Postgraduate Medicine
ISSN: 0032-5481 (Print) 1941-9260 (Online) Journal homepage: http://www.tandfonline.com/loi/ipgm20
Nutrition and short stature David S. Weaver & George M. Owen To cite this article: David S. Weaver & George M. Owen (1977) Nutrition and short stature, Postgraduate Medicine, 62:6, 93-99, DOI: 10.1080/00325481.1977.11714703 To link to this article: http://dx.doi.org/10.1080/00325481.1977.11714703
Published online: 07 Jul 2016.
Submit your article to this journal
View related articles
Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipgm20 Download by: [Australian Catholic University]
Date: 26 August 2017, At: 07:21
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
• Nutritional problems may result in growth retardation and, eventually, shortness of stature. This article discusses sorne of the most common nutritional causes of growth retardation and presents an approach to clinical evaluation.
Slze for Age and Rate of Gain Short stature is often defined as a body length or height more than 2 SD below the mean length or height for age. In terms of a standard growth chart, short stature is a length or height below the fifth percentile (National Center for Health Statistics charts) or the third percentile (Children's Medical Center, Boston, anthropometrie charts). The percentile lines on these growth charts do not accurately express the rates of gain, since the 97th (or 95th) and third (or fifth) percentiles have been constructed as confidence intervals around the 50th percentile (the mean) and do not reflect the actual percentile limits of the data for rate of gain. Stature is a direct result of growth ofboth the axial (spine) and the appendicular (lower extremities) segments of the skeleton. While the growth in length or height of a typical child is clearly nonlinear, it can be divided into time segments during which the increments are essentiaily linear. Tanner and associates 1 have provided data on increments (gains per interval of time) in length or height which can be used to estimate whether a child's skeletal growth is normal (tables l and 2). It is possible for stature to be below the fifth percentile for age (ie, "short stature") and the rate of gain to be weil within the normal limits. This is particularly likely in infants and young children with low birth weight. A child whose stature is below the fifth percentile but whose rate of growth is weil within the normal range will, intime, catch up in terms of absolute stature, at least to the limits imposed by parental stature. 2 Therefore, while measurements plotted on a standard growth chart indicate how close to normal a child' s length or height is at a particular age, use of standards of incrementai growth enables a physician to detect a slow rate of growth before short stature develops. The length of time over which growth measurements are made is an important element in the evaluation of growth, with respect to both absolute stature and rate of gain. As minimum intervals between measurements for decisions about rate of
Vol. 62 • No. 6 • December 1977 • POSTGRADUATE MEDICINE
nutrition and short stature David S. Weaver, PhD George M. Owen, MD University of New Mexico Albuquerque
consider What may be the earliest indication of a nutritional cause of growth retardation? ls zinc important in the growth process? Why is use of skim milk inappropriate during the first year of lite?
93
nutrition and short s t a t u r e - - - - - - - - - - - - - - - - - - - - - - table 1. growth velocity, boys* Percent lie
Growth ln helght or length (cm/yr), age 6 moto 10 yr
6 mo 1 yr
2
4
3
5
6
7
8
9
10
97th
22.5
16.3 11.8 10.4 9.4
8.4
7.8
7.4
7.1
8.8
6.7
50th
18
12.6
8.9
7.9 7
6.4
6
5.8
5.5
5.3
5.2
3rd
13.5
9
5.8
5.4 4.8
4.5
4.3
4.2
4.1
3.7
3.6
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
*Adapted from Tanner and essoclates. 1
table 2. growth velocity, girls* Percent lie
Growth ln helght or length (cm/yr), age 6 mo to 8 yr 6 mo
1 yr
2
97th
23.5
18.3
12.1
50th
19
13.8
9
7.8
3rd
14.5
10
6
5.3
3 10.4
4
5
6
7
8
9.2
8.3
7.8
7.5
7.2
7
6.5
6.1
5.7
5.5
4.7
4.5
4.3
4.2
4
*Adapted from Tanner and assoclates. 1
gain, Fomon3 suggested at least 56 days for infants less than 5 months of age and at least three months for older infants. Tanner and associates 1 suggested at least a year of observations for toddlers and older children before a conclusion is reached, although they considered three months sufficient for inferences to be drawn.
Nutrltlonal Causes of Poor Gain or Shortness of Stature Once a significantly depressed rate of growth (below the fifth or tenth percentile) bas been confllliled or short stature bas been verified, what nutritional causes might be suspected in a child living in North America? Calorie malnutrition, mineral deficiencies, and vitamin deficiencies, whether primary or secondary, are at the top of the list. Severe deficiencies of calories, protein, vitamins, and minerais resulting in manifest marasmus, kwashiorkor, or rickets are easily diagnosed without evaluation of growth rate or laboratory tests. Energy needs-When the growth rate is marginal, subclinical nutritional deficiencies
94
should be considered. Evaluation of the diet, both qualitative! y and quantitatively, is an essential frrst step. Major attention should be given to ascertaining whether net energy intake is adequate to meet the infant's or child's needs for maintenance (basal), activity, and growth. Distribution of calories among carbohydrate, fat, and protein must be appropriate for age. Intake of protein may be adequate to meet minimal requirements, but if net energy provided from fat and carbohydrate is borderline, dietary prote in may be used as an energy source rather than as a source of amino acids for growth of new tissue. An example would be the use of skim milk during the frrst year of life, especially before 6 months of age. The use of skim milk at this age is clearly inappropriate in view of the fact that fat in human milk provides nearly half of the total energy intake in breast-fed infants. It is unlikely that a young infant would obtain an adequate energy intake if fed skim milk. This would be an example of a primary deficiency of a nutritional component (ie, an insufficient quantity of the component in the diet). The fat in human milk is better absorbed than that in cow's milk. Similarly, vegetable oil (notably, corn oil) in commercial infant formulas is better absorbed than is butterfat. Although whole cow's milk and commercial formulas as usually used are isocaloric, the net fat intake would be 15% to 20% greater in a 4-month-old infant consuming commercial formula than in an infant of the same age consuming an equal volume of who le cow' s milk. In an infant or a young child with recurrent gastroenteritis or intractable diarrhea, severe deficiency of intestinal lactase and relative intolerance to lactose may develop. Because lactose ordinarily provides 40% to 45% of the calories in a young infant's diet, the net energy intake may be substantially less than the apparent intake. Prote in needs-If the net intake of fat and carbohydrate is adequate to meet energy needs for maintenance (basal), activity, and
POSTOAADUATE MEDICINE •
December 19n • Vol. 62 • No. 6
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
growth, protein deficiency should be considered. Protein requirements are estimated to be about 1.5 gm/100 caVday during the firSt year oflife and about 1.2 gm/kg/day from age 1 year until the adolescent growth spurt begins. 3 Protein is provided largely by milk during the firSt year and is provided later by a combination of milk, other animal products (meat, egg, dairy products besides milk), and vegetables. After the firSt year, at least in the United States, quantity of protein is a more important consideration than is quality. Mineral needs-The list of minerais essential to growth is long and includes many which appear to be needed only in trace amounts. Three minerais-iron, zinc, and calcium-appear to have major effects on growth and have been investigated sufficiently that statements of mechanisms and requirements can be summarized. The most obvious consequence of iron deficiency is anemia, which, if not corrected, directly affects growth by reducing appetite and food intake. Fomon 3 recommended a daily intake of 7 to 8 mg of iron. Zinc, traditionally considered a trace mineral, recently was shown to have majoreffects on growth. 4 ln a study of zinc levels in hair, deficiency of the mineral was found to be much more common than bad been suspected. 5 Although dietary requirements for zinc have not been established, zinc must be considered a potentially powerful influence on growth. 6 Calcium metabolism bas been examined more fully than bas zinc metabolism. Suffident calcium is essential for normal skeletal development. Excessive intake of protein 7 or fat 8 causes calcium to be excreted in abnormally large amounts and cao lead to metabolic shortages which penalize bone development. Conversely, excessive calcium intake appears to lead to reduced fat absorption. 8 Ziegler and Fomon9 have provided estimates of dietary calcium requirements for infants. Phosphorus is metabolized in a delicate balance with calcium metabolism. The ratio of tissue phosphorus to tissue calcium in chil-
Vol. 82 • No. 6 • December 1977 • POSTQRADUATE MEDICINE
David S. Weaver
George M. Owen
Dr Weaver, formerly in the department of anthropology, Collage of Arts and Sciences, University of New Mexico, Albuquerque, is assistant professer of sociology and anthropology, Wake Forest University, Winston-Salem, North Carolina. Dr Owen, formerly professer of pediatries and director of the clinical nutrition program, University of New Mexico School of Medicine, is professer and director, human nutrition program, School of Public Health; professor of pediatries, School of Medicine; and fellow, Center for Human Growth and Development, University of Michigan, Ann Arbor.
dren is approximately 0.51:1. 3 An excessive intake of phosphorus can lead to calcium insufficiency, even though the dietary intake of calcium appears adequate. The effects on mineral metabolism of certain items of diet cannot be ignored. Binding of zinc, calcium, phosphorus, and iron by phytates in unleavened cereal products 10 bas been shown to contribute to mineral deficiencies. Binding of necessary minerais by other dietary acids may be discovered. Vitamin D needs-Intertwined with problems of calcium metabolism is vitamin D deficiency. White most fluid milk and commercial infant formulas are supplemented with vitamin D to provide at least the recommended daily allowance (400 lU), infants of low birth weight and children whose intake of milk is restricted because of economie reasons, cultural preferences, or suspected allergy often do not receive sufficient dietary vitamin D. Exposure of skin to sunlight al(continued on page 98)
95
nutrition and short s t a t u r e - - - - - - - - - - - - - - - - table 3. laboratory indicators of current dietary lntake and of nutritlonal statua of young child*
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
Dletary component
Determinations relatlng to
Commenta
Current intake
Nutritional status
Protein
Serum or urine ures nitrogen
Serum albumin
Value for ures nitrogen in serum or urine correlates reasonably weil with current net intake of protein if renal function is normal. Ures nitrogen value in serum
ISSN: 0032-5481 (Print) 1941-9260 (Online) Journal homepage: http://www.tandfonline.com/loi/ipgm20
Nutrition and short stature David S. Weaver & George M. Owen To cite this article: David S. Weaver & George M. Owen (1977) Nutrition and short stature, Postgraduate Medicine, 62:6, 93-99, DOI: 10.1080/00325481.1977.11714703 To link to this article: http://dx.doi.org/10.1080/00325481.1977.11714703
Published online: 07 Jul 2016.
Submit your article to this journal
View related articles
Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipgm20 Download by: [Australian Catholic University]
Date: 26 August 2017, At: 07:21
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
• Nutritional problems may result in growth retardation and, eventually, shortness of stature. This article discusses sorne of the most common nutritional causes of growth retardation and presents an approach to clinical evaluation.
Slze for Age and Rate of Gain Short stature is often defined as a body length or height more than 2 SD below the mean length or height for age. In terms of a standard growth chart, short stature is a length or height below the fifth percentile (National Center for Health Statistics charts) or the third percentile (Children's Medical Center, Boston, anthropometrie charts). The percentile lines on these growth charts do not accurately express the rates of gain, since the 97th (or 95th) and third (or fifth) percentiles have been constructed as confidence intervals around the 50th percentile (the mean) and do not reflect the actual percentile limits of the data for rate of gain. Stature is a direct result of growth ofboth the axial (spine) and the appendicular (lower extremities) segments of the skeleton. While the growth in length or height of a typical child is clearly nonlinear, it can be divided into time segments during which the increments are essentiaily linear. Tanner and associates 1 have provided data on increments (gains per interval of time) in length or height which can be used to estimate whether a child's skeletal growth is normal (tables l and 2). It is possible for stature to be below the fifth percentile for age (ie, "short stature") and the rate of gain to be weil within the normal limits. This is particularly likely in infants and young children with low birth weight. A child whose stature is below the fifth percentile but whose rate of growth is weil within the normal range will, intime, catch up in terms of absolute stature, at least to the limits imposed by parental stature. 2 Therefore, while measurements plotted on a standard growth chart indicate how close to normal a child' s length or height is at a particular age, use of standards of incrementai growth enables a physician to detect a slow rate of growth before short stature develops. The length of time over which growth measurements are made is an important element in the evaluation of growth, with respect to both absolute stature and rate of gain. As minimum intervals between measurements for decisions about rate of
Vol. 62 • No. 6 • December 1977 • POSTGRADUATE MEDICINE
nutrition and short stature David S. Weaver, PhD George M. Owen, MD University of New Mexico Albuquerque
consider What may be the earliest indication of a nutritional cause of growth retardation? ls zinc important in the growth process? Why is use of skim milk inappropriate during the first year of lite?
93
nutrition and short s t a t u r e - - - - - - - - - - - - - - - - - - - - - - table 1. growth velocity, boys* Percent lie
Growth ln helght or length (cm/yr), age 6 moto 10 yr
6 mo 1 yr
2
4
3
5
6
7
8
9
10
97th
22.5
16.3 11.8 10.4 9.4
8.4
7.8
7.4
7.1
8.8
6.7
50th
18
12.6
8.9
7.9 7
6.4
6
5.8
5.5
5.3
5.2
3rd
13.5
9
5.8
5.4 4.8
4.5
4.3
4.2
4.1
3.7
3.6
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
*Adapted from Tanner and essoclates. 1
table 2. growth velocity, girls* Percent lie
Growth ln helght or length (cm/yr), age 6 mo to 8 yr 6 mo
1 yr
2
97th
23.5
18.3
12.1
50th
19
13.8
9
7.8
3rd
14.5
10
6
5.3
3 10.4
4
5
6
7
8
9.2
8.3
7.8
7.5
7.2
7
6.5
6.1
5.7
5.5
4.7
4.5
4.3
4.2
4
*Adapted from Tanner and assoclates. 1
gain, Fomon3 suggested at least 56 days for infants less than 5 months of age and at least three months for older infants. Tanner and associates 1 suggested at least a year of observations for toddlers and older children before a conclusion is reached, although they considered three months sufficient for inferences to be drawn.
Nutrltlonal Causes of Poor Gain or Shortness of Stature Once a significantly depressed rate of growth (below the fifth or tenth percentile) bas been confllliled or short stature bas been verified, what nutritional causes might be suspected in a child living in North America? Calorie malnutrition, mineral deficiencies, and vitamin deficiencies, whether primary or secondary, are at the top of the list. Severe deficiencies of calories, protein, vitamins, and minerais resulting in manifest marasmus, kwashiorkor, or rickets are easily diagnosed without evaluation of growth rate or laboratory tests. Energy needs-When the growth rate is marginal, subclinical nutritional deficiencies
94
should be considered. Evaluation of the diet, both qualitative! y and quantitatively, is an essential frrst step. Major attention should be given to ascertaining whether net energy intake is adequate to meet the infant's or child's needs for maintenance (basal), activity, and growth. Distribution of calories among carbohydrate, fat, and protein must be appropriate for age. Intake of protein may be adequate to meet minimal requirements, but if net energy provided from fat and carbohydrate is borderline, dietary prote in may be used as an energy source rather than as a source of amino acids for growth of new tissue. An example would be the use of skim milk during the frrst year of life, especially before 6 months of age. The use of skim milk at this age is clearly inappropriate in view of the fact that fat in human milk provides nearly half of the total energy intake in breast-fed infants. It is unlikely that a young infant would obtain an adequate energy intake if fed skim milk. This would be an example of a primary deficiency of a nutritional component (ie, an insufficient quantity of the component in the diet). The fat in human milk is better absorbed than that in cow's milk. Similarly, vegetable oil (notably, corn oil) in commercial infant formulas is better absorbed than is butterfat. Although whole cow's milk and commercial formulas as usually used are isocaloric, the net fat intake would be 15% to 20% greater in a 4-month-old infant consuming commercial formula than in an infant of the same age consuming an equal volume of who le cow' s milk. In an infant or a young child with recurrent gastroenteritis or intractable diarrhea, severe deficiency of intestinal lactase and relative intolerance to lactose may develop. Because lactose ordinarily provides 40% to 45% of the calories in a young infant's diet, the net energy intake may be substantially less than the apparent intake. Prote in needs-If the net intake of fat and carbohydrate is adequate to meet energy needs for maintenance (basal), activity, and
POSTOAADUATE MEDICINE •
December 19n • Vol. 62 • No. 6
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
growth, protein deficiency should be considered. Protein requirements are estimated to be about 1.5 gm/100 caVday during the firSt year oflife and about 1.2 gm/kg/day from age 1 year until the adolescent growth spurt begins. 3 Protein is provided largely by milk during the firSt year and is provided later by a combination of milk, other animal products (meat, egg, dairy products besides milk), and vegetables. After the firSt year, at least in the United States, quantity of protein is a more important consideration than is quality. Mineral needs-The list of minerais essential to growth is long and includes many which appear to be needed only in trace amounts. Three minerais-iron, zinc, and calcium-appear to have major effects on growth and have been investigated sufficiently that statements of mechanisms and requirements can be summarized. The most obvious consequence of iron deficiency is anemia, which, if not corrected, directly affects growth by reducing appetite and food intake. Fomon 3 recommended a daily intake of 7 to 8 mg of iron. Zinc, traditionally considered a trace mineral, recently was shown to have majoreffects on growth. 4 ln a study of zinc levels in hair, deficiency of the mineral was found to be much more common than bad been suspected. 5 Although dietary requirements for zinc have not been established, zinc must be considered a potentially powerful influence on growth. 6 Calcium metabolism bas been examined more fully than bas zinc metabolism. Suffident calcium is essential for normal skeletal development. Excessive intake of protein 7 or fat 8 causes calcium to be excreted in abnormally large amounts and cao lead to metabolic shortages which penalize bone development. Conversely, excessive calcium intake appears to lead to reduced fat absorption. 8 Ziegler and Fomon9 have provided estimates of dietary calcium requirements for infants. Phosphorus is metabolized in a delicate balance with calcium metabolism. The ratio of tissue phosphorus to tissue calcium in chil-
Vol. 82 • No. 6 • December 1977 • POSTQRADUATE MEDICINE
David S. Weaver
George M. Owen
Dr Weaver, formerly in the department of anthropology, Collage of Arts and Sciences, University of New Mexico, Albuquerque, is assistant professer of sociology and anthropology, Wake Forest University, Winston-Salem, North Carolina. Dr Owen, formerly professer of pediatries and director of the clinical nutrition program, University of New Mexico School of Medicine, is professer and director, human nutrition program, School of Public Health; professor of pediatries, School of Medicine; and fellow, Center for Human Growth and Development, University of Michigan, Ann Arbor.
dren is approximately 0.51:1. 3 An excessive intake of phosphorus can lead to calcium insufficiency, even though the dietary intake of calcium appears adequate. The effects on mineral metabolism of certain items of diet cannot be ignored. Binding of zinc, calcium, phosphorus, and iron by phytates in unleavened cereal products 10 bas been shown to contribute to mineral deficiencies. Binding of necessary minerais by other dietary acids may be discovered. Vitamin D needs-Intertwined with problems of calcium metabolism is vitamin D deficiency. White most fluid milk and commercial infant formulas are supplemented with vitamin D to provide at least the recommended daily allowance (400 lU), infants of low birth weight and children whose intake of milk is restricted because of economie reasons, cultural preferences, or suspected allergy often do not receive sufficient dietary vitamin D. Exposure of skin to sunlight al(continued on page 98)
95
nutrition and short s t a t u r e - - - - - - - - - - - - - - - - table 3. laboratory indicators of current dietary lntake and of nutritlonal statua of young child*
Downloaded by [Australian Catholic University] at 07:21 26 August 2017
Dletary component
Determinations relatlng to
Commenta
Current intake
Nutritional status
Protein
Serum or urine ures nitrogen
Serum albumin
Value for ures nitrogen in serum or urine correlates reasonably weil with current net intake of protein if renal function is normal. Ures nitrogen value in serum
