Contemporary Nutrition u.s. Dietary Trends
Figure 1-Changes in per capita consumption of food energy, protein, fat and carbohydrate 1910-1973 (USDA)
% of 1909-13
and Implications 150
Willis A. Gortner The past four decades have $een a dramatic turnaround in the overt nutritional health problems experienc'ed in the U.S. earlier in this century. Although isolated instances of the classic nutritional deficiency diseases still exist, the major vitamin deficiency diseases which plagued our country in the 1920s and 1930s have been successfully eradicated. However, nutrition is a factor in some of the current U.S. health problems, such as obesity and coronary heart disease. . The major sources of data on diets of various U.S. population groups have been the studies conducted by the U.S. Department of Agriculture (USDA) and the Department of Health, Education, and Welfare (DH EW) . The DH EW data represent dietary intake information from the Survey of Preschool Children, the Ten State Survey and the HANES Survey. For the most part, the dietary intake information obtained in the DHEW Nutritional Status Surveys tends to confirm USDA's nationwide survey of food consumption . The only data allowing a review of long term diet trends for the U.S. as a whole are USDA Food Balance Sheets which measure consumption of f90d in the U.S.
.......
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75
Carbohydrate 50 1910
I '20
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Year % of 1909-13 Eggs
Fruits and vegetables
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Figure 2- Trends in United States eating habits (USDA)
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Meat, poultry. fish
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75
Cereal products
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The increased consumption of meat, poultry, fish, dairy products and eggs during this century has led to this protein shift.
containing foods, accompanied by a decreased fiber intake, is of concern to many health professionals,
Carbohydrate
Fat
20014.
Consumption of carbohydrate has declined during this century. The decreasing intake of carbohydrate was also accompanied by a shift in the nature of the carbohydrate as seen in Figure 3. Starch has dropped off at a much more rapid rate than the total carbohydrate during these six decades. The rather marked rise in total and refined sugars that occurred in the 1920s has (after a decline during World War II) been maintained in the years subsequent to this. The very marked decline in consumption of potatoes began to reverse itself some years ago as a result of innovations in proc~ssing and marketing and the introduction of dehydrated and frozen products. (Figure 2) A second major shift in the diet is in the marked decrease in consumption of flour and cereal grain products. The reduced consumption of these complex carbohydrate-
Americans have steadily been consuming more fat. Similarly, the increased amount of fat in our diets has been accompanied by a shift in the type of fat consumed. There has been only a small change in saturated fatty acids in the food supply during the past several decades. Polyunsaturated fatty acids (linoleic acid) increased modestly prior to 1940, and noticeably during the last 20 years (which relates to the increase in our consumption of edible oils, margarine and shortening) . Cholesterol intake currently appears to be only 10 percent above that in the United States diet at the turn of the century. During the past 25 years there has been a declining use of eggs, lard, butter and various dairy products, while meat consumption has increased. Thus, the cholesterol level has risen only slightly during this period. (Continued on next page)
Jourl"!al of the American Pharmaceutical Association
Vol. NS 17, No.1, January 1977
49
Nutrient Trends in the U.S. Food Supply The trends in consumption of calories, protein, fat and carbohydrate during the past 65 years are shown in Figure 1. As seen in this graph, calorie consumption has remained essentially constant.
Protein The proportion of calories derived from protein today is similar to that in 1910. Early In this century, about 50 percent of the protein came from grain and other vegetable sources and about 5Q percent from animal products. Today 70 percent of the protein consumed is of the more expensive animal variety. The shift in the nature of the protein consumed is reflected in the commodity consumption data shown in Figure 2. Willis A. Gortner, PhD, is Executive Officer of the American Institute of Nutrition, Bethesda, Maryland
I
Contemporary Nutrition
Percent u.s. RDA 220-
%of 1909-13 1SO
Vitamin C
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Refined sugar
180 Vitam in A
Sugars
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Starch
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Niacin Iron Calcium
so 00 1910
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5-Year Moving Average
Figure 3-Changes in per capita civilian consumption of sugars, starch, and carbohydrate 1910-1973 (USDA)
Enrichment Program 1941
20-
1910
'20
Figure 4- (at right) Nutrients available for per capita consumption per day in the United States, 1910-1974 (USDA)
Vitamin and Mineral Consumption Our consumption of key vitamins and minerals has not decreased during this century. Calcium, vitamin C, and vitamin A are at higher levels in our food supply than they were 65 years ago (Figure 4) . In 1941, four nutrients (iron, riboflavin, niacin and thiamine) were added to flour, resulting in a marked increase in the per capita availability of these nutrients. The enrichment of cereals has also added nutrients (primarily B vitamins and iron) to our food supply. Dietary Implications of Changing Consumption Patterns Study of food consumption patterns over the last 65 years has revealed some of the nutritional problems inherent in today's diet. Although calorie consumption has remained essentially constant over the past 65
References 1. Abraham , S. , Lowenstein, F.W., and Johnson, C.L.: Preliminary findings of the first health and nutrition examination survey, United Sta tes 1971-72: dietary intake and biochemical findings, Publication No. (HRA ) 74-1219-1 , Departmen t of Health, Education, and Welfare, Washington, D.C., 1974. 2. Agricu ltural Research Service: Household food consumption survey 1965-1966, Report s Nos. 1 to 18, United States Depa rtment of Agriculture, Washington, D.C., 1968- 1974.
years, it has been accompanied by a decrease in energy expenditure. This combination has been clearly implicated in the major health problem of obesity in our population. Many health and medical experts feel that the high incidence of coronary heart disease and similar conditions is related to a diet which is high in animal protein and its accompanying saturated fat and cholesterol. They recommend reduced consumption of calories, animal products and total fat. The reduced consumption of complex carbohydrates accompanied by a decreased intake of fiper is also of concern to many health professionals. In addition to its role as a bulking agent in the healthy intestine, some studies suggest that fiber can provide therapy for symptoms of diverticulosis and reduce serum cholesterol levels. The investigation of the relationship of dietary fiber to certain diseases such as cancer of the colon and coronary heart disease is still in its early
3. Clark , F.: Recent food consumption surveys and their uses, Federation Proc. 33:2270-2274, 1974. 4. Department of Health , Education, and Welfare: Ten state nutrition survey, 1968-70, Publication Nos. (HSM) 728130,72-8131 . 5. Feeley, R.M., Criner, P.E. , and Watt, B.K.: Cholesterol content of food s, J. Am. Dietet. Assoc. 61: 134- 149 , 1972. 6. Friend , B.: Nutrients in the U.S. food supply. a review of trend s 1909- 1913 to 1965, Am. J. Clin. Nutr. 20:907-914 , 1967. 7. Friend, B., and Marston, R. : Nutritional review, National
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stages. Further research is necessary before valid conclusions can be made. Hopefully, the data described in this paper can at least lead health professionals to sources of information dealing with food and nutrition that can be examined relative to the changes in vari ous diseases. This department of the Journal is intended to assist practicing pharmacists in fulfilling their responsibilities in health education and patient counseling. It provides concise, well-documented, objective literature reviews, prepared by recognized experts, on current topics concerning nutrition and health. Some of the topics are related to drug therapy. Contemporary Nutrition is reproduced or adapted with permission from a newsletter of the same name published by the Nutrition Department of General Mills, Inc. and edited by A. Elizabeth Sloan, PhD.
Food Situation (USDA) 150:26- 32 , 1974. 8. Friend, B., and Marston , R.: Nutritional review, National Food Situation (USDA ): No. 154, 25, (Nov) 1975. 9. Gortner, W.A.: Nutrition in the United States-1900 to 1974 , Cancer Research. 35:3246-3253, 1975. 10. Kelsay, J.L.: A compendium of nutritional status studies and dietary eva luation studies conducted in the United Sta tes, 1957- 1967. 11. Owen, G. M., Kram , K.M. , Garry, P.J., Lowe , J.W., and Lubin. A. H.: A study of nutritional status of preschool children in the United States, 1968- 1970, Pediatrics. 53.597- 646, 1974.