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Dr Dwyer: I would like to turn to the fourth goal of the conference as set out by Dr Milner: to look at challenges to developing and making available to consumers appropriately researched and evaluated products in the light of current regulatory barriers. I am not sure the regulatory barriers are the only barriers. I think the other barrier is evidence—exactly what the state of the evidence is, given the current emphasis on evidence-based medicine.
I want to review the visions for health that have dominated over the last century or so and present you with 4 paradigms for your consideration. We all know that many diseases probably have some risk factors associated with diet. Earlier in this century, health planners started thinking about health care resources and began to build hospitals to provide health services and medical care to large numbers of people. This "war on disease" paradigm, in which disease was fought by improving health resources, dominated until after World War II.
Next, health care planners became concerned with geographic and financial access to health care, and the second paradigm, "access to care," became popular. The introduction of Medicare in 1965 improved access to care for older people by paying a large proportion of their hospital bills. However, the access problem remains for the >40 million people in the United States who still have no, or only very limited, health insurance.
In the last few decades, health planners have been preoccupied by the problem of rising health care costs and have adopted the managed care model, leading to dominance by the "managed care" paradigm. The theory behind this model is that costs would be reduced (and thus the price of medical care would drop) while good health care was still provided. But within the last decade, health planners have turned to the fourth paradigm, the "market-driven managed care model," which emphasizes decreased prices and costs, managed care delivery, and improved health plan options, and which adds competition between plans on cost. All of this has led to consolidation within the industry and in some respects to better organization, but there have also been negative consequences, including the risk of not providing enough service.
At present there are integrated medical care delivery systems to better manage costs, but improved health and continuity of care have still not been achieved, and in other respects advances have been slow. More than 40 million Americans are still outside the system, with no or only minimal health insurance.
Today, people are beginning to think about things other than medical care resources that have to do with health. Resources such as education and food also produce health, and these larger systems must also be considered.
Some of the terms that I heard in the last 2 d deserve mention: ecology and botany; discussions about models, model systems, and mathematical models; and how these are correlated with each other and with biomarkers of underlying histologic processes. Legal evidence, scientific evidence, and evidence-based reviews of the literature have often been mentioned as well. We must keep all of those concepts in mind. We have also talked a lot about food composition databases: how very much larger they have to be and what they need to include.
Dr Marriott's presentation underscored the need to think about nutrition in a much broader context than we ever have before. In terms of inputs that produce health, we now recognize factors far broader than medical services alone or even traditionally defined health services. Inputs such as physical and social environments, food, and income are health inputs as well. We need to think ecologically as we enter the 21st century. We need to develop one health-focused science out of many, one way of looking at things out of many. The discussion we have heard today reflects that more integrated view. We need to continue a dialogue with toxicologists, food scientists, pharmacologists, pharmacists, classic nutritionists, ecologists, and many other disciplines. Finally, we need to work to ensure that the claims of product benefit really exist.
Dr Fernstrom: Many companies are making products such as dietary supplements that have no particular benefit. For me, the important issue is that we seem to have a system that is taking away our ability to ensure that no harm is done. Personally, I care less that the product is ineffective than that it may be harmful.
The "do no harm" principle has not been adequately addressed. As you point out, Dr Harper, it may be simply because the political process has provided a way around appropriate regulations, but that does not change the reality of the problem.
Dr Harper: Part of the problem arises from the political process; another important part of the problem is the danger of consumer demand driving nutritional science and posing a threat to its integrity. Superstition and magic are often the basis for the desire for foods, natural products, medicines, and anything else that promises to lengthen life and prevent disease. Sometimes I think we have gone too far in promising to prevent disease and increase longevity. We need to consider that the greatest advances we have made in increasing life expectancy have been through sanitation and feeding infants. Also, I don’t think we give enough credit to medical advances, especially vaccines and drug advances.
Life expectancy has increased substantially in this century, but I don’t know of any evidence that longevity has increased greatly. It is the proportion of people surviving through early life that has contributed so greatly to the high proportion of elderly. The survival curve has tended to become more sharply angled than it was before. More than 80% of newborn infants in wealthy nations live to be 65 y of age these days [World Health Organization. World health statistics annual. Geneva: WHO, 1995].
We need to be careful about what we claim we can achieve through nutrition. We must be careful not to claim we can achieve the impossible.
Dr Hecker: It is true that the longevity curve beyond 65 y has not changed a whole lot. What is changing radically is the demand for quality of life. People want to live their lives full throttle, with all systems "go" until the day before they die. That's the kind of quality of life that this population is demanding from us.
Nutrition, as it has evolved over the last 20 y, has probably replaced the study of infectious diseases as the number one public health science. People are demanding answers with regard to the problem of longevity from the nutrition community. If you consider the top 5 or 6 killers in the country, virtually all of them are impacted by nutrition. The expectation is that since nutritional intake affects the course of these diseases, to benefit from optimal quality of life one should modify their intake in ways that positively affect health. People want sound information with regard to ways to achieve this goal, including what tools to use.
Dr Dwyer: To follow up on that point, I’m concerned about a trend toward making prescription drugs available over the counter or advertising them directly to the consumer without, at the same time, educating consumers about their appropriate use and the risk that may be involved in their inappropriate use. Also, some advertising claims for the benefits of some of these products are dubious.
Dr Bistrian: In this regard, the drug companies are bypassing the medical community and going directly to the consumer.
Dr Marriott: With regard to Dr Hecker's comment, in addition to reducing the risk of chronic disease or preventing disease, people want advice on nutritional means of enhancing performance.
Dr Bistrian: Do we really believe that if we were to optimize nutrition, we would accomplish those goals?
Dr Harper: I’m not sure I believe that.
Dr Bistrian: In yesterday's Wall Street Journal (February 21, 1998), it was reported that New Orleans has the highest mortality rate of any American city because of lifestyle, much of which is related to nutrition. It's hard to ignore that kind of evidence.
Dr Harper: What you can achieve by diet is to reverse the results from an inadequate diet or inappropriate lifestyle; but going beyond a certain level just by modifying lifestyle is, I think, wishful thinking.
For centuries, we have believed there was some kind of magic potion that would give us longevity and prevent disease. When you consider genetic factors and chance (eg, disease, accidents), there is a limit to what you can achieve by nutrition, and we need to recognize this.
Dr Weisburger: With some elements we have markers, such as cholesterol. For other indicators of health, we don’t yet have markers. I think future nutrition successes will in part involve the development of better markers of health. I think it is possible to delay the effects of aging by adopting a lifestyle that includes exercise, antioxidants, vegetables, fruits, tea, and no cigarette smoking. I think that as we enter the next millennium, we can make sound public health recommendations for macronutrients, micronutrients, and supplements.
Health is the goal, the touchstone of what we are after, not disease cure or therapy. We want to prevent diseases by adopting a healthy lifestyle.
Dr Hathcock: In regard to Dr Harper's comments, none of us would expect all research projects to find something that is going to be helpful or beneficial or perhaps even safe. Likewise, not all products on the market are going to be helpful and beneficial, and perhaps not all of them will prove safe in the long term. On the other hand, there are many success stories: vitamin E and the heart, calcium and osteoporosis, and folic acid and neural tube defects, to name a few. Moreover, I have no doubt that homocysteine reduction will soon be recognized as an additional benefit from folic acid consumed for the prevention of neural tube defects. Given these successes, we need to remain optimistic but cautious about the potential benefits of nutrition intervention.