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Estimating human energy requirements
2 Sachs, D. P. Smoking habits of pulmonary physicians. New England Journal of Medicine 309:799, 1983. 3 Marr, T., B. Shannon, and G. B. Spanier. Nutrition education for grades 7-12: The perspective of Pennsylvania teachers and administrators. Journal of Nutrition Education 12:148-52, 1980. 4 Consumer and Food Economics Institute. Agricultural Research Service. Nutritive value of foods. Home and Garden Bulletin No. 72. Washington, DC, 1971, 41 pp. 5 Agricultural Research Service. United States Department of Agriculture. Nutritive value of American foods in common units, by C. F. Adams. Agriculture Handbook No. 456. Washington, DC, 1975, 291 pp. 6 Food and Nutrition Board. National Research Council. National Academy of Sciences. Recommended dietary allowances. 9th ed. Washington. DC, 1980. 185 pp.
7 Hansen, R. G., and B. W. Wyse. Expression of nutrient allowance per 1,000 kilocalories. Journal of the American Dietetic Association 76:223-27, 1980. 8 U.S. Department of Health. Education, and Welfare. Public Health Service. Health Resources Administration. Dietary intake and biochemical findings. Preliminary findings of the first Health and Nutrition Examination Survey, United States 1971-1972. DHEW Publication No. (HRA) 7. Rockville, MD. 1974, p . 37. 9 U.S. Department of Agriculture. Science and Education Administration. Food and nutrient intakes of individuals in 1 day in the United States, Spring, 1977. Nationwide Food Consumption Survey 1977-1978. Preliminary Report No.2 . Washington. DC, 1980, p. 90.
ESTIMATING HUMAN ENERGY REQUIREMENTS An accurate prediction of a person's energy requirements is important for preventing and treating obesity as well as for avoiding overfeeding critically ill hospitalized patients. Energy requirement calculations are based upon estimating energy losses, of which basal energy expenditure and physical activity are the two main components. Because the exact energy expended from normal physical activity is so tedious to calculate, basal energy expenditure is usually multiplied by a predetermined factor to estimate the amount of physical activity. Therefore. predicted basal energy figures serve as the cornerstone for estimating total energy needs. In the United States, the Harris-Benedict equation, developed in 1919. is the most widely used formula for estimating basal energy expenditure. However, in 201 studies of healthy men and women, Daly and co-workers (American Journal of Clinical Nutrition 42 :1170-74, 1985) found that this equation overestimated basal energy expenditure by 10 to 15%. Intrasubject differences, climatic factors, the level of physical activity, body composition, and the nature of ingested foods have all changed since the original Harris-Benedict study . The influence of such factors on the results of studies on human energy expenditures and requirements is unknown .
CALCIUM ABSORPTION AND LACfOSE INTOLERANCE Increasingly, osteoporosis has been observed among lactase-deficient individuals. This increased incidence may be because lactose-intolerant individuals avoid consuming milk products because of the symptoms produced after their ingestion. or because lactose malabsorption has a deleterious effect on calcium absorption. Previously, researchers observed that lactase-deficient persons can absorb lactose more efficiently from yogurt than from milk because the bacteria in yogurt produce lactase, which "predigests" the yogurt's lactose. Recently. Smith and colleagues (American Journal of Clinical Nutrition 42: 1197-200, 1985) wanted to determine whether such bacterial lactose digestion could enhance calcium absorption in lactase-deficient individuals. They compared calcium absorption from milk and yogurt in twelve healthy volunteers, seven of whom were lactase-deficient. The investigators found that lactase-deficient participants and controls absorbed calcium equally well from both yogurt and milk. Although this study found no apparent differences in calcium absorption from milk versus yogurt, yogurt remains an excellent source of dietary calcium for lactose-intolerant persons because the yogurt bacteria digests some of the lactose in the yogurt, thus allowing a larger portion of the product td be consumed without producing adverse physiological reactions . 220
JOURNAL OF NUTRITION EDUCATION
VOLUME 18
NUMBER 5
1986
7 Hansen, R. G., and B. W. Wyse. Expression of nutrient allowance per 1,000 kilocalories. Journal of the American Dietetic Association 76:223-27, 1980. 8 U.S. Department of Health. Education, and Welfare. Public Health Service. Health Resources Administration. Dietary intake and biochemical findings. Preliminary findings of the first Health and Nutrition Examination Survey, United States 1971-1972. DHEW Publication No. (HRA) 7. Rockville, MD. 1974, p . 37. 9 U.S. Department of Agriculture. Science and Education Administration. Food and nutrient intakes of individuals in 1 day in the United States, Spring, 1977. Nationwide Food Consumption Survey 1977-1978. Preliminary Report No.2 . Washington. DC, 1980, p. 90.
ESTIMATING HUMAN ENERGY REQUIREMENTS An accurate prediction of a person's energy requirements is important for preventing and treating obesity as well as for avoiding overfeeding critically ill hospitalized patients. Energy requirement calculations are based upon estimating energy losses, of which basal energy expenditure and physical activity are the two main components. Because the exact energy expended from normal physical activity is so tedious to calculate, basal energy expenditure is usually multiplied by a predetermined factor to estimate the amount of physical activity. Therefore. predicted basal energy figures serve as the cornerstone for estimating total energy needs. In the United States, the Harris-Benedict equation, developed in 1919. is the most widely used formula for estimating basal energy expenditure. However, in 201 studies of healthy men and women, Daly and co-workers (American Journal of Clinical Nutrition 42 :1170-74, 1985) found that this equation overestimated basal energy expenditure by 10 to 15%. Intrasubject differences, climatic factors, the level of physical activity, body composition, and the nature of ingested foods have all changed since the original Harris-Benedict study . The influence of such factors on the results of studies on human energy expenditures and requirements is unknown .
CALCIUM ABSORPTION AND LACfOSE INTOLERANCE Increasingly, osteoporosis has been observed among lactase-deficient individuals. This increased incidence may be because lactose-intolerant individuals avoid consuming milk products because of the symptoms produced after their ingestion. or because lactose malabsorption has a deleterious effect on calcium absorption. Previously, researchers observed that lactase-deficient persons can absorb lactose more efficiently from yogurt than from milk because the bacteria in yogurt produce lactase, which "predigests" the yogurt's lactose. Recently. Smith and colleagues (American Journal of Clinical Nutrition 42: 1197-200, 1985) wanted to determine whether such bacterial lactose digestion could enhance calcium absorption in lactase-deficient individuals. They compared calcium absorption from milk and yogurt in twelve healthy volunteers, seven of whom were lactase-deficient. The investigators found that lactase-deficient participants and controls absorbed calcium equally well from both yogurt and milk. Although this study found no apparent differences in calcium absorption from milk versus yogurt, yogurt remains an excellent source of dietary calcium for lactose-intolerant persons because the yogurt bacteria digests some of the lactose in the yogurt, thus allowing a larger portion of the product td be consumed without producing adverse physiological reactions . 220
JOURNAL OF NUTRITION EDUCATION
VOLUME 18
NUMBER 5
1986