Adventists, one finds that they have significantly lower levels of cholesterol than the average of the general population. Seventh Day Adventists also have a significantly lower rate of coronary artery disease than does the general population in our country.
Fifth, based on all major epidemiologic studies done to date, an elevation of blood cholesterol is strongly associated with increased risk of coronary artery disease.
Sixth, the causes of coronary artery disease are multifactorial. Hyelevation of blood cholesterol is strongly associated with increased risk factors, along with hypercholesterolemia.
Seventh, there is considerable genetic variability in the susceptibility to developing coronary artery disease.
Eighth, dietary changes can reduce the blood cholesterol levels of most individuals.
I think the National Research Council panel would agree with those statements.
The final scientific proof that cholesterol lowering will prevent coronary heart disease, or reverse it, is lacking, as has been said. A num
ber of dietary studies have shown that it is possible to lower cholesterol by 12 to 18 percent.
Drug studies have also been carried out concerning cholesterol lowering. I think that the statements read from the panel, on page 10, are incorrect. That is it has not been proven that lowering these levels by dietary intervention will consistently affect the rate of new coronary events. I think the studies show that it is possible to reduce the incidence of nonfatal myocardial infarctions, but there is no evidence at this point that mortality can be reduced.
As to what studies are likely to give an answer to whether or not cholesterol lowering will reduce cardiovascular mortality, one of these is the lipid research clinic trials which are currently being supported by the National Heart, Lung, and Blood Institute.
With regard to diet, what can be expected! An average group of individuals will reduce their cholesterol by approximately 10 percent on the prudent heart diet recommended by the American Heart Association, which is very similar to that that Dr. Hegsted described, which is consistent with the guidelines of the U.S. Department of Agriculture.
The extremely zealous individuals will have a greater reduction, but the response from excellent adherers will, over a period of time, be one of about 15 to 20 percent reduction of cholesterol.
Now, let us turn to the area of research of the American Academy of Sciences Food and Nutrition Board. Based on what we know should recommendations be made to the general public concerning their diet? The Board has said no, at least with regard to consumption of dietary fat and cholesterol. In their report, the panel makes a plea for moderation with regard to diet and recommends control of obesity. I strongly concur in these views.
The major criticism I have of the report, “Toward Healthful Diets," is toward its lack of consistency. For example, in discussing the prevention of cardiovascular disease, the panel takes the position that since we do not have the final evidence that lowering cholesterol through diet or through other means will prevent coronary artery disease, then we should not make recommendations for the general public.
In one section of the report it is stated that the healthy person, who has no symptoms, should not be concerned about the fat consumption in his diet. However, after an individual develons symptoms, such as angina pectoris or has had a myocardial infarction, then he is much more likely to benefit from a diet than an individual who has not yet developed atherosclerosis.
The inconsistency of the panel is shown in dealing with other dietary factors in comparison with their position on dietary fat. For example, with regard to hypertension and salt intake. The panel recommends achieving a salt intake of 3 grams per day. The epidemiologic evidence on which this conclusion is based is, in my opinion, much weaker than that for dietary fat and cardiovascular disease.
The panel states that there is very little evidence that reducing salt intake to this level would produce any harm and uses the reasoning that "furthermore, 15 percent of the population is susceptible to develop hypertension.'
Coming from a part of the country, Houston, Tex., where the weather is very hot and humid and where there are many people
working on oil rigs and in oil fields, and where there are thousands of joggers, such a sweeping dietary recommendation for the general population in Houston in July and August might indeed be hazardous, yet the Board is willing to recommend that all healthy people reduce their salt intake to this level on the basis that 15 percent of the total population are at risk for hypertension.
In the case of cholesterol and coronary disease, approximately 50 percent of the population is at risk of coronary disease, as we have heard Dr. Hegsted comment, yet the Board is unwilling to take a position concerning dietary fat in reducing average cholesterol concentration in the general population.
In order to achieve a 3-gram salt intake, it would require not only leaving saltshakers off the table, but would also necessitate preparing all foods without adding any salt in the preparation. Putting the American population on a salt-free diet, I maintain, is a very drastic change for which there is very little epidemiologic evidence.
I recommend to my patients that they leave the salt shakers off the table and that they not add salt to their food after the cooking, but the recommendations this panel is making to the general population is a very sweeping one that I would not endorse, and one which goes beyond the position of the American Heart Association.
My point is that it is an inconsistent position based on the one which the panel takes with respect to dietary fat, about which they are quite skeptical and therefore say, “do nothing."
Similarly, with regard to alcohol, the panel recommends that Americans limit their alcohol intake to no more than three drinks per day. I strongly recommend moderation in consumption of alcohol to my patients, but where is the control trial with alcohol which the panel asks for in the case of cholesterol? Again, there is an inconsistency in the approach used by the panel.
A similar argument can be made about moderate obesity. Where are the clinical data on which this recommendation is made by the panel?
I believe that any dietary recommendation made to the general public carries with it some degree of risk. Such risk may be small but changes in dietary habits and in food consumptions may lead to alterations in the purchasing of food and to unknown risk to individuals who are in a precarious state of nutritional balance, such as economically deprived and elderly people.
Most of the world's population eat a low-fat, low-cholesterol diet, particularly that part of the world which has a low incidence of coronary heart disease and atherosclerosis.
The task force of the American Society of Clinical Nutrition, chaired by Dr. Ahrens, whom the panel quotes, and Dr. William Conner, concluded that there is no evidence that a low-fat diet, per se, is harmful. The same panel concluded that there is no evidence that low-cholesterol diets are harmful or that dietary cholesterol is an essential nutrition in human nutrition.
In conclusion, medical practice must often be based on the best available existing evidence, even though it falls short on final scientific proof. Certainly, all of the scientific evidence concerning the diet in coronary disease and the interrelationships is not in, but even when much more evidence accumulates from clinical trials there will con