IT HAS been estimated that it takes on the average about seven years of time for findings from scientists' lab oratories to reach the general public. How much time it takes before nutritional findings are even partially implemented into an individual's food practices is anyone's guess!
What about menu planning in our homes and institutions? And in our community nutrition programs and cooking schools? How well do our menus rate as far as sound, up-to-date nutrition is concerned? Let us look at a few areas where science is increasingly pointing up significant relationships between diet and serious health problems.
Saturated fats and cholesterol intake as related to increased risk of coronary heart disease has been under investigation for decades, and scientific journals are replete with publications on the subject. Dr. Jeremiah Stamler, a pioneer in research into the relationship between diet and our epidemic of heart attacks, has recently written: "It is remarkable that the data from every major research approach epidemiologic, pathologic, clinical and animal research---all point to the key role of nutrition, particularly the saturated fat and cholesterol component of the diet, operating to influence the blood fats leading to mass production of severe atherosclerosis. As cholesterol concentration increases so does the risk." 1
Another area that urgently needs attention is the amount of refined carbohydrates, especially sugar, that is used. The relationship between sugar and dental caries, or sugar, because of its concentration as well as some metabolic effects, and obesity is established. Excessive sugar consumption is being implicated in coronary heart disease. Dr. John Judkin, University of London, who has been in the forefront in this line of research, found that men who have suffered heart attacks used twice as much sugar as men of similar age without heart problems.2 Although re search and debate in scientific circles continue as to the role of sugar in coronary heart disease, it is clear that a diet high in sugar and animal fats together combines to raise the level of fatty substances in the blood higher than either one alone.3
Studies show that atherosclerotic plaques begin forming very early in life. Beginning in the 40's, 50's, or 60's to make changes may be too late for prevention, since susceptibility starts building up in the second decade of life.4 Of course, diet is not the whole answer to avoiding heart attacks, but it is one very important part of the whole answer, and we now know that the earlier you start on a proper diet, the better.
The total amount of refined carbohydrates consumed is emerging as a serious health problem. The concern involves more than a loss of nutrients, especially a loss of trace nutrients an area that is actively being studied to day. It is the large loss of fiber that is increasingly becoming a matter of concern.
In terms of calorie sources we find that a large portion of the American diet is low in fiber. Recent studies have suggested that people whose diet is rich in fiber have low blood cholesterol levels. In India, male volunteers ate 8 oz. of chickpeas (Bengal gram), consuming 1/2 oz. of fiber daily. Even while eating a high-fat diet (5 oz. butter fat per day), they had a marked reduction of serum cholesterol from 206 mg. to 160 mg./100 ml. 5 Twenty-one Dutch volunteers were fed 4.4 oz. per day of rolled oats, and in only three weeks their serum cholesterol level was lowered from 250 mg. to 223 mg./100 ml.6
The mechanisms by which fiber exerts a cholesterol-lowering effect involve the bile acids. People on a highfiber diet excrete more bile acids, and more sterols. This appears to prevent bile acid reabsorption as well as cholesterol absorption and reabsorption.
The amount of fiber in the diet is being investigated by several researchers who believe there is a link between low-fiber diets and colon cancer. One factor appears to be that if digesting material contains any carcinogen, it be comes more concentrated in the intestine if little bulk is eaten. In addition, the intestinal transit time is significantly increased so that the material stays in contact with the intestinal wall much longer. Burkitt reported transit times on diets differing in fiber: 35 hours in African villagers on high-fiber diets and 89 hours in English boarding school boys on low-fiber diets.7 Another possible relationship between fiber content and colon cancer is in regard to altering the bacterial flora that degrade or modify bile acids, resulting in possible cancer-producing products. 8
Although current research findings do not indicate that sugar, white flour, and refined cereal products are direct causes of colon cancer, their extensive use, however, has resulted in a drastic reduction in fiber in the American diet. There is considerable evidence that as a consequence we have lost a most important dietary factor to protect against cancer of the colon and rectum as well as several other intestinal disorders and possibly also coronary heart disease.
Nutrition research more and more is indicating the necessity to seriously review our recipes and evaluate our menus and our menu-planning practices. Not only must this be done in the home but it is also an important aspect to be considered in planning community nutrition programs and cooking schools. It is also especially challenging to those responsible for the food service in schools and colleges. It is time to check not only for the saturated fat and cholesterol content but the quantity of refined carbohydrates as well. How often are we using refined grain products sweet rolls, light graham breads and rolls, spaghetti, noodles, macaroni, and refined breakfast foods, either hot or cold? How often do we use desserts high in calories, saturated fats, and sugar? What about the frequency of using so-called "hidden sugar" products?
It is time we emphasize an increased use of whole-grain breads and cereals, legumes, nuts, and fruits (more often in their whole form rather than juices for more fiber and other nutrients), and vegetables. It is time to significantly de-emphasize the use of sugar, high-fat dairy foods such as Cheddar cheese, sour cream, and ice cream as well as eggs.
Food habits are resistant to change. But the challenge to move along in line with what research shows is best for health must be met.
FOOTNOTES
1. Jeremiah Stamler, cited in Atherosclerosis (New York: Medcom, Inc., 1974).
2. J. Judkin, et al., "Sugar Intake and Myocardial Infarction," Amer. J. Clin. Nutr., 20:503, 1967.
3. M. A. Antar, et al., "Interrelationship Between the Kinds of Dietary Carbohydrate and Fat in Hyperlipoproteinemic Patients," Atherosclerosis, 11:191, 1970.
4. Robert B. McGandy, et al., "Dietary Regulation of Blood Cholesterol in Adolescent Males: a Pilot Study," Am. J. Clin. Nutr., 25:61, 1972.
5. K. S. Mathur, M. A. Khan, and R. D. Sharma, "Hypocholesterolaemic Effect of Bengal Gram: a Long-Term Study in Man," Br. Med. J., 1:30, 1968.
6. High Trowell, "Fiber: a Natural Hypocholesteremic Agent," Am. J. Clin. Nutr., 25:444, 1972.
7. D. P. Burkitt, A. R. P. Walker, N. S. Painter, "Effect of Dietary Fiber on Stools and Transit Times, and Its Role in the Causation of Disease," Lancet, 2:1408, 1972.
8. D. P. Burkitt, "Epidemiology of Cancer of the Colon and Rectum," Cancer, 28:3, 1971.