Nancy F. Butte
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nents of basal metabolism, thermogenesis, physical activity and energy cost of growth [2] . Basal metabolism is defined as that energy ex- pended to maintain cellular and tissue process- es fundamental to the organism. The Schofield equations [3] to predict basal metabolic rate (BMR) are presented in table 1 . Thermic effect of feeding refers to the energy required for the ingestion and digestion of food and for the ab- sorption, transport and utilization of nutri- ents. The thermic effect of feeding amounts to about 10% of daily energy expenditure. Ther- moregulation can constitute an additional en- ergy cost when exposed to temperatures below and above thermoneutrality; however, clothing and behavior usually counteract such environ- mental influences. Physical activity is the most variable component of energy requirements, and entails both obligatory and discretionary physical activities. The energy cost of growth as a percentage of total energy requirements decreases from around 35% at 1 month to 3% at 12 months of age, and remains low until the pubertal growth spurt, at which time it in- creases to about 4% [2] .
Approaches to Estimating Energy Requirements
Energy requirements can be derived from TEE based on the factorial approach, measurements us- ing the DLW method or heart rate monitoring.
DLW is a stable (nonradioactive) isotope method that provides an estimate of TEE in free-living indi- viduals [4] . By the heart rate method, TEE is pre- dicted from the heart rate based on the nearly linear relationship between heart rate and oxygen con- sumption during submaximal muscular work [5] .
Energy Requirements of Infants
In the recent FAO/WHO/UNU recommendations [1] , the average energy requirements of infants were based upon the TEE and growth rates of healthy, well-nourished infants ( tables 2 , 3 ; fig. 1 , 2 ). In the FAO/WHO/UNU report, the median weight-for-age and monthly rates of weight gain of the WHO pooled breastfed data set were used to calculate energy requirements [6] . A prediction equation (1) for TEE was developed, based on
Table 1. Schofield equations for estimating BMR from weight (kilograms) [3] in children Under 3 years
Males Females
BMR (MJ/day) = 0.249 weight – 0.127 BMR (MJ/day) = 0.244 weight – 0.130
SEE = 0.293 SEE = 0.246 Males
Females
BMR (kcal/day) = 59.5 weight – 30.4 BMR (kcal/day) = 58.3 weight – 31.1
SEE = 70 SEE = 59 3–10 years
Males Females
BMR (MJ/day) = 0.095 weight + 2.110 BMR (MJ/day) = 0.085 weight + 2.033
SEE = 0.280 SEE = 0.292 Males
Females
BMR (kcal/day) = 22.7 weight + 504.3 BMR (kcal/day) = 20.3 weight + 485.9
SEE = 67 SEE = 70 10–18 years
Males Females
BMR (MJ/day) = 0.074 weight + 2.754 BMR (MJ/day) = 0.056 weight + 2.898
SEE = 0.440 SEE = 0.466 Males
Females
BMR (kcal/day) = 17.7 weight + 658.2 BMR (kcal/day) = 13.4 weight + 692.6
SEE = 105 SEE = 111 SEE = Standard error of estimation.
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longitudinal data on 76 healthy infants studied at 3-month intervals for the first 2 years of life [2, 7] :
TEE (MJ/day) =
–0.416 + 0.371 weight (kg) SEE = 0.456 TEE (kcal/day) =
–99.4 + 88.6 weight (kg) SEE = 109, (1) in which SEE is the standard error of estimation.
Assuming energy equivalents of protein (23.6 kJ/g or 5.65 kcal/g) and fat (38.7 kJ/g or 9.25 kcal/g), and body composition changes during infancy [8, 9] , energy deposition de- creases substantially during the first year of life from approximately 730 kJ/day (175 kcal/
day) at 0–3 months to 250 kJ/day (60 kcal/day) at 4–6 months and 85 kJ/day (20 kcal/day) at 7–12 months of age.
Table 2. Energy requirements of boys during the first year of life 2002 Institute of Medicine [15] 2004 FAO/WHO/UNU [1]
Age, months MJ/day kcal/day MJ/d ay kcal/day kJ/kg/day kcal/kg/day
0–1 1.975 472 2.166 518 473 113
1–2 2.372 567 2.387 570 434 104
2–3 2.393 572 2.494 596 397 95
3–4 2.293 548 2.380 569 343 82
4–5 2.494 596 2.546 608 340 81
5–6 2.699 645 2.674 639 337 81
6–7 2.795 668 2.730 653 329 79
7–8 2.971 710 2.845 680 330 79
8–9 3.121 746 2.936 702 330 79
9–10 3.318 793 3.058 731 335 80
10–11 3.418 817 3.145 752 336 80
11–12 3.531 844 3.243 775 337 81
Table 3. Energy requirements of girls during the first year of life 2002 Institute of Medicine [15] 2004 FAO/WHO/UNU [1]
Age, months MJ/day kcal/day MJ /day kcal/day kJ/kg/day kcal/kg/day
0–1 1.833 438 1.942 464 447 107
1–2 2.092 500 2.162 517 421 101
2–3 2.180 521 2.301 550 395 94
3–4 2.125 508 2.245 537 350 84
4–5 2.314 553 2.389 571 345 83
5–6 2.481 593 2.507 599 341 82
6–7 2.544 608 2.525 604 328 78
7–8 2.690 643 2.630 629 328 78
8–9 2.837 678 2.728 652 328 78
9–10 3.000 717 2.828 676 331 79
10–11 3.105 742 2.902 694 331 79
11–12 3.213 768 2.981 712 331 79
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 34–40 DOI: 10.1159/000360315
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Energy Requirements of Children and Adolescents
In the 2004 FAO/WHO/UNU report [1] , DLW and heart rate monitoring were used to predict the TEE of children and adolescents. TEE data on 801 boys and 808 girls aged 1–18 years were com- piled from Canada, Denmark, Italy, Sweden, The Netherlands, Brazil, Chile, Columbia, Guatemala and Mexico, from which prediction equations for TEE were developed for boys and girls [10] :
For boys:
TEE (MJ/day) = 1.298 + 0.265 weight (kg) – 0.0011 weight 2 (kg 2 ) SEE = 0.518
TEE (kcal/day) = 310.2 + 63.3 weight (kg) – 0.263 weight 2 (kg 2 ) SEE = 124 (2)
For girls:
TEE (MJ/day) = 1.102 + 0.273 weight (kg) – 0.0019 weight 2 (kg 2 ) SEE = 0.650
TEE (kcal/day) = 263.4 + 65.3 weight (kg) – 0.454 weight 2 (kg 2 ) SEE = 155 (3)
0 300 400 500 600
060 80 100 120 140
0 2 4 6 8 10 12
Energy requirements (kJ/kg/day) Energy requirements (kcal/kg/day)
Age (months) 1985 FAO/WHO/UNU 2004 FAO/WHO/UNU
0 300 400 500 600
060 80 100 120 140
0 2 4 6 8 10 12
Energy requirements (kJ/kg/day) Energy requirements (kcal/kg/day)
Age (months) 1985 FAO/WHO/UNU 2004 FAO/WHO/UNU
Fig. 1. 2004 FAO/WHO/UNU energy requirements for boys 0–12 months of age.
Fig. 2. 2004 FAO/WHO/UNU energy requirements for girls 0–12 months of age.
38 Butte Table 5. Energy requirements of girls 0–18 years of age, computed for active (Institute of Medi- cine) or moderate (FAO/WHO/UNU) physical activity level
2002 Institute of Medicine [15] 2004 FAO/WHO/UNU [1]
Age, years MJ/day kcal/day MJ/day kcal/day kJ/kg/day kcal/kg/day
1–2 3.6 864 3.6 850 335 80
2–3 4.5 1,072 4.4 1,050 339 81
3–4 5.8 1,395 4.8 1,150 322 77
4–5 6.2 1,475 5.2 1,250 310 74
5–6 6.5 1,557 5.6 1,325 301 72
6–7 6.9 1,642 6.0 1,425 289 69
7–8 7.2 1,719 6.5 1,550 280 67
8–9 7.6 1,810 7.1 1,700 268 64
9–10 7.9 1,890 7.7 1,850 255 61
10–11 8.3 1,972 8.4 2,000 243 58
11–12 8.7 2,071 9.0 2,150 230 55
12–13 9.1 2,183 9.5 2,275 218 52
13–14 9.5 2,281 10.0 2,375 205 49
14–15 9.8 2,334 10.2 2,450 197 47
15–16 9.9 2,362 10.4 2,500 188 45
16–17 9.9 2,368 10.5 2,500 184 44
17–18 9.8 2,336 10.5 2,500 184 44
Table 4. Energy requirements of boys 0–18 years of age, computed for active (Institute of Medi- cine) or moderate (FAO/WHO/UNU) physical activity level
2002 Institute of Medicine [15] 2004 FAO/WHO/UNU [1]
Age, years MJ/day kcal/day M J/day kcal/day kJ/kg/day kcal/kg/day
1–2 3.9 930 4.0 950 345 82
2–3 4.7 1,120 4.7 1,125 350 84
3–4 6.2 1,485 5.2 1,250 334 80
4–5 6.6 1,566 5.7 1,350 322 77
5–6 6.9 1,658 6.1 1,475 312 74
6–7 7.3 1,742 6.6 1,575 303 73
7–8 7.7 1,840 7.1 1,700 295 71
8–9 8.1 1,931 7.7 1,825 287 69
9–10 8.5 2,043 8.3 1,975 279 67
10–11 9.0 2,149 9.0 2,150 270 65
11–12 9.5 2,279 9.8 2,350 261 62
12–13 10.2 2,428 10.7 2,550 252 60
13–14 11.0 2,618 11.6 2,775 242 58
14–15 11.8 2,829 12.5 3,000 233 56
15–16 12.6 3,013 13.3 3,175 224 53
16–17 13.2 3,152 13.9 3,325 216 52
17–18 13.5 3,226 14.3 3,400 210 50
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 34–40 DOI: 10.1159/000360315
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During adolescence, sex differences in body size and composition are accentuated [11] . The energy cost of growth was based on mean rates of weight gain calculated from the WHO weight- for-age standards [12] . The composition of weight gained was assumed to be 10% fat with an energy content of 38.7 kJ/g (9.25 kcal/g), 20% protein with an energy content of 23.6 kJ/g (5.65 kcal/g), or equivalent to 8.6 kJ/g (2.1 kcal/g). The energy requirements of boys and girls aged 0–18 years are summarized in tables 4 and 5 and figures 3 and 4 .
Recommendations for Physical Activity A minimum of 60 min/day of moderate-intensity physical activity is recommended for children and adolescents [1] , although there is no direct experimental or epidemiological evidence on the minimal or optimal frequency, duration or inten- sity of exercise that promotes health and well- being of children and adolescents [13] . Regular physical activity is often associated with decreased body fat in both sexes and, sometimes, increased fat-free mass at least in males. Physical activity is
0 100 200 300 400 500 600
0 50 100 150
0 2 4 6 8 10 12 14 16 18
Energy requirements (kJ/kg/day) Energy requirements (kcal/kg/day)
Age (years) Light
Moderate Heavy
0 100 200 300 400 500 600
0 50 100 150
0 2 4 6 8 10 12 14 16 18
Energy requirements (kJ/kg/day) Energy requirements (kcal/kg/day)
Age (years) Light
Moderate Heavy
Fig. 4. 2004 FAO/WHO/UNU energy requirement of girls 1–18 years of age at 3 levels of habitual physical activity.
Fig. 3. 2004 FAO/WHO/UNU energy requirements of boys 1–18 years of age at 3 levels of habitual physical activity.
40 Butte
associated with greater skeletal mineralization, bone density and bone mass.
Energy requirements must be adjusted in ac- cordance with habitual physical activity. Torun [14] compiled 42 studies on the activity patterns of 6,400 children living in urban, rural, industri- alized and developing settings from around the world. The TEE of rural boys and girls was 10, 15 and 25% higher at 5–9, 10–14 and 15–19 years of age, respectively, than that of their urban coun- terparts. As part of the compilation of TEE values described above, physical activity level (PAL) val- ues were estimated by using measured or predict- ed BMR [10] . The Schofield equations for BMR [3] were used to predict PAL for children and ad- olescents if not provided in the original publica- tion. The average PAL (1.7) from these studies re- flects a moderate level of activity. To estimate the energy requirements of children with different levels of habitual physical activity, a 15% allow-
ance was subtracted or added to the average PAL to estimate light (PAL = 1.5) and vigorous (PAL = 2.0) levels of activity in the 2004 FAO/WHO/
UNU report.
Conclusions
• Energy requirements of infants, children and adolescents are defined as the amount of en- ergy needed to balance TEE at a desirable level of physical activity, and to support optimal growth and development consistent with long- term health [1]
• Even though energy requirements are also presented for varying levels of physical activi- ty, moderately active lifestyles are strongly en- couraged for children and adolescents to maintain fitness and health and to reduce the risk of overnutrition
11 Forbes GB: Human Body Composition:
Growth, Aging, Nutrition, and Activity.
New York, Springer, 1987.
12 World Health Organization: Measuring change in nutritional status. Geneva, World Health Organization, 1983.
13 Boreham C, Riddoch C: The physical activity, fitness and health of children.
J Sports Sci 2001; 19: 915–929.
14 Torun B: Energy cost of various physical activities in healthy children: activity, energy expenditure and energy require- ments of infants and children. Lau- sanne, International Dietary Energy Consultancy Group, 1990, pp 139–183.
15 Institute of Medicine: Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. Washington, National Academies Press, 2002.
References
1 FAO/WHO/UNU Expert Consultation.
Human energy requirements. Rome, World Health Organization, 2004.
2 Butte NF: Energy requirements of in- fants. Public Health Nutr 2005; 8: 953–
967.
3 Schofield WN, Schofield C, James WPT:
Basal metabolic rate: review and predic- tion, together with an annotated bibliog- raphy of source material. Hum Nutr Clin Nutr 1985; 39C:1–96.
4 Schoeller DA, van Santen E: Measure- ment of energy expenditure in humans by doubly labeled water method. J Appl Physiol 1982; 53: 955–959.
5 Berggren G, Christensen EH: Heart rate and body temperature as indices of met- abolic rate during work. Arbeitsphysio- logie 1950; 14: 255–260.
6 WHO Working Group on Infant Growth: An evaluation of infant growth.
Geneva, Nutrition Unit, World Health Organization, 1994, vol 94, pp 1–83.
7 Butte NF, Wong WW, Hopkinson JM, Heinz CJ, Mehta NR, Smith EO: Energy requirements derived from total energy expenditure and energy deposition dur- ing the first 2 years of life. Am J Clin Nutr 2000; 72: 1558–1569.
8 Butte NF, Hopkinson JM, Wong WW, Smith EO, Ellis KJ: Body composition during the first two years of life: an up- dated reference. Pediatr Res 2000; 47:
578–585.
9 de Bruin NC, Degenhart HJ, Gàl S, Wes- terterp KR, Stijnen T, Visser HKA: En- ergy utilization and growth in breast-fed and formula-fed infants measured pro- spectively during the first year of life.
Am J Clin Nutr 1998; 67: 885–896.
10 Torun B: Energy requirements of chil- dren and adolescents. Public Health Nutr 2005; 8: 968–993.
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 34–40 DOI: 10.1159/000360315
1 Specific Aspects of Childhood Nutrition
Key Words
Protein ã Amino acids ã Requirement ã Infants ã Children
Key Messages
• A diet must contain a balanced mixture of all amino acids
• This can most easily be achieved by daily ingestion of animal protein; an alternative is a complemen- tary mixture of plant proteins
© 2015 S. Karger AG, Basel
Introduction
Protein, derived from the Greek word proteos , which means ‘primary’ or ‘taking first place’, is the major structural component of all cells in the body. Proteins also function as enzymes, trans- port carriers and hormones, and their component amino acids are required for the synthesis of nu- cleic acids, hormones, vitamins and other impor- tant molecules.
The 20 α-amino acids which are part of pro- teins are classified based on their nutritional im-
portance into indispensable (essential) amino acids, conditionally indispensable (conditionally essential) amino acids and dispensable (nones- sential) amino acids ( table 1 ).
Protein in the body is in a dynamic state re- ferred to as protein turnover, which involves con- tinuous degradation to free amino acids and re- synthesis of new proteins. The free amino acids are also constantly degraded and oxidized to car- bon dioxide and nitrogenous end products, prin- cipally urea and ammonia. Oxidation is an irre- versible step and leads to so-called obligatory losses. Dietary protein is necessary to replenish these losses of amino acids to maintain protein homeostasis. Furthermore, in children, there is an increased need for dietary protein to allow new tissue growth.
The requirement of dietary protein is there- fore composed of two components: maintenance and growth. The requirement of protein in chil- dren and adults has earlier been analyzed in de- tail [1–3] , and that of individual amino acids is currently investigated but has not yet been de- fined by the WHO/FAO.
Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 41–45 DOI: 10.1159/000367868
1.3 Nutritional Needs