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Further studies of the use of meat in the diet ofinfants and young children
F U R T H E R S T U D I E S OF T H E USE OF M E A T IN T H E D I E T O F I N F A N T S AND YOUNG C H I L D R E N
RUTH M. L.EVERTON, ProD., [~INCOI~N, N~B., GEORGE CLARK, M.I)., OMAHA, NFB., PAUL M. BANCROFT, M.D., aND ESTHER COPEMANr, H E use of meat in the diet of young infants is receiving considerable attention. McQuarrie and Ziegler 1 have used strained meat as a source of protein in a mineral-enriched meat formula designed for children who for some reason are not able to tolerate milk. Sisson and co-workers ~ have evaluated the use of strained meat in the diets of premature infants. Balance studies of nitrogen, fat, calcium, phosphorus, and iron were conducted on eighteen premature infants from 12 to 50 days of age. The infants received a milk formula followed by the formula with one-third of the milk protein replaced by meat, or they received a formula of mineral-enriched meat and olive oil. Observations were made on changes in weight and growth, general clinical condition. The workers conclude, " M e a t protein is as well stools, hemoglobin, serum protein, .and consumed and utilized as milk protein by the premature infant and is, therefore, as safe and efficient a source of protein as milk. The fat absorption of the premature infant is not significantly altered when the milk fat in the diet is p a r t l y or wholly replaced by meat fat or meat fat and olive oil." The meat diet resulted in better iron
T
P u b l i s h e d w i t h t h e a p p r o v a l of t h e D i r e e t o r a s p a p e r No. 536, J o u r n a l Series, N e b r a s k a A g r i c u l t u r a l E x p e r i m e n t Station. T h e w o r k ~eas s u p p o r t e d in p a r t b y g r a n t s from the NationaI Live Stock and Meat Board, and Swift and Company.
761
B.S.,
LINCOLN,
NEB.
retention than the milk diet but the meat diet did not prevent the physiological fall in hemoglobin and total p r o t e i n in the blood. Andehnan and associates 3 found no significant difference in hemoglobin or red cell values of infants at 12 weeks of age who had received breast milk, formula, or formula plus meat. However, at 20 weeks of age the infants receiving the formula plus meat had a hemoglobin concentration higher than the infants on the other two regimes, and significantly greater than that of the infants on the formula alone. They state, " T h e data suggest that meat may contain some hemoglobin-producing substance which is not present in the cow's milk formula even when adequate iron is provided. I t appears to be a problem worthy of further study." Leverton and Ciark 4 reported on a preliminary study which showed that meat added to the formula of bottlefed infants beginning when they were 6 weeks old promoted the formation of hemoglobin and.red cells above that in infants who served as controls and received no meat. I t is now possible to report on the completed work which includes results on twenty-eight infants living in their own homes, and sixty infants and twenty-eight young children living in a child-care institution.
,762
THE
JOURNAI~
PROCEDURE
The plan of the study was to add meat to the diet of some of the subjeers and compare the r e s u l t s with those of control subjects who received no meat; or to have the subjects act as their own controls and eomp.are the results on the diet with and without added meat. T h e results were measured by determination of the hemoglobin and red cell content of the blood and b y clinical investigations. The subjects were grouped as follows: Group I included twenty-eight healthy infants who lived in their own homes and were pt'ivate patients of the pediatrician (P.M.B.). F o r thirteen of them he prescribed an ounce of strained beef to be given daily beginning when the infant was 8 weeks old and increased gradually to 2 ounces by the time the infant was 6 months old; this amount was continued until the infant was 9 to 12 months old. The m e a t was added to the f o r m u l a if one was used, or othe~eise fed by spoon. I t was dispensed by prescription and purchase records indicated that the infants received only about ha]f the a m o u n t prescribed. The other fifteen infants served as eontro!s and had no meat prescribed for them. A vitamin D concentrate was given to all the infants, and cereal, fruits, vegetables, and eggs were recommended at the usual ages for such additions. Group I I included sixty healthy infants in the child-care institution. They were on a formula of fresh milk with Dextri-Maltose, and received 25 rag. of aseorbie acid and a vitamin D concentrate daily. Forty-seven infants were p!aeed on the study, either .as controls or to receive meat when they were 6 or 8 weeks of age and then
OF
PEDIATRICS
were studied for eight weeks until they were 14 and 16 weeks old, respectively. Thirteen infants were placed on meat at 10 weeks of age and followed until they were 20 weeks old; they had no controls. The strained meat was mixed with the formula for each feeding. The amount of meat added was the quantity necessary to increase the protein content of each i n f a n t ' s formula 25 p e r cent; the amount varied front 24 to 30 Gin. daily. Veal, beef, pork, and ~amb were used; one variety was used each week and then the sequence was repeated. Tile Dextri-Maltose was decreased to compensate for the calories furnished b y the meat. Group I I I included twenty-eight children in the same institution who ranged in age f r o m 12 to 24 months and were called " t o d d l e r s . " They were studied for one month before the period of meat supplementation, during a four-month period of meat supplementation, and for one month afterward. Thus they served as their own controls. All the meals for three days of every week were analyzed to determine their nitrogen content. The standardized institution diet provided 44 Gm. of p r o t e i n per child. E v e r y child was served the same amount of food and ate everything served to him. When 100 Gin. of strained or diced meat were added daily (divided among the three meals) the portion of tile total, protein intake supplied by the institution diet dropped to 36 Gin. Thus the meat supplement resulted in a daily net increase of 12 Gm. o:e protein. The total daily protein intake was then 56 (~m. d u r i n g the fourmonth period of meat supplementation as compared with 44 (~m. before and after.
LEVERTON ET
AL. :
M E A T I N D I E T S O1~" I N F A N T S AND Y O U N G C H I L D R E N
A member of the research staff worked full time at the institution makia~g the formulas in which meat was included, taking samples of the toddlers' diets for nitrogen analysis, adding meat to their meals, and keeping' all records of illness, including colds. ttemoglobin and red cell values were determined on all subjeets immediately before the addition oE meat to their diets. Subsequent tests were made .at the intervals shown in Tables I and I I - - t h r e e months for the p r i v a t e patients, two and f o u r weeks f o r the infants and toddlers in the institution. In most instances duplicate determinations were made at each test. An electric eolorimeter was used for the determination of hemoglobin values. As with a n y s t u d y dealing with hum a n subjects, there were unavoidable irregularities. Three times as m a n y infants and toddlers were started on the study, either as controls or to receive meat, as ever completed it or can b e included in this report. I n the ease of the private patients m a n y were irregular in reporting to the pediatrid a n and occasionally the mother of an infant, who was considered a control subject, added meat to the child's diet on her own initiative and made it necessary to omit the child f r o m the study. I n the ease of the institution subjects, some were adopted or transferred to another department, while a few.deve]oped indications of physical abnormalities which kept t h e m f r o m being normal subjects. IIowever, significance is added to the results by reporting only on tile subjects who rigidly followed through the plan of the study.
763
RESULTS
I n Tables I and I I are shown the mean hemoglobin a n d red cell values of each of the three groups of subjects. The results are expressed in grams per cent and millions per cubic millimeter, respectively, and also in percentage of the initial value before the subjects were given meat or kept as controls. I f there was .an irregularity, sueh as failure to report to the pediatrician for a test, this percentage was based not on the mean initial value of all subjeets but only of those tested. I n Groups I and I I the hemoglobin a n d . r e d cell values of the infants who received meat inereased above those of subjects who served as controls and above the values at the beginning of the study. Group I, the infants in their own homes, did not show as much i m p r o v e m e n t b y three months of age as Group II, the infants at tile institution. However, the infants in Group I had higher initial values and received only half as much meat as the infants in Group II. The blood values of Group I I i , tlle toddlers, improved steadily during the f o u r months while meat was added to the diet, but dropped to the initial levels when the meat supplement was discontinue& I t m a y be considered significant that the blood values for subjects receiving m e a t never decreased below their initial values. Although the variability in blood values between subjeets and between times of testing was too great to have the differenees statistieally significant, the trend 6f the values was consistently in :favor of the meat supplementations.
764
THE JOURNAL OF PEDIATRICS
did the ]neat interfere with or supplant the milk intake. The ineidenee of colds was recorded for the meat-fed and control infants in Group l I during the eight weeks they were on the study. The meat-fed
There was no difference in growth, weight, a n d height of the meat and control groups although at the institution the meat groups gained weight slightly more uni%rmly. Stool records showed no abnormalities. I n no ease TABLE
'
GROUP
I.
MEAN
NO. OE SUBJECTS
BLOOD
VALUES
OF THE
IN~'ANTN
AGE AT i - SUB- " IIEMOBEGINSEQUENT GLOBIN NING TESTS GM, %
BED CELLS
M./C.~XM.
HEMOBED GLOBIN CELLS % OF INITIAL VALUE
months Group I. P r i v a t e patients Meat
2
13
3 6 9 Control
2
15
3 6 9
1].1 11.3 ]1.7 11.9 12.7 11.7
3.72 3.82 3.90 4.13 3.93 3.85
]00 103 105 111 ]00 98
4,00
100 102 105 107 100 92 92 93
11.7
3,98
1].8
]0.6 11.6 12.0 10.5 10.5 10.3 11.3 12.0 12.4 13.2 11.8 10.5 11.0 10.5 10.9 11.4 12.9 11.9 12.7 12.6
3.64 4.13 4.42 3.81 3,93 3.87 3.80 3,97 3.86 5.04 4.].5 4.11] 4.31 4.31 4.18 4.31 4.99 4.67 4.67 5.27
100 109 ]]3 100 100 98 100 106 110 117 100 89 93 92 100 105 118 109 117 316
100 ]13 121 100 103 102 100 105 102 133 100 99 99 105 100 103 119 112 112 126
]01
102
wee~s Group I L I n childcare i n s t i t u t i o n Meat
21
6 12 14
18
Control
0 12 14
3
Meat
8 10 12 16
5
Control
8 10 12 16
13
Meat
10 12 14 16 18 20
TABLE
II.
MEAN
BLOOD
rIME O~~ TESTS D u r i n g one m o n t h b e f o r e m e a t s u p p l e m e n t was added M onths on m e a t : 1 2 3 4 One m o n t h a f t e r m e a t supp l e m e n t was d i s c o n t i n u e d
VALUES
01," THE
HEMOGLOBIN GM. %
TWENTY-EIGHT
11.8
RED CELLS IVs 4,82
12.8 12.8 13.4 13.5 11.7
5,15 5.35 5.38 5.29 4.79
TOI)DLEIr
(GROUP
Ill)
I IIEMOGLOBIN I RED CELLS I % OE INITIAL VALUE 100 100
109 109 113 114 99
107 311 111 110 99
L E V E R T O N E T AL. :
M E A T I N D I E T S OF I N F A N T S A N D Y O U N G C H I L D R E N
infants averaged two colds for this period; no infant had more t h a n three or less t h a n one cold. The duration ranged f r o m one to three days and often the cold was no more t h a n a ease of "sniffles." The n u m b e r of colds among the control infants ranged f r o m three to six and averaged f o u r which lasted fronl two to six days. All the infants were kept in the same room with m a n y other infants not on the study. I n general the eribs of the meat-fed babies were kept along the outside wails under the large windows of the n u r s e r y where the t e m p e r a t u r e was lower and drafts were much greater than in the center of the room where the other cribs were kept. Colds among the toddlers were reduced also. The staff members stated that colds were frequent and lingering among these children beeause they played, ate, and slept together in the same rooms. I n the f o u r months (October through J a n u a r y ) of the meat s u p p l e m e n t there were only fourteen colds among twelve of the twenty-eight toddlers. These colds lasted two to three days arid none spread to the whole group. I n addition to the blood values and incidence of colds there were certain informative observations. The mothers of the infants in Group I were enthusiastic about t h e results of using meat. I n their opinions the infants had fewer colds (even when the family had colds), better sleep habits, and a p p e a r e d better satisfied than their other babies who had not had meat. A t the institution, records of erying, and comments of the nursing' staff indicated t h a t the babies who had meat routinely were more satisfied and slept better at night titan the controls. The
765
pediatrician (G. C.) in charge of the medical care for all the children considered that the babies were in a better physical condition as a result of receiving the meat supplement. DISCUSSION
These data demonstrate that meat is effective in promoting hemoglobin and red cell formation in the infant. The essentiality of iron for the production of hemoglobin is well known. There is also considerable evidence that protein, too, is needed for the formation of hemoglobin. Leverton and Marsh a found that their data on college women " . . . . emphasize the impot~cance and value of dietary factors other than iron in overcoming' the simple hypoehromic anemia prevalent among w o m e n . " L y n c h and Snively G report that " A n e m i a is as much due to laek of protein as to the lack of iron and that protein is essential to its e u r e . " Stare and Thorn ~ state, "Of the various substances known to be neeessary in hemoglobin formation, protein and iron are needed in the largest a m o u n t s . " Weech a n d coworkers s found that dogs on diets deficient in protein developed deficits in both erythrocytes and hemoglobin. Meat is recognized as an excellent souree of iron as well as protein of high quality, and the effect t h a t the meat had on the hemoglobin and red blood cell values of the infants on this s t u d y was no doubt due, in p a r t at least, to these nutrients. I t is possible that other known or unknown factors in meat were also involved. The fact t h a t the infants receiving a dietary supplement of meat had app r o x i m a t e l y one-half as m a n y colds as the control subjects, and t h a t the duration of the colds was reduced suggests
766
THE JOURNAL OF PEDIATRICS
t h a t t h e f e e d i n g of m e a t to i n f a n t s h e l p s to p r e v e n t a n d s h o r t e n t h e d u r a t i o n of colds. A s i m i l a r r e p o r t has been made by Lynch and Snively, 6 namely, that upper respiratory tract infections are frequent in hypoprot e i n e m i c c h i l d r e n , a c o n d i t i o n t h a t is a l l e v i a t e d b y t h e f e e d i n g of a d i e t cont a i n i n g a n a b u n d a n c e of p r o t e i n foods such a s meat, eggs, cheese, etc. The r e l a t i o n s h i p of p r o t e i n i n t a k e to a n t i b o d y f o r m a t i o n a n d to t h e o c c u r r e n c e of i n f e c t i o n s h a s been f i r m l y establ i s h e d b y t h e classic w o r k s of C a n n o n , 9 a n d M a d d e n a n d W h i p p l e 2 ~ T h u s the a d d i t i o n a l p r o t e i n s u p p l i e d to t h e d i e t of t h e i n f a n t s b y t h e m e a t c o u l d h a v e been r e s p o n s i b l e f o r t h e i r i n c r e a s e d r e s i s t a n c e to colds. SUMMARY T w e n t y - e i g h t i n f a n t s in t h e i r own homes, a n d s i x t y i n f a n t s a n d t w e n t y e i g h t " t o d d l e r s " in a c h i l d - c a r e instir a t i o n w e r e s u b j e c t s f o r a s t u d y of tile effect of tile a d d i t i o n of m e a t to the diet.
satisfied when t h e y r e c e i v e d the m e a t supp]ement. No a d v e r s e s y m p t o m s of a n y k i n d r e s u l t e d f r o m t h e a d d i t i o n of m e a t to the diets of c h i l d r e n even as y o u n g as 6 weeks, n o r d i d t h e m e a t i n t e r f e r e with milk consumption. O n tile basis of t h e f i n d i n g s t h e r e a p p e a r s to be a definite p l a c e f o r m e a t i n t h e d i e t of i n f a n t s a n d y o u n g children. The authors wish to express their appreciation for the cooperation of the mothers, and of the staff members of the institution. REFERENCES 1. NieQuarrie, I., and Ziegler, M. R. : Nutritlve Value of 3/Iineral-Enriched 3/[eat and Milk, Pediatrics 5: 210, 1950. 2. Sisson, T. t~. C., Emmel, A. F., and Filer, L. J., Jr.: 2Cleat in the Diet of Premature Infants, Pediatrics 7: 89, 1951. 3. Andelman, M. B., Gerald, P. S., Rambar, A. C., and Kagan, ]3. 3/i.: Effects of Early Feeding of Strained Meat to Prematurely ]3orn Infants, Pediatrics, in press. 4. Leverton, 1~., and Clark, G.: Meat in the Diet of Young
5.
6.
H e m o g l o b i n a n d r e d cell v a l u e s of t h e i n f a n t s who r e c e i v e d m e a t inc r e a s e d above those who s e r v e d as controls. T h e t o d d l e r s w e r e t h e i r own cont r o l s a n d t h e i r b l o o d v a l u e s rose during' a f o u r - m o n t h p e r i o d of m e a t supp l e m e n t a t i o n a n d d r o p p e d w h e n it was discontinued.
8.
T h e i n c i d e n c e of colds in the i n s t i t u t i o n was r e d u c e d a m o n g t h e m e a t - f e d i n f a n t s . A l l i n f a n t s were r e p o r t e d to have s l e p t b e t t e r a n d a p p e a r e d m o r e
10.
7.
9.
Infants~ J. A. M. A.
134: 1215, 1947. Leverton, R., and N~arsh, A.: One ttundred Studies of the Calcium, Phosphorus, Iron, and Nitrogen Metabolism and Requirement of Young Women, Agric. Expel Sta. Res. Bull. 125: 1942. Lynch, H. D., and Snively, W. D., Jr.: tIypoproteinosis of Childhood, J. A. M. A. 147: 115, 1951. Stare, F. J., and Thorn, G . W . : Protein Nutrition in Problems of N-edical Interest, J. A. M. A. 127: 1120, 1945. Weeeh, A. A., Wollstein, N., and Goettseh, E.: Nutritional Edema in Dog'. Development of Deficit in Erythrocytes and IIemoglobin on Diet Deficient in Protein, J. Clin. Investigation 16: 719, 1937. Cannon, P. R.: The Relationship of Protein Metabolism to Antibody Production and Resistance to Infection, Advances in Protein Chemistry 2: 135, 1945. 3gadden, S. C., and Whipple, G. H.: Plasma Proteins: Their Source, Produeand Utilization, Physiol. l~ev. 20: 194, 1940.
RUTH M. L.EVERTON, ProD., [~INCOI~N, N~B., GEORGE CLARK, M.I)., OMAHA, NFB., PAUL M. BANCROFT, M.D., aND ESTHER COPEMANr, H E use of meat in the diet of young infants is receiving considerable attention. McQuarrie and Ziegler 1 have used strained meat as a source of protein in a mineral-enriched meat formula designed for children who for some reason are not able to tolerate milk. Sisson and co-workers ~ have evaluated the use of strained meat in the diets of premature infants. Balance studies of nitrogen, fat, calcium, phosphorus, and iron were conducted on eighteen premature infants from 12 to 50 days of age. The infants received a milk formula followed by the formula with one-third of the milk protein replaced by meat, or they received a formula of mineral-enriched meat and olive oil. Observations were made on changes in weight and growth, general clinical condition. The workers conclude, " M e a t protein is as well stools, hemoglobin, serum protein, .and consumed and utilized as milk protein by the premature infant and is, therefore, as safe and efficient a source of protein as milk. The fat absorption of the premature infant is not significantly altered when the milk fat in the diet is p a r t l y or wholly replaced by meat fat or meat fat and olive oil." The meat diet resulted in better iron
T
P u b l i s h e d w i t h t h e a p p r o v a l of t h e D i r e e t o r a s p a p e r No. 536, J o u r n a l Series, N e b r a s k a A g r i c u l t u r a l E x p e r i m e n t Station. T h e w o r k ~eas s u p p o r t e d in p a r t b y g r a n t s from the NationaI Live Stock and Meat Board, and Swift and Company.
761
B.S.,
LINCOLN,
NEB.
retention than the milk diet but the meat diet did not prevent the physiological fall in hemoglobin and total p r o t e i n in the blood. Andehnan and associates 3 found no significant difference in hemoglobin or red cell values of infants at 12 weeks of age who had received breast milk, formula, or formula plus meat. However, at 20 weeks of age the infants receiving the formula plus meat had a hemoglobin concentration higher than the infants on the other two regimes, and significantly greater than that of the infants on the formula alone. They state, " T h e data suggest that meat may contain some hemoglobin-producing substance which is not present in the cow's milk formula even when adequate iron is provided. I t appears to be a problem worthy of further study." Leverton and Ciark 4 reported on a preliminary study which showed that meat added to the formula of bottlefed infants beginning when they were 6 weeks old promoted the formation of hemoglobin and.red cells above that in infants who served as controls and received no meat. I t is now possible to report on the completed work which includes results on twenty-eight infants living in their own homes, and sixty infants and twenty-eight young children living in a child-care institution.
,762
THE
JOURNAI~
PROCEDURE
The plan of the study was to add meat to the diet of some of the subjeers and compare the r e s u l t s with those of control subjects who received no meat; or to have the subjects act as their own controls and eomp.are the results on the diet with and without added meat. T h e results were measured by determination of the hemoglobin and red cell content of the blood and b y clinical investigations. The subjects were grouped as follows: Group I included twenty-eight healthy infants who lived in their own homes and were pt'ivate patients of the pediatrician (P.M.B.). F o r thirteen of them he prescribed an ounce of strained beef to be given daily beginning when the infant was 8 weeks old and increased gradually to 2 ounces by the time the infant was 6 months old; this amount was continued until the infant was 9 to 12 months old. The m e a t was added to the f o r m u l a if one was used, or othe~eise fed by spoon. I t was dispensed by prescription and purchase records indicated that the infants received only about ha]f the a m o u n t prescribed. The other fifteen infants served as eontro!s and had no meat prescribed for them. A vitamin D concentrate was given to all the infants, and cereal, fruits, vegetables, and eggs were recommended at the usual ages for such additions. Group I I included sixty healthy infants in the child-care institution. They were on a formula of fresh milk with Dextri-Maltose, and received 25 rag. of aseorbie acid and a vitamin D concentrate daily. Forty-seven infants were p!aeed on the study, either .as controls or to receive meat when they were 6 or 8 weeks of age and then
OF
PEDIATRICS
were studied for eight weeks until they were 14 and 16 weeks old, respectively. Thirteen infants were placed on meat at 10 weeks of age and followed until they were 20 weeks old; they had no controls. The strained meat was mixed with the formula for each feeding. The amount of meat added was the quantity necessary to increase the protein content of each i n f a n t ' s formula 25 p e r cent; the amount varied front 24 to 30 Gin. daily. Veal, beef, pork, and ~amb were used; one variety was used each week and then the sequence was repeated. Tile Dextri-Maltose was decreased to compensate for the calories furnished b y the meat. Group I I I included twenty-eight children in the same institution who ranged in age f r o m 12 to 24 months and were called " t o d d l e r s . " They were studied for one month before the period of meat supplementation, during a four-month period of meat supplementation, and for one month afterward. Thus they served as their own controls. All the meals for three days of every week were analyzed to determine their nitrogen content. The standardized institution diet provided 44 Gm. of p r o t e i n per child. E v e r y child was served the same amount of food and ate everything served to him. When 100 Gin. of strained or diced meat were added daily (divided among the three meals) the portion of tile total, protein intake supplied by the institution diet dropped to 36 Gin. Thus the meat supplement resulted in a daily net increase of 12 Gm. o:e protein. The total daily protein intake was then 56 (~m. d u r i n g the fourmonth period of meat supplementation as compared with 44 (~m. before and after.
LEVERTON ET
AL. :
M E A T I N D I E T S O1~" I N F A N T S AND Y O U N G C H I L D R E N
A member of the research staff worked full time at the institution makia~g the formulas in which meat was included, taking samples of the toddlers' diets for nitrogen analysis, adding meat to their meals, and keeping' all records of illness, including colds. ttemoglobin and red cell values were determined on all subjeets immediately before the addition oE meat to their diets. Subsequent tests were made .at the intervals shown in Tables I and I I - - t h r e e months for the p r i v a t e patients, two and f o u r weeks f o r the infants and toddlers in the institution. In most instances duplicate determinations were made at each test. An electric eolorimeter was used for the determination of hemoglobin values. As with a n y s t u d y dealing with hum a n subjects, there were unavoidable irregularities. Three times as m a n y infants and toddlers were started on the study, either as controls or to receive meat, as ever completed it or can b e included in this report. I n the ease of the private patients m a n y were irregular in reporting to the pediatrid a n and occasionally the mother of an infant, who was considered a control subject, added meat to the child's diet on her own initiative and made it necessary to omit the child f r o m the study. I n the ease of the institution subjects, some were adopted or transferred to another department, while a few.deve]oped indications of physical abnormalities which kept t h e m f r o m being normal subjects. IIowever, significance is added to the results by reporting only on tile subjects who rigidly followed through the plan of the study.
763
RESULTS
I n Tables I and I I are shown the mean hemoglobin a n d red cell values of each of the three groups of subjects. The results are expressed in grams per cent and millions per cubic millimeter, respectively, and also in percentage of the initial value before the subjects were given meat or kept as controls. I f there was .an irregularity, sueh as failure to report to the pediatrician for a test, this percentage was based not on the mean initial value of all subjeets but only of those tested. I n Groups I and I I the hemoglobin a n d . r e d cell values of the infants who received meat inereased above those of subjects who served as controls and above the values at the beginning of the study. Group I, the infants in their own homes, did not show as much i m p r o v e m e n t b y three months of age as Group II, the infants at tile institution. However, the infants in Group I had higher initial values and received only half as much meat as the infants in Group II. The blood values of Group I I i , tlle toddlers, improved steadily during the f o u r months while meat was added to the diet, but dropped to the initial levels when the meat supplement was discontinue& I t m a y be considered significant that the blood values for subjects receiving m e a t never decreased below their initial values. Although the variability in blood values between subjeets and between times of testing was too great to have the differenees statistieally significant, the trend 6f the values was consistently in :favor of the meat supplementations.
764
THE JOURNAL OF PEDIATRICS
did the ]neat interfere with or supplant the milk intake. The ineidenee of colds was recorded for the meat-fed and control infants in Group l I during the eight weeks they were on the study. The meat-fed
There was no difference in growth, weight, a n d height of the meat and control groups although at the institution the meat groups gained weight slightly more uni%rmly. Stool records showed no abnormalities. I n no ease TABLE
'
GROUP
I.
MEAN
NO. OE SUBJECTS
BLOOD
VALUES
OF THE
IN~'ANTN
AGE AT i - SUB- " IIEMOBEGINSEQUENT GLOBIN NING TESTS GM, %
BED CELLS
M./C.~XM.
HEMOBED GLOBIN CELLS % OF INITIAL VALUE
months Group I. P r i v a t e patients Meat
2
13
3 6 9 Control
2
15
3 6 9
1].1 11.3 ]1.7 11.9 12.7 11.7
3.72 3.82 3.90 4.13 3.93 3.85
]00 103 105 111 ]00 98
4,00
100 102 105 107 100 92 92 93
11.7
3,98
1].8
]0.6 11.6 12.0 10.5 10.5 10.3 11.3 12.0 12.4 13.2 11.8 10.5 11.0 10.5 10.9 11.4 12.9 11.9 12.7 12.6
3.64 4.13 4.42 3.81 3,93 3.87 3.80 3,97 3.86 5.04 4.].5 4.11] 4.31 4.31 4.18 4.31 4.99 4.67 4.67 5.27
100 109 ]]3 100 100 98 100 106 110 117 100 89 93 92 100 105 118 109 117 316
100 ]13 121 100 103 102 100 105 102 133 100 99 99 105 100 103 119 112 112 126
]01
102
wee~s Group I L I n childcare i n s t i t u t i o n Meat
21
6 12 14
18
Control
0 12 14
3
Meat
8 10 12 16
5
Control
8 10 12 16
13
Meat
10 12 14 16 18 20
TABLE
II.
MEAN
BLOOD
rIME O~~ TESTS D u r i n g one m o n t h b e f o r e m e a t s u p p l e m e n t was added M onths on m e a t : 1 2 3 4 One m o n t h a f t e r m e a t supp l e m e n t was d i s c o n t i n u e d
VALUES
01," THE
HEMOGLOBIN GM. %
TWENTY-EIGHT
11.8
RED CELLS IVs 4,82
12.8 12.8 13.4 13.5 11.7
5,15 5.35 5.38 5.29 4.79
TOI)DLEIr
(GROUP
Ill)
I IIEMOGLOBIN I RED CELLS I % OE INITIAL VALUE 100 100
109 109 113 114 99
107 311 111 110 99
L E V E R T O N E T AL. :
M E A T I N D I E T S OF I N F A N T S A N D Y O U N G C H I L D R E N
infants averaged two colds for this period; no infant had more t h a n three or less t h a n one cold. The duration ranged f r o m one to three days and often the cold was no more t h a n a ease of "sniffles." The n u m b e r of colds among the control infants ranged f r o m three to six and averaged f o u r which lasted fronl two to six days. All the infants were kept in the same room with m a n y other infants not on the study. I n general the eribs of the meat-fed babies were kept along the outside wails under the large windows of the n u r s e r y where the t e m p e r a t u r e was lower and drafts were much greater than in the center of the room where the other cribs were kept. Colds among the toddlers were reduced also. The staff members stated that colds were frequent and lingering among these children beeause they played, ate, and slept together in the same rooms. I n the f o u r months (October through J a n u a r y ) of the meat s u p p l e m e n t there were only fourteen colds among twelve of the twenty-eight toddlers. These colds lasted two to three days arid none spread to the whole group. I n addition to the blood values and incidence of colds there were certain informative observations. The mothers of the infants in Group I were enthusiastic about t h e results of using meat. I n their opinions the infants had fewer colds (even when the family had colds), better sleep habits, and a p p e a r e d better satisfied than their other babies who had not had meat. A t the institution, records of erying, and comments of the nursing' staff indicated t h a t the babies who had meat routinely were more satisfied and slept better at night titan the controls. The
765
pediatrician (G. C.) in charge of the medical care for all the children considered that the babies were in a better physical condition as a result of receiving the meat supplement. DISCUSSION
These data demonstrate that meat is effective in promoting hemoglobin and red cell formation in the infant. The essentiality of iron for the production of hemoglobin is well known. There is also considerable evidence that protein, too, is needed for the formation of hemoglobin. Leverton and Marsh a found that their data on college women " . . . . emphasize the impot~cance and value of dietary factors other than iron in overcoming' the simple hypoehromic anemia prevalent among w o m e n . " L y n c h and Snively G report that " A n e m i a is as much due to laek of protein as to the lack of iron and that protein is essential to its e u r e . " Stare and Thorn ~ state, "Of the various substances known to be neeessary in hemoglobin formation, protein and iron are needed in the largest a m o u n t s . " Weech a n d coworkers s found that dogs on diets deficient in protein developed deficits in both erythrocytes and hemoglobin. Meat is recognized as an excellent souree of iron as well as protein of high quality, and the effect t h a t the meat had on the hemoglobin and red blood cell values of the infants on this s t u d y was no doubt due, in p a r t at least, to these nutrients. I t is possible that other known or unknown factors in meat were also involved. The fact t h a t the infants receiving a dietary supplement of meat had app r o x i m a t e l y one-half as m a n y colds as the control subjects, and t h a t the duration of the colds was reduced suggests
766
THE JOURNAL OF PEDIATRICS
t h a t t h e f e e d i n g of m e a t to i n f a n t s h e l p s to p r e v e n t a n d s h o r t e n t h e d u r a t i o n of colds. A s i m i l a r r e p o r t has been made by Lynch and Snively, 6 namely, that upper respiratory tract infections are frequent in hypoprot e i n e m i c c h i l d r e n , a c o n d i t i o n t h a t is a l l e v i a t e d b y t h e f e e d i n g of a d i e t cont a i n i n g a n a b u n d a n c e of p r o t e i n foods such a s meat, eggs, cheese, etc. The r e l a t i o n s h i p of p r o t e i n i n t a k e to a n t i b o d y f o r m a t i o n a n d to t h e o c c u r r e n c e of i n f e c t i o n s h a s been f i r m l y establ i s h e d b y t h e classic w o r k s of C a n n o n , 9 a n d M a d d e n a n d W h i p p l e 2 ~ T h u s the a d d i t i o n a l p r o t e i n s u p p l i e d to t h e d i e t of t h e i n f a n t s b y t h e m e a t c o u l d h a v e been r e s p o n s i b l e f o r t h e i r i n c r e a s e d r e s i s t a n c e to colds. SUMMARY T w e n t y - e i g h t i n f a n t s in t h e i r own homes, a n d s i x t y i n f a n t s a n d t w e n t y e i g h t " t o d d l e r s " in a c h i l d - c a r e instir a t i o n w e r e s u b j e c t s f o r a s t u d y of tile effect of tile a d d i t i o n of m e a t to the diet.
satisfied when t h e y r e c e i v e d the m e a t supp]ement. No a d v e r s e s y m p t o m s of a n y k i n d r e s u l t e d f r o m t h e a d d i t i o n of m e a t to the diets of c h i l d r e n even as y o u n g as 6 weeks, n o r d i d t h e m e a t i n t e r f e r e with milk consumption. O n tile basis of t h e f i n d i n g s t h e r e a p p e a r s to be a definite p l a c e f o r m e a t i n t h e d i e t of i n f a n t s a n d y o u n g children. The authors wish to express their appreciation for the cooperation of the mothers, and of the staff members of the institution. REFERENCES 1. NieQuarrie, I., and Ziegler, M. R. : Nutritlve Value of 3/Iineral-Enriched 3/[eat and Milk, Pediatrics 5: 210, 1950. 2. Sisson, T. t~. C., Emmel, A. F., and Filer, L. J., Jr.: 2Cleat in the Diet of Premature Infants, Pediatrics 7: 89, 1951. 3. Andelman, M. B., Gerald, P. S., Rambar, A. C., and Kagan, ]3. 3/i.: Effects of Early Feeding of Strained Meat to Prematurely ]3orn Infants, Pediatrics, in press. 4. Leverton, 1~., and Clark, G.: Meat in the Diet of Young
5.
6.
H e m o g l o b i n a n d r e d cell v a l u e s of t h e i n f a n t s who r e c e i v e d m e a t inc r e a s e d above those who s e r v e d as controls. T h e t o d d l e r s w e r e t h e i r own cont r o l s a n d t h e i r b l o o d v a l u e s rose during' a f o u r - m o n t h p e r i o d of m e a t supp l e m e n t a t i o n a n d d r o p p e d w h e n it was discontinued.
8.
T h e i n c i d e n c e of colds in the i n s t i t u t i o n was r e d u c e d a m o n g t h e m e a t - f e d i n f a n t s . A l l i n f a n t s were r e p o r t e d to have s l e p t b e t t e r a n d a p p e a r e d m o r e
10.
7.
9.
Infants~ J. A. M. A.
134: 1215, 1947. Leverton, R., and N~arsh, A.: One ttundred Studies of the Calcium, Phosphorus, Iron, and Nitrogen Metabolism and Requirement of Young Women, Agric. Expel Sta. Res. Bull. 125: 1942. Lynch, H. D., and Snively, W. D., Jr.: tIypoproteinosis of Childhood, J. A. M. A. 147: 115, 1951. Stare, F. J., and Thorn, G . W . : Protein Nutrition in Problems of N-edical Interest, J. A. M. A. 127: 1120, 1945. Weeeh, A. A., Wollstein, N., and Goettseh, E.: Nutritional Edema in Dog'. Development of Deficit in Erythrocytes and IIemoglobin on Diet Deficient in Protein, J. Clin. Investigation 16: 719, 1937. Cannon, P. R.: The Relationship of Protein Metabolism to Antibody Production and Resistance to Infection, Advances in Protein Chemistry 2: 135, 1945. 3gadden, S. C., and Whipple, G. H.: Plasma Proteins: Their Source, Produeand Utilization, Physiol. l~ev. 20: 194, 1940.