Nutrition and Science

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Although awareness of the relationship between food and health has a long history, the science of nutrition developed out of discoveries in modern chemistry and medicine. The professionalization of nutrition science resulted in its directly influencing food production, preparation, and consumption. Increased influence also meant increased responsibility to the public and the food industry as well as to governmental and international agencies. Such issues as the safety of food and its just distribution led to both controversies and codes of ethics. Nutrition scientists have not always recognized and analyzed the relationship between their work and moral values, but with the growth of the world's population and the increase in knowledge of what constitutes a healthful diet, the ethical debates surrounding nutrition science are likely to multiply and deepen.

Historical Developments

As with their animal ancestors, members of Homo sapiens, in order to survive, learned about edible fruits, vegetables, and animals from experience, and to increase the quality of their lives in difficult conditions, humans domesticated crops and animals for food. Though the process was slow, they also learned how to improve plants and animals by selection and hybridization. Before the science of nutrition developed, humans had discovered how to exploit such microorganisms as yeast and bacteria to manufacture such new foods and beverages as cheese and beer. By the use of salt and desiccation, they could also preserve foods to sustain life during times of shortages.

In the nineteenth century, as chemistry became a sophisticated discipline, knowledge of complex organic compounds allowed researchers to pinpoint foodstuffs essential for good health and to reveal insalubrious or fraudulent foods. Technological changes associated with food production during this period were much more dramatic than in the previous millions of years of Homo sapiens' evolution. During the nineteenth century problems associated with rapid industrialization, such as polluted water, adulterated food, and inadequate sanitation in overcrowded slums, led to the public health movement in England, Germany, France, and the United States. Stimulated by ethical concerns, public health officials alerted citizens to the dangers of foods that were nutritionally inadequate, sometimes even dangerous. For example, milk, traditionally viewed as a nutritious food for most children, could be the carrier of disease, until Louis Pasteur introduced a procedure, pasteurization, whereby heating milk killed infectious microorganisms. Advocates of pasteurization, however, were often opposed by members of the food industry who wished to avoid additional costs. In the 1880s in the United States, the agricultural chemist Stephen M. Babcock attacked milk adulteration by discovering an efficient test to determine milk's fat content, which did more, according to a Wisconsin governor, to promote ethical behavior among dairymen than reading the Bible.

The most dramatic developments in the science and technology of nutrition occurred in the twentieth century when new knowledge, techniques, laws, governmental agencies, and public policies contributed to extending life expectancies in many industrialized nations in Europe and America by over twenty-five years. But at the beginning of the century nutrition science remained in its infancy as, for example, many physiologists believed that what kind of food people ate mattered little, as long as diets supplied enough energy (calories) and sufficient materials (proteins) for the body's growth and maintenance. Only slowly did scientists discover the importance of trace nutrients for ideal health.

During the first third of the twentieth century researchers found that such diseases as rickets, beriberi, and scurvy had a specific dietary origin. Lack of small amounts of vitamins (water-soluble or fat-soluble organic substances essential for good health) caused these diseases. Concurrently American and German scientists, studying the roles of amino acids in nutrition, found several of these compounds essential to good health. Furthermore, work done largely in the United States indicated that, besides vitamins and amino acids, the healthy survival of experimental animals and humans required in their diets such inorganic elements as sodium, potassium, calcium, magnesium, iron, zinc, and phosphorus. This accumulated knowledge was so important that, by the time of World War II, the National Research Council published a set of Recommended Dietary Allowances (RDAs) for foods, vitamins, and minerals. Though concerns growing out of wartime food rationing prompted this list, RDAs proved so helpful that they continued to be periodically issued, with modifications based on up-to-date nutritional research.

Nutritional Professionals and Ethics

The communication and multiplication of discoveries by nutrition scientists was facilitated by the formation of professional organizations and journals. For example, the American Institute of Nutrition began publishing its Journal of Nutrition in 1928, and in 1939 several important nutrition scientists in the United Kingdom formed the Nutrition Society, whose official publication was the British Journal of Nutrition. In the decades after World War II, agricultural chemists discovered high-yield crops that enabled farmers to produce enough food to nourish every person on Earth (the "green revolution"). Nevertheless, hundreds of millions of people remained malnourished, presenting concerned authorities with profound ethical problems, because the United Nations (UN) as well as various religious organizations maintained that every human had an inalienable right to be free from hunger and deficiency diseases.

At the UN, the Standing Committee on Nutrition established an Intergovernmental Working Group to develop guidelines for the implementation of the right to adequate food, as recommended by the 2002 World Food Summit. As international and national agencies and various professional societies became sensitive to the ethical implications of food and nutrition, so did trade associations involved with the production of foods and dietary supplements. For example, the Council for Responsible Nutrition, a trade organization, developed a code of ethics "dedicated to enhancing the health of the American public through improved nutrition, including the appropriate use of dietary supplements." This organization, founded in 1973, played an important role in several laws passed by the U.S. Congress in the last quarter of the twentieth century regulating nutritional substances.

Despite these ethical codes, laws, and world conferences, the numbers of the malnourished, according to reports issued by the UN's Food and Agriculture Organization, continued to increase in the decades after World War II. Some believed that the problem could be solved only in terms of development, that is, providing poor countries with the scientific and technical know-how to grow the food they needed. Others criticized this approach, because technology, while it could help to increase crop yields and improve food distribution, could prevent neither natural disasters nor political turmoil. Still others believed that malnutrition, which occurred not only in developing but also in developed countries, is a complex problem involving science and technology as well as economics, politics, and culture. These people held that what was needed was a multifaceted program that, while introducing new foods and technologies, also paid attention to economic growth, health education, and regional ecologies and cultures.

Safety and Equity

Unlike early nutrition scientists, who were able to link various diseases to specific dietary causes, modern researchers have discovered that such diseases as cancer and arteriosclerosis have multiple causes. According to some researchers, foods high in saturated fats will increase blood cholesterol levels, and many nutrition scientists agree that elevated levels of low-density lipoproteins (LDLs), which carry most of the cholesterol, increase the risk of coronary artery disease. Based on this evidence some criticized McDonald's and other fast-food restaurants for selling unsafe foods. Indeed, some critics went so far as to attack the majority of American food-production companies for reducing the consumption of fresh fruits and vegetables and increasing high-fat, high-sugar artificial foods, thus being partially to blame for such health problems as obesity, diabetes, and heart disease.

Cultural groups and their associated ideologies often influence dietary practices. Some traditional foods, such as green tea in Asian countries, have proven to be beneficial, but other practices, such as Latin American mothers' withholding milk and eggs from sick children, are harmful. Several cultural groups have practiced vegetarianism for a variety of social, religious, economic, or nutritional reasons. Some prominent nutritionists have attacked vegetarianism, insisting that meat is needed to avoid deficiencies of such essential substances as vitamin B12. Others have pointed out, however, that there are hundreds of millions of Hindus, most of whom do not consume any animal products throughout their lives, and few of them exhibit B12 deficiencies and they generally have reduced incidences of heart disease, colon cancer, and diabetes.

A principal aim of the ethics of nutrition is to improve the food habits of people, and an important component of this good work is to understand a country's culture. Equity requires that every human being in every culture has the right to be properly nourished. Consequently developed countries, with their surpluses of food, have a duty to the undernourished in developing countries. Even in developed countries citizens have the right to be provided with good food, but in the United States, for example, many consumers have either wasted their money or harmed their health by various food and diet fads. Many nutrition scientists consider it unethical for "medical quacks" to be making large amounts of money in this way from gullible Americans.

Nutrition Controversies

While many believe that science and technology should be an important part of the solution of such problems as malnutrition, others see science and technology as part of the problem. For example, scientists invented various herbicides to aid farmers in food production, but some of these herbicides were used in the Vietnam War to deprive people of food. This was certainly not the first war in which participants used starvation as a weapon, as the siege of Paris during the Franco-Prussian War (1870–1871) and the siege of Leningrad by the Germans during World War II make clear.

Controversies also exist about what constitutes a balanced diet and whether or not dietary supplements should be used. For example, medical researchers and nutrition scientists seem to have reached agreement that Americans should reduce fats in their diets, an assertion repeatedly confirmed by the U.S. Department of Agriculture's dietary guidelines and in its widely disseminated Food Guide Pyramid, in which fats and sweets occupy a tiny area at the pyramid's top, indicating that fats, oils, and sweets should be consumed only "sparingly." But recent critics of the "dogma of the deadliness of dietary fats" have pointed out that the data are ambiguous on the benefits of low-fat diets. Despite the proliferation of reduced-fat food products, obesity and diabetes have actually increased. Furthermore, epidemiological studies of countries such as France, where animal fat consumption has risen, have shown that heart-disease death rates have declined.

Mainly in Western countries, recent controversies have centered on anorexia nervosa, a self-imposed starvation disorder, and bulimia, a binge–purge eating disorder. Scientists are divided over the roles played by society and the media as well as by a person's genetic makeup, psychological state, and physiology in fostering such conditions. Other controversies over vitamins, herbs, and fiber in the diet have revealed the complex interrelationships existing among professional nutritionists, members of the natural-foods movement, food producers, and various scientists outside the nutritional field. Ethical issues are inextricably bound into these controversies because of various conflicts of interest. For example, the work of some nutrition scientists has been supported by food producers, but advocates of megavitamin therapy for health problems ranging from the common cold to cancer have accepted contributions from companies manufacturing these vitamins. Some who express concern over the unregulated sale of herbs and nutritional supplements want the government to control their use the way they do prescription drugs, but those who consider these substances as foods see such actions as infringing their freedom of choice.

Advances in medical technologies have also raised concerns about the nutrition of the elderly and dying. Many religious ethicists distinguish between ordinary and extraordinary means of treatment, claiming that a moral obligation exists to use ordinary means (food and water) to maintain life but no strict obligation exists to use extraordinary means (respirators). Others hold that no obligation exists to continue feeding a patient when only biological, not mental, life remains; still others argue that this assessment exhibits an impoverished view of human personhood. Ethical issues raised by feeding the world's poor, sick, and dying are certainly controversial and complex. Scientific knowledge and new technologies can help solve some of these problems, but they may exacerbate others. Further complexities will confront humankind in the future, because nutrition is an evolving science. As research generates new knowledge and technologies, ethicists, as they have in the past, will have to take into account this expanded understanding in making their moral judgments.


SEE ALSO Agricultural Ethics;Food Science and Technology.


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Sanjur, Diva. (1982). Social and Cultural Perspectives in Nutrition. Englewood Cliffs, NJ: Prentice-Hall. A sociocultural analysis of food, with an emphasis on conceptual frameworks and methodological options.

Shue, Henry. (1996). Basic Rights: Subsistence, Affluence, and U.S. Foreign Policy, 2nd edition. Princeton, NJ: Princeton University Press. This new edition of a well-received book updates the author's thesis that justice requires developed nations to share their knowledge and wealth with the chronically malnourished nations.

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