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The relationship between obesity in adolescence and early growth
The Journal o[ P E D I A T R I C S
35
The relationsln'p between obesity in adolescence and early growth This study reports similar birth weights o[ obese and nonobese adolescent girls. A t 1 year o[ age, though heights were similar, those who were obese at adolescence had gained weight more rapidly than those who remained at normal weight. The mean menarcheal ages of the obese and control groups were not different.
Felix P. Heald, M.D.,* and Richard J. Hollander, M.D. WASHINGTON,
D. C.
T H E N A T U R A L history of obesity in humans is being clarified as the result of recent studies. 1-4 Mullins 2 divides obese adults into 2 main groups. One consists of those adults whose obesity developed after puberty and the second, of those whose obesity developed during childhood or adolescence (obesity of juvenile onset). It is significant that the juvenile onset of obesity was found in one third of the obese ~idults. The logical question is the probability of juvenile obesity persisting into adult life. It is generally agreed now 1-4 that: (a) A high percentage of juvenile obesity persists into adult life (75 to 80 per cent) ; (b) the prognosis is worse for girls; (c) those who are obese as juveniles constitute approximately 50 per cent of the grossly obese adultsY From the Division of Adolescent Medicine,
Children'; Hospital o[ the District o[ Columbia,
and Department of Pediatrics, Georgetown University School of Medicine. This investigation was supported in whole by Public Health Service Research Grant A M 05554, from the National Institute o[ Arthritis and Metabolic Diseases. *Address, 2125--13th Street, N. W., Washington, D.C. 20009.
Much less, however, is known about the onset of obesity in infancy and early childhood. This is important to determine because of the possibility that factors conducive to excessive adiposity, whether metabolic or environmental, might be expressed early in the child's development. The present paper is a retrospective study of heights and weights of obese and nonobese adolescent girls to determine if a trend towards obesity is evident in the first year of life. In addition, it presents data on the effect of obesity on maturation using the menarche as the index.
METHODS AND MATERIALS The study (obese) group of 158 girls were selected by their attendance at a summer camp for obese girls.* A detailed camp medical form and physical examination were the basis for exclusion of any with known endocrinopathy. Ninety-four girls were used as the control group, 14 from a neighboring camp, and 80 from the National Cathedral *Camp Seascape, East Brewster, Mass.
36
Heald and Hollander
July 1965
w
T a b l e I. M e a n s ( X ) , m e a n differences ( d ) , a n d sample sizes (N) for obese ( O ) a n d control (C) groups
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16)
(I) Response types Present age Menarche Present weight Present height Birth weight Birth height Six month weight Six month height One year weight One year height Six month weight minus birth weight Six month height minus birth height One year weight minus birth weight One year height minus birth height One year weight minus six month weight One year height minus six month height
(II) X--o 14.999 + 1.8 12.262 + 1.2 174.690 + 30 5.311 + 0.2 7.044 + 1.2 19.924+- 1.6 16.710+- 2.6 26.034 +- 1.4 23.323 + 2.8 29.581 + 1.6 9.807 + 2.7
(llI) Xo 13.878 + 1.4 (yr.) 12.354 +- 1.7(yr.) 106.266 -+ 15.6 (lb.) 5.236-+ 0.3 (ft.) 7.188+- 0.9(lb.) 19.839-+ 1.5 (in.) 16.195-+ 2.1 (lb.) 25.720-'2 1.9 (in.) 21.877 + 3.0(lb.) 29.041-+ 2.2(in.) 9.123-+ 2.0(lb.)
(IV) d = Xo-Xc 1.121'* -.092 68.424 *~ .075** -.144 .085 .605 .314 1.446 ~ .540 .684
(V) No 158 141 157 156 151 112 58 48 59 45 57
(VI) N~. 94 65 94 93 87 72 57 50 56 49 57
6.456 +- 1.9
5.891 + 2.3 (in.)
.565
43
47
16.431 +- 2.8
14.845 +- 28 (lb.)
1.586 ~
57
56
9.881 + 2.2
9.323-+ 2.3(in.)
.558
40
43
6.479-+ 3.1
5.637-+ 2.6(lb.)
.842
51
49
3.500-+ 1.1
3.465-+ 1.5(in.)
.035
39
43
*Significant at the 5 per cent level.
School in Washington, D. C. A l t h o u g h d a t a on 18 a d d i t i o n a l controls were available, these were excluded as p r o b a b l y overweight on the basis of height-weight relationship. T h e socioeconomic stratum of both study a n d control groups was considered similar due to their selection from private camps a n d schools. T h e d a t a in T a b l e I are c o m p a t i b l e with this view since variability in the study a n d control groups is similar. T h e subjects were white Americans. Each girl was requested, with the assistance of her parents, to fill out a questionnaire a n d to supply all available records concerning her present age, height (nearest i n c h ) , weight (nearest o u n c e ) , a n d age of m e n a r c h e (nearest m o n t h ) . W e i g h t a n d height at birth, 6 months, a n d 1 year were obtained. I n h e r e n t in this m e t h o d of d a t a collection are i n a d e q u a t e records a n d estimations. W h e r e the d a t a were questionable or no inf o r m a t i o n was available, questions were to be unanswered (as requested in the questionnaires). Correlating evidence of obesity such as skin caliper measurements was not avail-
able. Therefore, a n unknown error exists in the obese a n d control group. All statistics for this comparison study are listed in Tables I a n d I I . T h e o r d i n a r y "t" test was utilized in the presence of "homogenous variance" while C o c h r a n ' s test s was a p p l i e d in the presence of "heterogeneous variance." RESULTS
T h e comparisons of the a r i t h m e t i c means ( T a b l e I ) between the study a n d control groups were found to be significantly different at the 5 p e r cent level for the c u r r e n t age, weight, a n d h e i g h t - - w e i g h t at one year a n d weight gained d u r i n g the first year ( C o l u m n IV, rows 1, 3, 4, 9, a n d 13). T h e current average weight of the obese group is 174.7 pounds c o m p a r e d to 106.3 p o u n d s for the control, a difference of 68.4 pounds ( T a b l e I, row 3). T h e c u r r e n t average height of the study group is 5.3 feet a n d that of the control group is 5.2 feet, a n actual difference of 0.075 feet ( T a b l e I, row 4). T h e average weight at 1 year ( T a b l e I,
Volume 67 Number 1
Relationship of obesity in adolescence and early growth
Table II. Standard error of the mean (S.E.) of obese (O) and control (C) groups
Response types ( 1) (2) (3) (4) (5) (6) (7) (8) (9) (10) ( 11 ) (12) (13) (14) (15)
Present age Menarche Present weight Present height Birth weight Birth height Six month weight Six month height One year weight One year height Six month weight minus birth weight Six month height minus birth height One year weight minus birth weight One year height minus birth height One year weight minus six
month weight (16) One year height minus six month height
{(S.E.)o !(S.E.)c .144 .097 2.394 .019 .095 .149 .346 .202 .365 .238 .352
.146 .216 1.613 .027 .101 .174 .274 .268 .400 .314 .259
.289
.329
.374
.372
.352
.347
.438
.365
.170
.234
row 9) for these groups is significantly greater than that of the control, 23.3 pounds versus 21.9 pounds, a difference of 1.445 pounds. T h e average weight gain from birth to 1 year (Table I, row 13) is also significantly greater for the obese group, the difference being 1.6 pounds greater in the obese group. Statistical analysis failed to reveal any difference between the groups for birth weight or weight gain when divided into six-month increments during the first year. There was also no difference in height at birth, at 6 months, or at 1 year. Last, the age at menarche for both groups was statistically the same. DISCUSSION
Bauer, in 1929, suggested that the birth weights of obese subjects were often higher than those of nonobese. Since then, conflicting evidence has appeared in the literature reviewed by Wolff ~ concerning higher birth weights of the obese. Mossberg T studied the earlier evidence favoring heavier birth weights of obese children and presents his own data to confirm this observation. How-
37
ever, the data of Bruch s and Wolff, ~ as well as this report, show no difference in birth weights between obese and nonobese subjects when compared as a group. Furthermore, when Wolff subdivided the birth weights according to extent of obesity attained during childhood, the mean birth weight of the more obese group was not significantly greater than that of the less obese as children. Bruch * and OreP observed, too, that newborn infants with unusually high birth weights become obese in only a small number of instances. T h e reasons for the discrepancies concerning birth weights of obese children are not clear. The appearance of obesity early in Iife is of considerable interest to investigators of the pathogenesis of obesity. The thesis in our laboratory is that an unknown proportion of obesity in childhood and adolescence may represent an inborn error in metabolism. The genetics of obesity has not been clearly defined and cannot be until a precise metabolic marker, which plays an etiologic role in the development of obesity, can be identified and so traced in families. T h e available evidence ~, 3, 5, ~ strongly suggests familial predisposition to obesity which is higher in obesity of juvenile onset than of adult onset. If inherited metabolic factors play a role in juvenile obesity, their expression should be manifest early in life. Immeran, 1~ in 1875, first pointed out the onset of obesity by the first year of life. This initial observation has not been confirmed. Mossberg's review of the literature and his own data 7 indicate two peaks for the onset of juveniIe obesity. These are ages 0 to 4 (years) and 7 to 1i (years). Our own data clearly indicate that obese adolescent girls, as a group, are already heavier at 1 year of life. These data do not clearly indicate fatness. It is reasonable to suppose that increased amounts of adipose tissue accounted for their heavier weight at l year since all of the subjects were obese as adolescents. This point can be resolved only by a prospective study in which actual measures are obtained. The effect of obesity on puberty has been
38
Heald and Hollander
previously investigated by others. T h e data indicate that increased fatness accelerates puberty. M e n a r c h e in adolescent girls is one precise indicator of maturation. O t h e r investigators 7, 11, 12 have shown that obese adolescent girls have an earlier menarche (1 year) than do nonobese girls. Although Garn's is data were derived from a healthy population not selected for adiposity, he was able to demonstrate that children who are fatter in late childhood achieve sexual maturity earlier. In contrast to the previous findings of others, our data show no significant difference in the mean menarcheal age of obese adolescent girls. There are 2 possible explanations for this discrepancy. T h e effect of higher socioeconomic class on the acceleration of maturation has been demonstrated. 14 Therefore, particular care must be observed in selecting the obese and control groups from the same socioeconomic class. The other possibility is the effect of time on mean menarcheal age. It has been shown that the mean menarcheal age has steadily decreased over the past 100 years at a rate of approximately 9 months per decade, is Control data on menarche obtained 10 years prior to the study group would be in error by 9 months and could account for most of the differences in mean menarcheal age in one report? ~ Finally, the mean menarcheal age of 12.3 years in the obese subjects and 12.3 years in the control group represents the earliest mean menarcheal age reported to the present time. SUMMARY
1. Retrospectively, the birth weights of obese adolescent girls were similar to those of a nonobese group of girls. 2. At the end of 1 year of life the group
July 1965
who eventually became obese had gained weight significantly more rapidly and were heavier than the nonobese population. Their heights were not significantly different. 3. T h e m e a n menarcheal age of the obese and control group was not statistically different. This is the earliest mean menarcheal age reported to date. The authors wish to express their appreciation to Dr. Herbert Sarett for his discussions which precipitated this study. REFERENCES
1. Haase, K. E., and Hosenfeld, H.: Zur Fettsucht im Kindersalter, Ztschr. Kinderh. 78: 1, 1956. 2. Mullins, A. G.: The prognosis in juvenile obesity, Arch. Dis. Childhood 33: 307, 1958. 3. Lloyd, J. K., Wolff, O. H., and Whelem, W. S.: Childhood obesity: A long term study of height and weight, Brit. M. J. 7: 145, 1961. 4. Abraham, A., and Nordsieck, M.: Relationship of excess weight in children and adults, Pub. Health Rep. 75: 263, 1960. 5. Anderson, R., and Bancroft, T.: Statistical theory in research, New York, 1952, McGrawHill Book Co., Inc., p. 82. 6. Wolff, O. H.: Obesity in childhood, Quart. J. Med. 24: 109, 1955. 7. Mossberg, H. O.: Obesity in children, Acta paediat. (suppl. 2) 35: 1, 1948. 8. Bruch, H.: Obesity in childhood, Am. J. Dis. Child. 58: 457, 1939. 9. Orel, H., cited by Bruch. s 10. Immeran, H., cited by Mossberg. z Obesity in children, Acta paediat. (suppl. 2) 35: 15, 1948. 11. Bruch, H.: Obesity in relation to puberty, J. P~OIAT~19: 365, 1941. 12. Quaade, Fleming: Obese children, Copenhagen, 1955, Danish Science Press, Ltd., p. 96. 13. Garn, S., and Haskell, J.: Fat thickness and developmental status in childhood and adolescence, Am. J. Dis. Child. 99: 746, 1960. 14. Kark, E.: Puberty in South African girls, South African J. Lab. & Clin. Med. 2: 84, 1956. 15. Tanner, J. M.: Growth at adolescence, Oxford, 1962, Blackwell Scientific Publications, p. 153.
35
The relationsln'p between obesity in adolescence and early growth This study reports similar birth weights o[ obese and nonobese adolescent girls. A t 1 year o[ age, though heights were similar, those who were obese at adolescence had gained weight more rapidly than those who remained at normal weight. The mean menarcheal ages of the obese and control groups were not different.
Felix P. Heald, M.D.,* and Richard J. Hollander, M.D. WASHINGTON,
D. C.
T H E N A T U R A L history of obesity in humans is being clarified as the result of recent studies. 1-4 Mullins 2 divides obese adults into 2 main groups. One consists of those adults whose obesity developed after puberty and the second, of those whose obesity developed during childhood or adolescence (obesity of juvenile onset). It is significant that the juvenile onset of obesity was found in one third of the obese ~idults. The logical question is the probability of juvenile obesity persisting into adult life. It is generally agreed now 1-4 that: (a) A high percentage of juvenile obesity persists into adult life (75 to 80 per cent) ; (b) the prognosis is worse for girls; (c) those who are obese as juveniles constitute approximately 50 per cent of the grossly obese adultsY From the Division of Adolescent Medicine,
Children'; Hospital o[ the District o[ Columbia,
and Department of Pediatrics, Georgetown University School of Medicine. This investigation was supported in whole by Public Health Service Research Grant A M 05554, from the National Institute o[ Arthritis and Metabolic Diseases. *Address, 2125--13th Street, N. W., Washington, D.C. 20009.
Much less, however, is known about the onset of obesity in infancy and early childhood. This is important to determine because of the possibility that factors conducive to excessive adiposity, whether metabolic or environmental, might be expressed early in the child's development. The present paper is a retrospective study of heights and weights of obese and nonobese adolescent girls to determine if a trend towards obesity is evident in the first year of life. In addition, it presents data on the effect of obesity on maturation using the menarche as the index.
METHODS AND MATERIALS The study (obese) group of 158 girls were selected by their attendance at a summer camp for obese girls.* A detailed camp medical form and physical examination were the basis for exclusion of any with known endocrinopathy. Ninety-four girls were used as the control group, 14 from a neighboring camp, and 80 from the National Cathedral *Camp Seascape, East Brewster, Mass.
36
Heald and Hollander
July 1965
w
T a b l e I. M e a n s ( X ) , m e a n differences ( d ) , a n d sample sizes (N) for obese ( O ) a n d control (C) groups
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16)
(I) Response types Present age Menarche Present weight Present height Birth weight Birth height Six month weight Six month height One year weight One year height Six month weight minus birth weight Six month height minus birth height One year weight minus birth weight One year height minus birth height One year weight minus six month weight One year height minus six month height
(II) X--o 14.999 + 1.8 12.262 + 1.2 174.690 + 30 5.311 + 0.2 7.044 + 1.2 19.924+- 1.6 16.710+- 2.6 26.034 +- 1.4 23.323 + 2.8 29.581 + 1.6 9.807 + 2.7
(llI) Xo 13.878 + 1.4 (yr.) 12.354 +- 1.7(yr.) 106.266 -+ 15.6 (lb.) 5.236-+ 0.3 (ft.) 7.188+- 0.9(lb.) 19.839-+ 1.5 (in.) 16.195-+ 2.1 (lb.) 25.720-'2 1.9 (in.) 21.877 + 3.0(lb.) 29.041-+ 2.2(in.) 9.123-+ 2.0(lb.)
(IV) d = Xo-Xc 1.121'* -.092 68.424 *~ .075** -.144 .085 .605 .314 1.446 ~ .540 .684
(V) No 158 141 157 156 151 112 58 48 59 45 57
(VI) N~. 94 65 94 93 87 72 57 50 56 49 57
6.456 +- 1.9
5.891 + 2.3 (in.)
.565
43
47
16.431 +- 2.8
14.845 +- 28 (lb.)
1.586 ~
57
56
9.881 + 2.2
9.323-+ 2.3(in.)
.558
40
43
6.479-+ 3.1
5.637-+ 2.6(lb.)
.842
51
49
3.500-+ 1.1
3.465-+ 1.5(in.)
.035
39
43
*Significant at the 5 per cent level.
School in Washington, D. C. A l t h o u g h d a t a on 18 a d d i t i o n a l controls were available, these were excluded as p r o b a b l y overweight on the basis of height-weight relationship. T h e socioeconomic stratum of both study a n d control groups was considered similar due to their selection from private camps a n d schools. T h e d a t a in T a b l e I are c o m p a t i b l e with this view since variability in the study a n d control groups is similar. T h e subjects were white Americans. Each girl was requested, with the assistance of her parents, to fill out a questionnaire a n d to supply all available records concerning her present age, height (nearest i n c h ) , weight (nearest o u n c e ) , a n d age of m e n a r c h e (nearest m o n t h ) . W e i g h t a n d height at birth, 6 months, a n d 1 year were obtained. I n h e r e n t in this m e t h o d of d a t a collection are i n a d e q u a t e records a n d estimations. W h e r e the d a t a were questionable or no inf o r m a t i o n was available, questions were to be unanswered (as requested in the questionnaires). Correlating evidence of obesity such as skin caliper measurements was not avail-
able. Therefore, a n unknown error exists in the obese a n d control group. All statistics for this comparison study are listed in Tables I a n d I I . T h e o r d i n a r y "t" test was utilized in the presence of "homogenous variance" while C o c h r a n ' s test s was a p p l i e d in the presence of "heterogeneous variance." RESULTS
T h e comparisons of the a r i t h m e t i c means ( T a b l e I ) between the study a n d control groups were found to be significantly different at the 5 p e r cent level for the c u r r e n t age, weight, a n d h e i g h t - - w e i g h t at one year a n d weight gained d u r i n g the first year ( C o l u m n IV, rows 1, 3, 4, 9, a n d 13). T h e current average weight of the obese group is 174.7 pounds c o m p a r e d to 106.3 p o u n d s for the control, a difference of 68.4 pounds ( T a b l e I, row 3). T h e c u r r e n t average height of the study group is 5.3 feet a n d that of the control group is 5.2 feet, a n actual difference of 0.075 feet ( T a b l e I, row 4). T h e average weight at 1 year ( T a b l e I,
Volume 67 Number 1
Relationship of obesity in adolescence and early growth
Table II. Standard error of the mean (S.E.) of obese (O) and control (C) groups
Response types ( 1) (2) (3) (4) (5) (6) (7) (8) (9) (10) ( 11 ) (12) (13) (14) (15)
Present age Menarche Present weight Present height Birth weight Birth height Six month weight Six month height One year weight One year height Six month weight minus birth weight Six month height minus birth height One year weight minus birth weight One year height minus birth height One year weight minus six
month weight (16) One year height minus six month height
{(S.E.)o !(S.E.)c .144 .097 2.394 .019 .095 .149 .346 .202 .365 .238 .352
.146 .216 1.613 .027 .101 .174 .274 .268 .400 .314 .259
.289
.329
.374
.372
.352
.347
.438
.365
.170
.234
row 9) for these groups is significantly greater than that of the control, 23.3 pounds versus 21.9 pounds, a difference of 1.445 pounds. T h e average weight gain from birth to 1 year (Table I, row 13) is also significantly greater for the obese group, the difference being 1.6 pounds greater in the obese group. Statistical analysis failed to reveal any difference between the groups for birth weight or weight gain when divided into six-month increments during the first year. There was also no difference in height at birth, at 6 months, or at 1 year. Last, the age at menarche for both groups was statistically the same. DISCUSSION
Bauer, in 1929, suggested that the birth weights of obese subjects were often higher than those of nonobese. Since then, conflicting evidence has appeared in the literature reviewed by Wolff ~ concerning higher birth weights of the obese. Mossberg T studied the earlier evidence favoring heavier birth weights of obese children and presents his own data to confirm this observation. How-
37
ever, the data of Bruch s and Wolff, ~ as well as this report, show no difference in birth weights between obese and nonobese subjects when compared as a group. Furthermore, when Wolff subdivided the birth weights according to extent of obesity attained during childhood, the mean birth weight of the more obese group was not significantly greater than that of the less obese as children. Bruch * and OreP observed, too, that newborn infants with unusually high birth weights become obese in only a small number of instances. T h e reasons for the discrepancies concerning birth weights of obese children are not clear. The appearance of obesity early in Iife is of considerable interest to investigators of the pathogenesis of obesity. The thesis in our laboratory is that an unknown proportion of obesity in childhood and adolescence may represent an inborn error in metabolism. The genetics of obesity has not been clearly defined and cannot be until a precise metabolic marker, which plays an etiologic role in the development of obesity, can be identified and so traced in families. T h e available evidence ~, 3, 5, ~ strongly suggests familial predisposition to obesity which is higher in obesity of juvenile onset than of adult onset. If inherited metabolic factors play a role in juvenile obesity, their expression should be manifest early in life. Immeran, 1~ in 1875, first pointed out the onset of obesity by the first year of life. This initial observation has not been confirmed. Mossberg's review of the literature and his own data 7 indicate two peaks for the onset of juveniIe obesity. These are ages 0 to 4 (years) and 7 to 1i (years). Our own data clearly indicate that obese adolescent girls, as a group, are already heavier at 1 year of life. These data do not clearly indicate fatness. It is reasonable to suppose that increased amounts of adipose tissue accounted for their heavier weight at l year since all of the subjects were obese as adolescents. This point can be resolved only by a prospective study in which actual measures are obtained. The effect of obesity on puberty has been
38
Heald and Hollander
previously investigated by others. T h e data indicate that increased fatness accelerates puberty. M e n a r c h e in adolescent girls is one precise indicator of maturation. O t h e r investigators 7, 11, 12 have shown that obese adolescent girls have an earlier menarche (1 year) than do nonobese girls. Although Garn's is data were derived from a healthy population not selected for adiposity, he was able to demonstrate that children who are fatter in late childhood achieve sexual maturity earlier. In contrast to the previous findings of others, our data show no significant difference in the mean menarcheal age of obese adolescent girls. There are 2 possible explanations for this discrepancy. T h e effect of higher socioeconomic class on the acceleration of maturation has been demonstrated. 14 Therefore, particular care must be observed in selecting the obese and control groups from the same socioeconomic class. The other possibility is the effect of time on mean menarcheal age. It has been shown that the mean menarcheal age has steadily decreased over the past 100 years at a rate of approximately 9 months per decade, is Control data on menarche obtained 10 years prior to the study group would be in error by 9 months and could account for most of the differences in mean menarcheal age in one report? ~ Finally, the mean menarcheal age of 12.3 years in the obese subjects and 12.3 years in the control group represents the earliest mean menarcheal age reported to the present time. SUMMARY
1. Retrospectively, the birth weights of obese adolescent girls were similar to those of a nonobese group of girls. 2. At the end of 1 year of life the group
July 1965
who eventually became obese had gained weight significantly more rapidly and were heavier than the nonobese population. Their heights were not significantly different. 3. T h e m e a n menarcheal age of the obese and control group was not statistically different. This is the earliest mean menarcheal age reported to date. The authors wish to express their appreciation to Dr. Herbert Sarett for his discussions which precipitated this study. REFERENCES
1. Haase, K. E., and Hosenfeld, H.: Zur Fettsucht im Kindersalter, Ztschr. Kinderh. 78: 1, 1956. 2. Mullins, A. G.: The prognosis in juvenile obesity, Arch. Dis. Childhood 33: 307, 1958. 3. Lloyd, J. K., Wolff, O. H., and Whelem, W. S.: Childhood obesity: A long term study of height and weight, Brit. M. J. 7: 145, 1961. 4. Abraham, A., and Nordsieck, M.: Relationship of excess weight in children and adults, Pub. Health Rep. 75: 263, 1960. 5. Anderson, R., and Bancroft, T.: Statistical theory in research, New York, 1952, McGrawHill Book Co., Inc., p. 82. 6. Wolff, O. H.: Obesity in childhood, Quart. J. Med. 24: 109, 1955. 7. Mossberg, H. O.: Obesity in children, Acta paediat. (suppl. 2) 35: 1, 1948. 8. Bruch, H.: Obesity in childhood, Am. J. Dis. Child. 58: 457, 1939. 9. Orel, H., cited by Bruch. s 10. Immeran, H., cited by Mossberg. z Obesity in children, Acta paediat. (suppl. 2) 35: 15, 1948. 11. Bruch, H.: Obesity in relation to puberty, J. P~OIAT~19: 365, 1941. 12. Quaade, Fleming: Obese children, Copenhagen, 1955, Danish Science Press, Ltd., p. 96. 13. Garn, S., and Haskell, J.: Fat thickness and developmental status in childhood and adolescence, Am. J. Dis. Child. 99: 746, 1960. 14. Kark, E.: Puberty in South African girls, South African J. Lab. & Clin. Med. 2: 84, 1956. 15. Tanner, J. M.: Growth at adolescence, Oxford, 1962, Blackwell Scientific Publications, p. 153.