BASAL
METABOLIC
RATE
IN
OBESE
CHILDREN
With
a Note
on
the
Basal
Metabolic
Rate
in Dwarfs
By ALBERTA ILIFF, Ph.D., Hs.itRY H. GORDON, M.D., HELEN MCNAMARA, M.A.,
AND
W.
RANDAL BELL, M.D.De,tver and New York
I
T HAS been well established that obesity in adults is due primarily to an excessive intake of food and not to a disorder of heat production. Evidence for this view hasbeen recently summarized by Newburgh and Conn.1 The systematic studies of Bruch2
indicate that in children as well obesity is usually caused not by an endocrine or metabolic
disorder but rather by a functional disturbance of appetite regulation, usually of psychic
origin.
Although it is generally accepted that the basal metabolic rate is normal in adults with
obesity,8’ no such uniformity of opinion exists in the pediatric literature. On the
contrary, observers’ 2-14 with considerable experience in pediatric endocrine problems
have tended to agree with Bruch3 in the following statement: “The figures observed
and the correlations calculated lead to the conclusion that determinations of basal
metab-olism as ordinarily carried out
and
as conventionally
reported
are an untrustworthy
guide
when the clinician is seeking to estimate the part played by the thyroid in the pathogenesisof obesity. Calculation of the basal metabolic rate according to different standards
fur-nishes widely diverging results, none of which can be considered the correct one. The
basal metabolism of obese children should remain the object of clinical research until the
many known components which enter into its computation are better recognized and
understood.”
It is the purpose of this paper to present the results of 524 observations of the basal
metabolism of 348
obese
children.
Analyses
of these
results
indicate
that the confusion mentioned arises from errors in the choice of methods of calculation of the basalmeta-bolic rate. Furthermore, if our concept of “correctnesS” be conformity of the results with
the clinical
observations
that
there
is no metabolic
disorder
in obese
children, then useof the Child
Research
Council
surface
area-age
standards’5
yields
acceptable
findings.
SOURCE OF DATA
The children studied ranged in age from 6 to 15 years and consisted of two groups.
Three hundred ninety-five observations were made on 301 children who had been
re-ferred to the pediatric endocrine clinic of the New York Hospital because of obesity.
Their weights ranged from 20 to 150% above the mean weights for age of the normal
children in the Child Research Council study.’5 The remaining 129 observations were
made on 47 children who are members of the Child Research Council group and who
From the New York Hospital and Department of Pediatrics, Cornell University Medical College, New York, N.Y., and the Departments of Human Growth and Pediatrics of the University of Colo-rado Medical Center, Denver, Cob.
Presented at the Annual Meeting of the American Pediatric Society, Quebec, May 24, 1948. (Received for publication Feb. 17, 1949.)
- CR.C. Standerda Mayo Stande..d.
- -- Mayo Standards less tO per cent
.-Boys
O
-‘-0
2
4 6 8 tO t2 14 16Ac in Years
r
in the course of their development have come to be from 10 to 35% above the mean weights for age. The observations at the New York Hospital were made by trained tech-nicians using a Benedict-Roth apparatus in the routine basal metabolism laboratory of
the hospital. These children had no special instructions or treatment but received
cus-tomary tactful reassurance to help allay apprehension. The Child Research Council
chil-dren had had repeated determinations of the basal metabolism but this has been shown
to be without effect on the results obtained for these children.16 All Child Research Council determinations were made with a closed chamber.17
CHOICE OF A STANDARD FOR REFERENCE
It is generally accepted that age, height and weight will independently affect the
rate of basal oxygen consumption.’8 For example, individuals of the same height
C 4, C
C
ED 55
3
0-U)
50
3 45
&
‘A C
0
ED 35
()
FIG. 1. Comparison of Child Research Council and Mayo standards for cal/hr/sq. m. referred to age for basal metabolism of boys.
and age but of different weights will have widely different oxygen consumption.
Individuals of the same weight and age but of different heights will also use
oxygen at different rates, but the effect of the differences in height is not as striking as
that of differences in weight. Finally, individuals of different ages will have different rates of oxygen consumption when weight and height are kept constant. The most
satisfactory standard of reference for adults, i.e., one which permits comparison of
in-dividuals of widely different sizes or configuration, is one based on age and surface area.
This ordinarily is calculated from height and weight.’8 Whether the satisfactory use of a
surface area standard stems from valid physiologic reasons’8 or is fortuitous and dependent
on the accidental use of a physical standard of reference which approximates the 3/4
power of the weight’’ does not affect the considerations of this paper.
746 A. ILIFF, H. H. GORDON, H. MCNAMARA AND W. R. BELL
TABLE I
EXAMPLE OF EFFECT OF CHOICE OF STANDARD ON CALCULATED DEVIATION OF BASAL METABOLIC RATE
Patient 118 Male Age: 10 yrs.
Wt.: 59.5 kg. Ht. : 148 cm. Surface area: 1.52 sq. m.
Cal./hr. found: 56.1
Cal/hr/sq. m. found: 36.9
C.R.C. Mayo
Standardcal./hr./sq.m. 42.8 47.7
Percentage deviation (B.M.R.) - 14 -23
Duval
and
Iliffl5 yields an answer. It is seen that the Mayo standards’#{176} are approximately 10% higher than those of the Child Research Council. No obvious explanation isavail-able for this discrepancy but its effect on interpretation is presented in the simple example
cited in Table I. For this 10 year old boy, the findings of a deviation of minus 14%
would suggest to the physician that no hypometabolism existed, whereas a report of
minus 23% might suggest that hypothyroidism was contributing to the discrepancy
be-tween energy intake and output. Since it is not simple to decrease the food intake of an
obese child, any possibility that thyroid therapy may be indicated is usually received
favorably by patient, parent and physician. Unfortunately, the administration of thyroid
in customary therapeutic doses to an individual without hypothyroidism leads to no
eleva-tion of the basal metabolism. In the cited example, the failure of response to thyroid
therapy would lead one to discard the tentative diagnosis of hypothyroidism. The next
step would be to say that determinations of the basal metabolic rate are untrustworthy
guides. Actually, the use of the Child Research Council standards will prevent this
situa-tion from arising frequently.
NYH. C.R.C. Total
ISt.ncIaidl Standardi Standardi
.RL1Nayo1
______ICJIt4s,o1
p O0
80
D&M.R. Iowa.. than -15
N 60
T
0 BP4.R. betwesn -15 and +15
40
2: 8.M.R. highs.. than +15
No. of Tests 395
129
524
No. of Childpen 301 #{149} 47 348
140 120 I00 80 60 40 20
N.Y H. and CRC. Children
-- IStandard Deviation
I .,‘,
I. S .‘:-,
‘0
P.
..‘%80
‘I
2’”
:1:
-50 -40 -30 -20 -10 0 +10 20 +30 +40 +50
Basal Metabolic Rate for Calories per Hour per Centimeter Age
FIG. 3. Effect of degree of obesity on deviation of basal metabolic rate when ht.-age standard is used.
N.Y.
H. and C.R.C Childreno
Mean- - I Standard Deviation
-50 -40 -30 -20 -10 0
+,o
+20 +30 +40 +50Basal Metabolic Rate for Calories per Hour per Kilogram ‘ Age
FIG. 4. Effect of degree of obesity on deviation of basal metabolic rate when wt.-age standard is used.
-c C ED 8) 8) 0 -o C #{149}0 4.) ‘0 8) 0 C 0’ ED 4.) C 8) ‘a 4.) -c .!‘ 140 8)
3;
c 120 ED U 8) IO0 > 0 0 ‘V C 0 (0 > 8) 0 8) a, ED 4) C 8) ‘a748 A. ILIFF, H. H. GORDON, H. MCNAMARA AND W. R. BELL A summary of the results of the 524 observations is presented in Figure 2. A devia-tion of minus 15% has been arbitrarily used as the dividing line between individuals with
normal basal metabolic rates and those who might be suspect of hypometabolism. It is
seen that with the Child Research Council standards only 3% of the New York Hospital
children and 4% of the Child Research Council children became suspect. With the
Mayo standards, 28% of the New York Hospital and 33% of the Child Research Council
children would have been suspect. For the two groups of children, 3% had a greater
minus deviation than 15% from the Child Research Council standards and 29% had
such a deviation from the Mayo standards.
140 120 100 60 40 20 Pt
N.Y. H. and C.R.C. Children
1,
#{149}1: ‘I.
I. ‘#{149},. #{149}
I ..s .
‘a
I.
#{149} r, ‘S
#{149} I
‘I’
s. I#{149}#{149}fls‘Is #{149}#{149}‘ I
-50 -40 -30 -20 -10 0 #{247}10 +20 +30 +40 #{247}50
Basal Metabolic Rate for Calories per Hour per S9uare Meter”-Age
FIG. 5. Effect of degree of obesity on deviation of basal metabolic rate when surface area-age standard is used.
The use of the Child Research Council surface area-age standards yielded results which
conform with the generally accepted idea that hypometabolism is not present in the large
majority of patients with obesity. This satisfactory relationship was found for both boys
and girls at the different ages studied. Similar results have been reported by Mossberg.”
The relationship of the degree of obesity to the deviation in basal metabolic rate is
expressed in Figures 3, 4 and 5, using Child Research Council age standards based on
height, on weight, and on the combination of the two into surface area. It is seen that
only with the latter is the deviation unaffected by the degree of obesity. With either weight or height alone, distortions appear whose magnitude depends on the degree of the
obesity. It seems fair to conclude that a standard of reference such as surface area which
is based on a combination of weight and height will give less difficulty in clinical
inter-pretation of the results as determined for obese children.
At the risk of confusing the issue, we would like to add one point about the
tation of the basal metabolic rate in dwarfs. In Table II are presented the rates of four
proved hypothyroid dwarfs for comparison with six nonhypothyroid dwarfs. It is seen
that only two of the nine determinations on the nonhypothyroid dwarfs showed metabolic
rates of less than plus 10%. The remaining six ranged from plus 16 to 44%. For the
proved hypothyroid dwarfs, all were less than plus 10%, but only one was as low as
TABLE II
BASAL METABOLIC RATES OF 10 DWARFS
Deviation from Child Research Council Surface Area-Age Standard
Nonhypothyroid Hypothyroid
AK. + 3
J.B. +16
+27 +44 +7
P.McA. +17
M.McE. +30
EM. +27
P.N. +31
H.T. - 4
+ 6
G.C. -16
D.C. -4
PH. +1
± 0
-Total determinations: 9 Number below + 10%: 2
6 6
minus 16% . Use of a weight or height standard did not help clarify the interpretation.
Actually it would seem that when one finds a basal metabolic rate in a dwarf which is
not elevated above plus 10%, when referred to Child Research Council surface area-age
standard, one should suspect the possibility of hypothyroidism.
SUMMARY
An analysis of the results of 524 observations of the basal metabolism of 348 obese chil-dren is presented. Since only 3% of the basal metabolic rates were lower than minus 15% of the Child Research Council surface area-age standards, it is suggested that these
stand-ards can be used satisfactorily in the management of children with obesity. For reasons
which are not obvious these standards do not suffice for children with dwarfism.
REFERENCES
1. Newburgh, L. H., and Conn., J. W., Obesity, Physiol. Rev. 24:18, 1944.
2. Bruch, H., Obesity in childhood. I. Physical growth and development of obese children, Am. J. Dis. Child. 58:457, 1939.
3. Bruch, H., Obesity in childhood. II. Basal metabolism and serum cholesterol of obese children, Am. J. Dis. Child. 58:1001, 1939.
4. Bruch, H., Obesity in childhood. III. Food intake of obese children: Physiologic and psychologic aspects, Am. J. Dis. Child. 59:739, 1940.
5. Bruch, H., Obesity in childhood. IV. Energy expenditure of obese children, Am. J. Dis. Child. 60:1082, 1940.
6. Bruch, H., and Touraine, G., Obesity in childhood. V. Family frame of obese children, Psycho-som. Med. 2:141, 1940.
750 A. ILIFF, H. H. GORDON, H. McNAMARA AND W. R. BELL
8. Boothby, W. M., and Sandiford, I., Summary of basal metabolism data on 8,614 subjects with especial reference to normal standards for estimation of basal metabolic rate, J. Biol. Chem. 54:783, 1922.
9. Strouse, S., Wang, C. C., and Dye, M., Studies on metabolism of obesity: Basal metabolism, Arch.
mt.
Med. 34:275, 1924.10. Grafe, E., Metabolic Diseases and Their Treatment, translated by M. G. Boise, Philadelphia, Lea & Febiger, 1933.
1 1. Strang,
J.
M., and Evans, F. A., Energy exchange in obesity, J. Clin. Investigation 6:277, 1928.12. Talbot, N. B., Obesity in children, M. Clin. North American 29: 1217, 1945.
13. Wilkins, L., in discussion on Syndrome of ovarian agenesis and dwarfism, Am. J. Dis. Child. 72:456, 1946.
14. McCune, D. J., in discussion on Basal metabolism of children, Am. J. Dis. Child. 72:459, 1946. 15. Lewis, R. C., Duval, A. M., and Iliff, Alberta, Standards for basal metabolism of children from
2to 15 years of age, inclusive,
J.
Pediat. 23:1, 1943.16. Lewis, R. C., Duval, A. M., and Iliff, Alberta, Effect of repeated determinations on basal metabolism of children, Am.
J.
Physiol. 140:461, 1944.17. Lewis, R. C., Kinsman, G. M., and Iliff, Alberta, Basal metabolism of normal boys and girls from 2 to 12 years old, inclusive, Am. J. Dis. Child. 53:348, 1937.
18. Du Bois, E. F., Basal Metabolism in Health and Disease, Philadelphia, Lea & Febiger, 1936. 19. Kleiber, M., Body size and metabolic rate, Physiol. Rev. 27:511, 1947.
20. Boothby, W. M., Berkson, J., and Dunn, H. H., Studies of energy metabolism of normal in-dividuals: Standard for basal metabolism with nomogram for clinical application, Am. J. Physiol. 116:468, 1936.
-21. Mossberg, H. 0., Obesity in children: Clinical-prognostical investigation, Acta paediat. (supp. 2) 35:1, 1948.
SPANISH ABSTRACT
Proporcion
Metabolica
Basal
en Nilios
Obesos
con
Una
Nota
en Ia
Proporcion
Metabolica
Basal
en Enanos
Se presenta un an#{225}lisis de los resultados de 524 observaciones del metabolismo basal de 348 ni#{241}os obesos. Como solamente el 3% de las proporciones metab#{243}licas basales fueron m#{225}sbajas que menos 15% de las normas de edad y area de superficie del Consej de InvestigaciOn del Ni#{241}o(Child Re-search Council), se sugiere que se usen estas normas satisfactoriamente en el manejo de ni#{241}oscon obesidad. Por razones que no son obvias, estas normas no bastan por ni#{241}oscon enanismo.
