Recommended Dietary Allowances 10th Edition (1989) / Chapter Skim
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Energy
Energy
Pages 24-38
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From page 24... ...
In children and pregnant or lactating women the energy requirement includes the energy needs associated with the deposition of tissues or secretion of milk at rates consistent with good health (WHO, 19851. For groups, recommencled energy allowances represent the average needs of individuals.
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From page 25... ...
. Most food composition tables list physiologically available energy values based on digestibility trials of specific foods conducted by Atwater (Merrill and Watt, 1955~.
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From page 26... ...
Physical Activity For most people, the second largest component of total energy expenditure is the energy expended in physical activity. In the past, estimates of energy requirements were based in part on the different physical activity levels associated with different occupations.
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From page 27... ...
Incleed, for many Americans, increasing energy expenditure through activity may be a more effective way of maintaining health, including desirable body weight, than reduction in energy intake. Increased activity promotes fitness and allows a more generous intake of food, which makes for easier attainment of RDA levels of nutrients.
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From page 28... ...
Energy requirement can be estimated, albeit imprecisely, if the typical activity pattern is known. An average daily "activity factor" can be calculated using the values in Table 3-2 for different activities, weighted by the time engaged in such activities.
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From page 29... ...
would almost certainly have less muscle mass and might lack the physique to perform heavy physical work efficiently (Garrow and Blaza, 1982~. Thus, differences in energy requirement are due both to pattern of activity and the body composition that results from that ~ .
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From page 30... ...
The lean body mass of infants and young children contains a greater proportion of metabolically active organs than in adults. In adults, skeletal muscle, which has a lower rate of resting metabolism, is a major component of the lean body mass.
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From page 31... ...
Adjustment will need to be greater for persons who are both large and active. Weight may be used as a basis for adjusting energy allowances for different body sizes, provided the individuals are not appreciably liver or under median weights for height within a given age and sex category (see Table 2-1 in Chapter 2)
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From page 32... ...
, energy allowances may need to be slightly increased wherever persons are required to be physically active in extreme heat. With the above exceptions, no adjustment in energy allowance appears to be needed to compensate for change in climate, apart from climatic effects on physical activity patterns.
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From page 33... ...
1.70 1.67 1.67 1.60 1.50 1.67 1.60 1.60 1.55 1.50 The energy allowance for persons beyond age 50 is 1.5 x REE. This assumes continued light-to-moderate activity, which should be encouraged in the interest of maintaining muscle mass and wellbeing.
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From page 34... ...
Lactation Energy requirements for lactation are proportional to the quantity of milk produced. The average energy content of human milk from well-nourished mothers is about 70 kcal/100 ml (WHO, 1985~.
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From page 35... ...
The new estimates, 95 kcal and 84 kcal/kg at the respective age periods, based on expenditure plus storage, can be taken as equal to dietary requirement if the metabolizable energy value of foods consumed (human milk, formula, beikost) is estimated correctly.
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From page 36... ...
Allowances for other age groups are adjusted to reflect typical activity patterns in the United States ~ ~- ~ 1 1 1 ~ Those for older girls and boys are based on a predicted activity factor of 1.7 at 11 years of age and a decrease to the adult light to moderate activity value of 1.6 by age 15 in girls and age 19 in boys. COMPARISON OF RDA AND REPORTED INTAKES Energy intakes of children as reported in both the 1977-1978 Nationwide Food Consumption Survey (USDA, 1984)
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From page 37... ...
1988. Resting metabolic rate and body composition of healthy Swedish women during pregnancy.
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From page 38... ...
1989. Body fat mass and basal metabolic rate in Dutch women before, during, and after pregnancy: a reappraisal of energy cost of pregnancy.
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