. 19“4|" w — ,__— ,—__ =3 — — .——— I —- — — ,~_ ,—__ — — — , 7,—— _’ THE SOUL M RIEETABC LES-M CF TWO FRE-SCHC’CL CHELEREN Titcsis for H1: Degree of M. S. MICHIGAN STATE COLLEGE 5y wia Mona Harit 1937 ”db, :wimmBW-v; ' - ~ . ‘ , mg. . THE SODIUM METABOLISM OF TWO FEE-SCHOOL CHILDREN By Sylvia Mona figrtt Submitted in partial fulfillment of the requirements for the degree of 'Master of Science Department of Food and Nutrition Division of Home Economics Michigan State College 1957 THESiS TABLE OF CONTENTS Ptge Ind ex to Tables 0 O O O C O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O I O O O 0 iii Index to Grcphs O O O O O O O O O O O O O O C O O O O O O O O O O O O O O C O O I O O O O O O O O O O O O 0 iv I C IntI‘Od—LIC tion 0 O O C O O O O O O O O O I O O O O O O O O O O 0 O O O O O O O O O O O O O O 0 O O C 1 II. Experimental Procedure SUbjectS. O O O O O O O O O O O O O C 0 O O C C O O O O O O O O O O 0 O O O O O O O O O O O 2 Diet. 0 O O O O O O O O O O O C O O O O O O O O C O O O O O O O O O O O O O O O O O O O O O C O 5 SpeCirneI’lS. C O O O O O O O O O O O O O O O O O C O O O O O O O O O O O O O O 0 O O O O O C 7 III. Chemical Methods B—eVieXI¥Of Literal-tureOOOOOOOOOOOOOOCOOOOOOOOOOOOOCC 9 Chemical I‘l‘Ietl-IOd USBdOOIOOOOOOO...0.000.000.0000... 12 IV. Results and Discussion Sodium Metabolism Daily - Medium and High Protein DietSOOIOOOOOOOOOOOOOOO0.00000000000000000 18 Sodium Metabolism by Periods - Medium Protein DietOOOOOOOOOOOOOOOOCOOOOOOOOOOOO00.000.000.000... 25 Sodium Metabolism by Periods - High Protein ietOOOOOOOCOOOOOOOOOOOO0......0.00000IOOOOOOOO... 29 Comparison of Sodium and Chlorine Metabolism...... 55 V. smma.ry.........OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO... 58 VI. BibliOgI‘E—AgjhyOOOOOOOOOOOOOOOOOOOOOOOOOO0.000.000.0000... 41 H 'Teble II. III. IV. VII. VIII. IX. INDEX TO TAFLES Physical measurements of children at beginning and end Of eXIDeriInentOOOOIOOOOOOOCOOCOO...00...... Composition of the Medium Protein Diet............ Composition of the High Protein Diet.............. Per cent recovery on known solutions of a sodium saJ-t USiI—ig two IzlethOdSOOOOCOOOOOOO0......O0.0.0... Daily sodium balances............................. Daily sodium balances per kilogram of body weight. Correlation of sodium intake with daily and period excretion, absorption and retention............... Total sodium balances per period.................. Sodium balances per kilogram of body weight per periOd-OOCOCOIOOO'COOOOOOOOOOOOOOOOOIOOOOOOI00...... Correlation of sodium intake with period excre— tion, absorption and retention per kilogram of bOdy weight.OOOCOOOOOOOOOOOOOOOOOOOIOOOOOO00...... iii Page 14 19 20 22 24 27 Table II. III. IV. INDEX TO GRAPHS Sodium intake and urinary excretion................... SOdium intake and absorptionoooooooooooooooooooooooooo Intake and excretion of sodium and chlorine........... Intake and excretion of sodium and chlorine........... Retention of sodium and chlorine...................... iv 28 50 55 57 INTRODUCTION Literature records very few experiments on sodium balance and none at all under the conditions of the present study. In most of the reports dealing with sodium balance, the subjects were infants whose diet consisted chiefly of milk, or hospitalized adults whose kidney function was impaired. This paper presents a balance study of sodium on two pre-school boys. It is a portion of a larger experiment cover- ing.a period of forty-eight days and including calories, nitrogen and other minerals. The purpose of this study was to determine the sodium balance of pre—school children on a quantitative basis, to measure the effect of a high and low protein diet on the sodium metabolism in pre-school children, to observe the variations in excretion when the intake varied, to compare the sodium metabolism with that of chlorine, and finally to compare the utilization of sodium by the two subjects. -2- EXPERIKENTAL PROCEDURE Subjects The subjects used for this study were two boys D and B aged four*years and nine months and four years and seven months reSpectiveLy. During the eXperimental period both boys lived under the supervision of trained persons, in an apartment in the Home Economics Building. Their environmental conditions — meals, toilet habits, sleep, outdoor exercise and other activities were constantly supervised and carefully regulated. They attended the college nursery school and, therefore, were not denied the normal companionship of other children. Observations made of their be- havior during the study indicated they were mentally normal but not superior children. Physical and medical examinations showed them to be in good physical condition at the time of the study although there was some indication of their having had infantile rickets. “The children had lived nearly all their lives in an orphanage where their food habits had been carefully controlled and where their diet was thought to have been adequate for normal nutrition. Table I shows the height and weight of the two boys at the beginning and at the end of the eXperiment as compared with the WOodbury height-weight standards for children under six years of age. It indicates that the children were of average 8126. ’TS OF CHILDRED PHYSICAL MEASURELJh ND 3F EKPERIHEHT m1 AT BEGINHIEG LNB E * ror'*‘- . .* "1 *Varintions from §gbject jg AFQ1.11_ Height Weight avgggge veight mo. cm. kg. per cent D 59 109.7 17.5 -5.1 B 55 109.7 18.6 +2.5 B 57 111.0 19.1 4__.+2.4 The experiment covered forty-eight days during which time the boys had, first, a medium protein diet providing 5 grams of protein per kilogram of body weight for 12 preliminary and 21 collection days, and second, a high protein diet supplying 4 grams of protein per kilogram of body weight for the following 15 days. Calculations showed that both the medium and high protein diets met all the physiological needs of the children according to our present standards. Subject D received 4% grams of codliver oil** and B, 5 grams daily. _..Di 2 Tables II and III give the composition of the medium and high protein diets as calculated from standard tables. Skim milk was added and the amount of beef and eggs were increased to raise the protein content of the second diet. The variations * Woodbury, R. M., Heights and Weights of Children under Six Years of Age, U. S. Department of Labor, Children's Bureau.#87 Table XXXI page 76. **Prepared by E. L. Patch and Company, Boston, Massachusetts. .4. TABLE 11 00120017100 or was imizmiiraorait 3137* m “ PM” ‘ . Residue 1000 1- ‘eight Protein Calories Sodium. Chlorine Calcium. Hagnesium. Potasium. Phosphorous Sulphur Iron Acid: Base gms. gms. gms. gms. gms. gms. gms. gms. gms. gms. cc n/10 cc n/10 010 11 720 25.76 896.8 0.3672 0.7632 0.8680 0.0868 1.0296 0.6696' 0.2888 0.001728 129.6 22 85 6.03 66.6 0.0088 0.0877 0.0302 0.0050 0.0630 0.0810 0.0878 0.001350. 89.9 new beef 85 9.59 70.2 0.0805 0.0365 0.0058 0.0113 0.1625 0.1035 0.1098 0.001080 51.7 flhole Wheat bread 72 6.98 77.1 0.2837 0.8370 0.0360 0.0360 0.1898 0.1260 0.0868 0.001152 52.6 0866 Red ,arina 18 2,00 55.2 0.0117 0.0137 0.0081' 0.0085 0.0216 0.0761 0.0279 0.000900 17.3 Cooked potato 63 1.39 52.3 .0132 0.0239 0.0088 0.0176 0.2703 0.0365 0.0189 0.000819 37.8 Strained tomatoes 90 1.73 57-9 0.0155 0.0h95 0.0180 0.0090 0.2790 0.035L 0.0126 02001710 50.h " carrots 72 0.82 16.3 0.0727 0.0259 0.0212 0.0151 0.2066 0.0126 0.0158 0.000792 77.8 " prunes 90 0.89 62.5 0.0621 0.0153 0.0219 0.0895 0.9270 0.0553 0.0333 0.003800 156.0 " 2911632008 90 0.10 181.3 0.0099 0.0085 0.0063 0.0072 0.1183 0.0108 0.0058 0.000270 80.5 Lettuce 18 0.17 2.7 0.0038 0.0108 0.0060 0.0028 0.0875 0.0059 0.0020 0.000098 10.8 Strained orange juice 180 77.8 0.0188 0.0058 0 0522 0.0198 0.3276 0.0288 0.0162 0.000360 81.0 Sugar 18 72.0 ’ Butter 18 0.18 138.8 0.1818 0.2182 0.0027 0.0002 0.0025 0.0031 iO'OOIB 0.000036 Cod liver oil h.5 MOoE Total 1559.5 55.52 1518.98 1.0989 1.6512 1.0808' 0.2680 3.6013 1.2226 0.6627 0.018095 327.5 827.5 * Table represents quantities given to D. Sabject B amounts given. Percentage composition calculated from the following sources: Produced by eating Frunes and Cranberries J.B.C. 57. pages 815'818. 1925 R089: hazy Sc. iandbook for Dietitics, 5rd Edition, maAlmMillan 19290 Storms, Lillian B., Analytical Data Included in pamphlet "fiaby's Vegetables" - Gerber Products Company, Fremont, hfichigan. ‘fialler, Dorothy 8., Nutritive Value of Foods. weighed approxinately 0.1 more than D and therefore was provided with 1.1 times the George wahr, Ann Arbor, Midhigan 1952. Blatherwick,‘N.R., Studies of Urinary'Acidity. II.The Increased Acidity COMPOSITION OF THE TABLE III ZIUEIPQOTEIH DIET* * Same as medium.protein diet. FOOd.1m.. eight Protein Calories Sodium PChlorine Calcium Eagnesium. Potasium Phosphorous sulphur Iron AcigeéldueBase ‘—" 7777 gms. 'gms. ' gms. gms. ngo gms. gms. gms. gms. gms. cc n/10 cc n/10 hole :ilk 825 18.03 293.3 0.2133 0.8505 0.5100 .0510 0.6078 0.3953 0.1885_ 0.001020 76.5 Skim . 11 825 18.85 157.2 0.2210 0.8675 0.5185 0.0510 0.6333 0.8080 0.1888 0.001063 76.5 382 90 12.06 133.2 0.1287 0.0958 0.0603 0.0099 0.1260 0.1620 0.1755 0.002700 99.9 Ra. beef 90 19.17 180.8 0.0810 0.0729 0.0108 00.0225 0.3289 0.2070 0.2196 0.002160 103.5 Bhole wheat bread 60 5.82 187.6 0.2368 0.3682 0.0300 0.0300 0.1288 0.1050 0.0720 0.000960 83.8 Uncooked farina 18 2.00 05.2 0.0117 0.0157 0.0081 0.0085 0.0216 0.0761 0.0279 0.000900 17.3 Cooked pct-to 50 1.10 81.5 0.0105 0.0190 0.0070 0.0180 0.2185 0.0290 0.0150 0.000650 30.0 Strained tomatoes 100 1.92 82.1 0.0150 0.0550 0.0200 0.0100 0.3100 0.0371 0.0180 0.001900 56.0 " carrots 70 0.81 15.8 0.0707 0.0252 0.0206 0.0187 0.2009 0.0123 0.0158 0.000770 75.6 " prunes 90 0.89 62.5 0.0621 0.0153 0.0219 0.0895 0.9270 0.0353 0.0333 0.003800 156.0 " applesauce 90 0.18 181.3 0.0099 0.0085 0.0063 0.»072 0.1183 0o0108 0-005h 0-000270 80.5 Lettuce 18 0.17 2.7 0.0038 0.0108 0.0060 0.0028 0.0875 0.0059' 0.0020 0.000098 10.8. Orange juice 200 86.0 0.0160 0.0060 0.0580 0.0220 0.3680 0.0320 0.0180 0.000800 90 6’ Sugar 10 80.0 Butter 20 0.20 153.8 0.1576 0.2828 0.0030 0.0002 0.0028 0.0038 0.0020 0.000080 COd liver oil 0.5 00'5 Total ‘1756.5 72.10 1"63.28 1.2812 1.8820 1.289§__ 0.2889 8.0198 ‘1.5192 0.8938 0.016731 821.5 855.5 in the quantities of the other foods were very slight. These tables also indicate that the mineral content and the acid/base residue of the two diets were relatively constant. On both diets the children drank a measured amount of distilled water daily. The investigators made careful plans to eliminate as many errors as possible in the feeding of the diets. They pur— chased in advance canned and dried foods sufficient to last for the entire eXperiment. They obtained perishable foods in quan— tities large enough to last for a three day period. The helpers removed the fat and grisle from the meat and ground the lean portion, beat all eggs thoroughly, cooked and mashed the potatoes and pureed the vegetables and fruit. They then mixed together thoroughly the quantity necessary for a three day period until it formed a homogenous mass. Next they weighed all the neces- sary portions for a three day period into individual utensils. The children consumed the portions directly from these utensils in which they were first cooked. In order to be sure of quan- titative consumption the helper supervising the meal wiped each dish out with a small portion of the days allotment of bread, which the children ate and then rinsed the dishes with some of the measured distilled water. This was added to some other food . which the child had not yet eaten. Two identical portions of the homogenous mixture were weighed at the same time for analysis. They were placed in enamel bowls, partly dried over a steam bath and then placed in a constant temperature oven at 60 degrees Centigrade until they reached a constant weight. They were then ground several times and put through a fine mesh sieve. If some of the material was too hard to pass through the sieve, this was mortared, sif- ted and added to the other portion. From 15 to 20 grams samples of the food were weighed in duplicate. These samples were ashed in platinum dishes, at a dull red heat, dissolved in 5 - 10% H Cl and made up to a volume of 100 cc for later analysis. Specimens Care was taken to collect the excreta as quantitatively as possible. The children were trained to follow a definite schedule for collection and thereby prevent the loss of urine. If there was an unavoidable accident the Specimen* for the en- tire dey was discarded and the results for the other two days of the period were averaged. Decomposition was limited by keeping the samples in an ice box at all times. After the 24 hour Specimens had been measured and the specific gravity taken they were made up to a definite volume with distilled water. Duplicate and triplicate determinations of sodium were made on daiLy Specimens of the fresh urine. In an attempt to collect daily excretion of feces quantitatively, carmine and charcoal were fed on alternate days as markers. Since the amount excreted daily was small, it was difficult to separate the samples accurately. After collection, the fecal specimens were dried at a low temperature, mortated and sieved in the same manner as the food. They were ashed at a temperature below red heat, dissolved in H Cl and made up to a volume of 100 cc. . —9— CHEMICAL METHODS Review of Literature There are five general methods for the quantitative determination of sodium, the platinc-chloride, the pyroantimonate, the perchlorate, the caesium bismuth.nitrite and uranyl acetate methods. (5, 4, 6, 7, 8, 9, 10, ll, 15, 15, 16, 19, 20, 25a, 25b, 26, 27, 28, 29, 52, 55, 55, 59), Various workers have adapted these methods to either volumetric, colorimetric or gravimetric procedures. A brief discussion of the methods follows. In the platinic-chloride method the sodium and potas- sium are weighed together as sulphates and the potassium is determined as a chloro-platinate (52). Thus the sodium is subject to the greater error because it is determined by difference. In the pyroantimonate method, sodium is precipitated with potassium pyroantimonate solution and titrated with sodium thiosulphate using potassium iodide as an indicator (52). Peters and Van Slyke state that this "method offers the only micro—titration method for sodium." They say further that, 1'it is capable of giving good results, but is susceptible to error from slight changes in tech- nique, and the potassium pyroantimonate used as a reagent, obtained from dealers, has often been unsatisfactory.” (52). The perch— lorate method has not been adapted for use with biological mater- ials (39). According to McCance and Shipp the precipitation of sodium as caesium bismuth nitrate presents many technical difficul- ties, the chief of which is that the precipitate must be kept in a cold room twenty-four hours (28). The preceeding methods were .10... not used to determine sodium in this study, either because pre- vious investigators reported that they presented technical difficulties or they had not been adapted to use with biological material. A number of workers have reported that the uranyl acetate method was satisfactory for use with biological material. The basis of this method is that sodium forms quantitatively a triple salt with a saturated solution of uranium and either magnesium or mine acetate. This triple salt is very slightly soluable in 95% alcohol, ether or glacial acetic acid. The high molecular weight of the salt makes it possible to determine very small amounts of sodium. The precipitate may be weighed or adapted to colorimetric or volumetric analysis. (5, 4, 6, 7, 8, 9, 10, 15, 15, 19, 25a, 25b, 26, 28, 55). The history of the method indicates that the earlier workers used magnesium acetate to form the triple salt while the later investigators used zinc acetate. In 1886, the earliest record of the uranyl acetate method, Streng used the magnesium salt to precipitate sodium (55). Although other authors as Blanchetiere, have used a magnesium reagent, Barber and Kolthoff say that his method showed errors from -6.0 to +5.0 percent, and "Crepaz reports the method too inaccurate for the gravimetric determination of sodium? (la, 5). Caley and his associates used magnesium reagent for the determination of sodium in inorganic material (7, 9, 10, 11, 19). They applied their method to gravimetric and colorimetric procedures and found it satisfactory -11... if the amounts of sodium determined did not fall below 0.2 milligrams (7). There has been considerable diSpute regarding the composition of the triple salt. Streng originally assigned the formula (U 02)?) Mg Na (CH5 coo)9 . 9 H20, which Blenchetiere later confirmed. Milholic, however, believed that it contained only six molecules of water. More recently Barber and Kolthoff have studied the composition of the salt. They precipitated the sodium with zinc rather than magnesium and obtained better results (la). They agreed with Hilholic and gave the formula (002),5 Zn Na (CH5£OO)9. 6 H20 to their product. The ratio of the weight of sodium to that of the triple salt is, therefore, 0.01495:1 (55). Barber and Kolthoff also studied extensively the in- fluence of various ions on the determination of sodium by this method. They found that ammonium, calcium, barium and magnesium do not interfere, that caesium and rubidium do not influence the results if present in Guantities as small as 0.1 grams or less, that lithium, strontium and organic acids interfere, that po— tassium introduced an error if present in as large amounts as 50 milligrams per 1 cc, that phOSphates and arsenates interfere and, therefore, must be removed by a magnesia mixture. Butler and Tuthill modified the method of Barber and Kolthoff and applied it to the quantitative determination of sodium in urine. Their results were satisfactory with samples -12.. containing as little as 1.5 milligrams of sodium (6). Salit adapted the above method to a colorimetric procedure for use in determining sodium in biological material. He obtained excellent results which showed an error of not more than 2 - 5% with samples containing as low as 0.05 milligrams of sodium (55). Chemical Method Used Both the Butler and Tuthill and Salit modifications were tried in this laboratory. Preliminary checks were made on known solutions of sodium salts, on urine and on samples of the same Specimen of urine plus a known quantity of chemically pure sodium salt. In general, the Salit procedure was as follows: 2cc of the sample was placed in a centrifuge tube. The same quantity of a standard sodium chloride solution, containing approximately the same amount of sodium was placed in another centrifuge tube. To these was added 6 cc of the uranyl zinc acetate reagent. Suc- cessive 0.5 cc portions of absolute alcohol were added to each tube and the contents stirred. When precipitation was complete the tubes were centrifuged for 10 minutes. The supernatant fluid was decanted and the tube allowed to drain on filter paper. The precipitate was washed with glacial acetic acid saturated with uranyl zinc acetate which had been freshly filtered. The precipitate was transferred to a 50 cc volumetric flask hy rins- ing with distilled water and was then made up to volume. An aliquot sample was removed (the size of the portion depending -15- upon the amount of sodium present) and 0.5 cc of a 20% po— tassium ferroqyanide solution was added. The samples were then read in the calorimeter (55). To determine the accuraqy of this procedure the sodium was recovered on thirty—four samples of a known sodium chloride solution and on twenty-five samples of a standard sodium sulphate solution. As shown in Table IV, there was a wide variation in the per cent recovery, the averages being 97.65% and 91.16% for the sodium chloride and the sodium sulphate solutions. The unsatisfactory results obtained with the Salit modification may be explained in part by the fact that the colorimetric procedure is subject to var- iations due to the difficulty some workers have in matching color values. Also the work was done in extremely hot weather when. the laboratory temperature frequently exceeded 100 degrees Fahrenheit and elevations of temperature effect the soluability of the uranium salt. Table IV indicates that more consistent results were obtained with the Butler and Tuthill gravimetric method. At first an attempt was made to dry the precipitated sodium uranium zinc acetate to constant weight. This gave as unsatisfactory results as the Salit method. Since Butler and Tuthill had stated that it was sufficient to dry the precipitate and the filter con- taining it in as dissicator over calcium chloride for % hour before weighing, this procedure was followed and the recovery of known salt was considerably more constant. Fourteen determinations were PERCENT -14.. TABLE IV RECOVERY ON KNOWN SOLUTIONS OF A SODIUM SALT USING TWO METHODS a 0d Salt t Na 01 (Colorimetric) N32 8% tler and Na 01* thill Na 01 (Gravimetric) Na£2 80: Ni 8%, Na 01 Na '01 L Na 01 Concentration cc «NHNNNIO Salt Sglutiggfififlrigg CO HI—‘HOOOO Determin no. 25 14 14 Rangeflof ,rgcgvgrz per cent 80.71-125.00 75.76- 98.55 94.06-100.95 99.05-102.51 94.12- 99.97 97.89-100.55 96.10-100.15 98.68-100.10 98.85-100.16 Average r.£§£9!£l! per cent 97.65 91.16 98.22 100.21 97.25 99.19 98.49 99.58 99.52 * Dried in oven ** Same standard to constant weight. solution of Na 01 and Na So4 used for both methods. 2 -15.. made using the latter method on 2 cc samples of stcidord sodium Chloride solution and eleven on 2 cc portions of a known sodium sulphite solution. The percentage recovery of sodium averrged 100.21% and 99.19% respectively. To further check the accuracy of the method five determinations each were made on dilutions of 1 cc of urine plus 1, 2, and 5 cc of the known sodium chloride solution. The average percentage recovery was in order 98.49%, 99.58% and 99.52%. These results were deemed sufficiently accur— ate to warrant the use of the method as outlined below. Certain preliminary steps were necessary with each of _the biological products before the general method of precipitation of the triple salt w~s put into effect. For urine a 6 cc sample was pipetted into a test tube. To this was added approximately 0.2 grams of calcium hydroxide together with 1 drop of phenol- thalein. (The calcium hydroxide was used to precipitate the phOSphates. The urine had previously been tested and found to be free of protein, therefore, it was not necessary to remove it.) After standing 50 minutes the solution was filtered and the filtrate used for the determination of sodium. In the case of food a sample of the dried material weighing between l5 and 20 grams was dry ashed and the ash made up to a volume of 100 cc. An aliquot portion of this was removed for analysis, the size of which depended upon the original weight of the ashed sample. Exactly six, ten or twenty cc portions of the ash solution was measured into a test tube and approximately 0.2 grams of calcium hydroxide was added to precipitate the phosphate. -15- After 30 minutes this was filtered and the filtrate evaporated to a volume of approximately 2 cc. Some slight modifications were necessary in the method for the determination of sodium in the feces. The quantity of sodium was so small that it was necessary to add a known amount of standard sodium chloride solution to each sample. Because of a limited amount of material potassium and sodium were determined on the same sample. The potassium and sodium were precipitated as sulphates and the precipitate was transferred to a 100 cc beaker by successive washings with distilled water. This was then evaporated to dryness to remove the H 01 present. The dried material was dissolved in distil- led water and approximately 0.2 grams of powdered calcium hydroxide added. After standing 50 minutes it was filtered and the filtrate evaporated to approximately 2 cc. After the prelimin- ary steps had been taken the precipitation of the sodium as a triple Salt was essentially the same. A solid rubber stOpper was fitted from below into the bottom of a 50 cc porous glass filter (Jena Glass filter size 2, capacity 50 milliliter, por— osity l G 4) that had been dried and accurately weighed. 20 cc of the uranyl zinc acetate reagent (freshly filtered) was placed in the glass filter and the sample added. This solution was stirred with a small glass rod until a precipitate appeared and several minutes thereafter. The filter was then covered with a watch glass and allowed to stand at room temperature for 1 hour. The rubber stepper was removed and the filter placed in a suction flask and suction applied. The precipitate was -17- first washed vith 95% alcohol thich had been saturated vith the triple salt and then with ether and finally dried in a dessica- tor over night. The dried precipitate was weighed and the amount of sodium in the sample determined ty'multjplying its weight by the factor 0.01495. Flank corrections were made on all samples. In the case of feces the sodium in the carmine and charcoal used as markers was deterrined and subtracted from the weight of the final precipitate. Checks within 1 2% were obtained with food and urine using samples that contained as low as 0.5 milligrams of sodium. This has considered suf— ficiently accurate for our purpose. Although the results on feces were less satisfactory than those on the other materials, the results were considered accurate enough for the small Guan- tities of sodium excreted by way of the intestinal tract. No attempt was made to determine the sodium lost in perSpiration or tears. Previous workers differ as to whether the loss is sufficiently great to consider. Bominger and Meyer using infants fed on cow's milk concluded that the amount of sodium lost through the skin did not materially effect is re- tention. Swanson and Iob, however, stated "It is amperent from our data that no metabolic experiment involving retention of minerals can be correctly evaluated unless loss through the skin is determined ” (40). To have made this determination on the present eXperiment would have presented great difficultie in collection of the material. -13- RESULTS AND DISCUSSION Sodium Metabolism - Da 1y - Medium and High Protein Qigtg Table V presents the daily sodium balances obtained on the two children used in this study, and Table VI data on a per kilogram basis.* They indicate that the daily amounts of sodium injested for each day during a three day period were identical due to the method of preparing the food. The amounts from period to period, however, varied considerably since a small quantity of unweighed sodium chloride was added to the food during preparation. Nevertheless, this amount was the same in the analyzed sample as in the food eaten by the child- ren. As a result the actual number of grams received by the ' children daily were slightly higher than was anticipated in the calculated diets. In addition to the intake, Table v shows the daily fecal and urinary output, the retention and absorp- tion of sodium for the two subjects on the medium and high protein diets. The tendencies evidenced by the two subjects were remarkably consistent and are, therefore, discussed together. Although the sodium in the food varied only by three day periods, there were wide variations in the daily fecal and urinary excretion. The fecal sodium was low and there were probably errors incurred by daily collection for the samples * Figures for the first six days of the experiment obtained from unpublished data determined by Mrs. Merle M. Bray, Division of Home Economics, Michigan State College. TA BL E V Dill LY 5:3 QDI UM BELLMT CBS ‘ g m 1 Ah 8 01:70-13: 0 n ' ' jiet entio‘n” .2... L Proportion Proportion Subject Diet Date Intake Feces Urine Total . Total 9—«9‘ into .ECe -- .. ”110ml .EIEMjfi’i’Liafi—g? ‘ ”Elsi“ gms . gms . .. 29:18 . 5; ms. oer c eat gins . 718 r cent D Med. 2/16 1.558 0.055 1.220 1.255 1.525 97.9 0-135 6.72 Prot. 2/17 1.558 0.015 1.698 1.711- 1.525 99.2 -0.155 2/18 1.558 0.018 1.625 1.661 1.520 98.6 -0.105 2/19 1.069 0.009 1.195 1.202 1.060 99.2 —0.155 2/20 1.069 0.051 0.802 0.855 1.058 97.1 0.256 22.08 2/21 1.069 0.056 0.892 0.928 1.015 92.6 0.121 11.52 2/22 1.125 0.000 1.025 1.025 1.125 100.0 0.100 8.75 2/25 1.125 0.002 0.952 0.956 1.125 99.8 0.209 18.25 2/22 1.125 0.000 1.092 1.092 1.125 100.0 0.055 2.95 2/25 1.065 p 0.002 0.955 0.955 1.061 99.8 0.128 12.02 2/26 1.065 0.000 0.922 0.922 1.065 100.0 0.121 11.58 2/2 1.065 0.012 1.002 1.018 1.029 98.7 0.025 2.25 2/28 1.159 0.015 0.952 0.927 1.122 98.7 0.212 18.29 2/29 1.159 0.008 1.026 1.052 1.151 99.5 0.125 10.79 5/1 1.159 0.016 1.080 1.096 1.125 98.6 0.065 5.22 5/2 1.022 0.002 0.997 ‘ 0.999 1.022 99.8 0.025 2.22 5/5 1.022 0.000 0.862 0.862 1.022 100.0 0.162 15.82 5/2 1.022 0.002 0.905 0.090 1.020 99.6 0.115 11.25 5/5 1.028 0.000 1.155 1.155 1.028 100.0 —0.105 5/6 1.028 0.002 0.979 0.985 1.022 99.6 0.025 2.58 5/7 1.028 0.021 0.952 0.955 1.007 98.0 0.075 7.10 High 5/8 1.298 0.002 1.256 1.258 1.296 99.9 0.020 2.67 Prot. 5/9 1.298 0.000 1.287 1.287 1.298 100.0 0.211 12.09 5/10 1.498 0.005 1.272 1.27, 1.295 99.8 0.221 12.75 5/11 1.102 0.000 1.121 1.121 1.102 100.0 e-0.017 5/12 1.102 0.002 0.895 0.897 1.102 99.8 0.207 18.75 5/15 1.102 0.000 1.177 1.177 1.102 100.0 —0.075 5/12 1.525 0.000 1.256 1.256 , 1.525 100.0 0.087 6.26 5/15 1.525 0.001 1.201 .202 1.522 99.9 0.121 10.50 5/16 1.525 0.000 1.212 1.212 1.525 100.0 0.129 9.61 5/17 1.092 0.052 1.091 1.125 1.060 96.9 +0.051 5/18 1.092 0.00 1.051 1.051 1.092 100.0 0.025 5.95 5/19 1.092 0.005 1.050 1.055 1.089 99.5 0.059 5.56 5/20 1.190 0.000 1.129 1.129 1.190 100.0 0.021 5.25 5/21 .1.190 0.009 0.972 0.981 1.181 99.2 0.209 17.56 5/22 ’ 1.190 0.000 0.916 0.916 1.190 100.0 0.272 25.05 B med. 2/16 .1.712 0.026 1.562 1.588 1.688 98.5 0.726 19.02 Prot. 2/17 1.712 70.025 1.278 1.505 . 1.689 98.5 0.211 .12.51 2/18 1.712 0.059, 1.277 1.516 1;675 97.7 0.198 11.55 2/19 1.176 0.072 1.510 1.582 1.102 95.9 -0.206 2/20 1.176 0.010 1.128 1.158 1.166 . 99.1 0.018 1.55 2/21 1.176 0.050 1.066 1.096 1.126 97.2 0.080 6.80 2/22 1.260 0.005 1.025 1.028 1.255 99.6 0.252 18.21 2/25 1.260 0.020 1.157 1.177 1.220 98.2 0.085 6.59 2/22 1.260 0.055 1.151 1.166 1.225 97.2 0.092 7.26 2/25 1.169 0.002 0.980 0.982 1.165 99.7 0.185 15.85 2/26 ,1.169 0.012 0.929 0.965 1.155 98.8 0.206 17.62 2/27 . '1.169 0.011 1.018 1.029 1.158 99.1 0.120 11.98 2/28 1.275 0.009 1.298 1.507 1.266 .5 -0.052 2/29 1.275 0.012 1.257 1.229 1.265 99.1 0.026 2.02 5/1 1.275 0.008 0.912 0.922 1.267 99.2 0,555 27.69 5/2 1.126 . 0.015 1.197 1.210 1.115 98.3 -0,032 5/5 1.126 0.000 1.010 1.010 1.126 100.a 0.116 10.50 5/2 1.126 0.012 0.985 0.995 1.112 98.; “0.151 11.65 5/5 1.151 0.008 1.151 1.159 1.125 99.; -0,008 5/6 1.151 0.027 1.075 1.102 1.102 97.6 0,029 2.25 5/7 1.151 0.022 1.112 1.158 1.087 96.1 -0.027 ' High 5/8 1.628 0.012 1.261 1.275 1.652 99.2 0.575 22.65 Prot. 5/9 1.628 0.001 1.289 1.290 1.627 99.9 0,158 9.59 5/10 1.628 0.015 1.505 1.516 1.655 99.2 0.152 8.01 5/11 1.215 0.010 1.500 1.510 1.205 99.2 -0.095 5/12 1.215 0.052 1.126 1.158 1.185 97.2 0.057 2.69 5/15 1.215 0.002 1.526 1.550 1.211 99.7 -0.115 5/12 1.278 0.002 1.112 1.118 1.272 99.7 0.560 22.56 5/15 1.278 0.025 1.555 1.560 1.255 98.3 0,118 7.98 5/16 1.278 0.002 1.609 1.611 1.276 99.9 -0.133 5/17 1.205 0.028 1.017 1.025 1.175 97.7 0,158 13.15 5/18 1.205 0.025 1.528 1.575 1.178 97.9 -0.170 ' 5/19 .205 0.001 1.162 1.165 1.202 99.9 0,020 3.33 5/20 1.509 0.000 0.962 0.962 1.509 100.0 0.525 26.55 5/21 1.509 0.008 0.915 0.925 1.501 99.2 0,586 ggobg 5/22 1.509 0.000 1.102 1.102 1.509 100.0 0,207 15.81 -61— Diet M6 (l o Prot. High PTOt. Me d . Protc High Prot- 1 T111311?) VI 3121‘ 11’ SOLE U}: 3 10101-. _ 15-10.11 01 11:, ‘Y -':;:017_T Output Date Teight Intake Feces Urine Total 2bsorption Retention kg. $08. Ems. gms. 3mg? gms. Ems“ 2/16 17.25 0.6895 0.0019 0.0812 0.0855 0.0872 0.0060 2/17 17.25 0.0895 0.0007 0.0975 0.0980 0.0886 —0.0087 2/18 17.25 0.0895 0.0010 0.0922 0.0952 0-0885 -O-OQ59 2/19 17.59 0.0615 0.0005 0.0686 0.0691 0.0010 -0.0076 2/20 17.59 0.0615 0.0018 0.0261 0.0279 0.0597 0.0156 2/21 17.59 0.0615 0.0052 0.0515 0.0525 0.0585 0.0070 2/22 17.21 0.0658 0.0000 0.0600 0.0600 0.0658 0.0058 2/25 17.21 0.0658 0.0001 0.0556 0.0557 0.0657 0.0121 2/22 17.21 0.0658 0.0000 0.0627 0.0627 0.0658 0.0051 2/25 17.50 0.0607 0.0001 0.0555 0.0552 0.0606 0.0075 2/26 17.50 0.0607 0.0000 0.0558 0.0558 0.0 07 0.0069 2/27 17.5) 0.0607 0.0008 0.0572 0.0582 0.0599 0.0025 2/28 17.55 0.0660 0.0009 0.0551 0.0520 0.0651 0.0120 2/29 17.55 0.0660 0.0005 0.0585 0.0590 0.0655 0.0070 5/1 17.55 0.0660 0.0009 0.0615 0.0622 0.0651 0.0059 5/2 17.21 0.0588 0.0001 0.0575 0.0572 0.0587 0.0012 5/5 17.21 0.0588 0.0000 0.0295 0.0295 0.0095 0.0588 5/2 17.21 0.0568 0.0002 0.0520 0.0522 0.0586 0.0066 5/5 17.25 0.0589 0.0000 0.0629 0.0629 0.0589 -0.0060 5/6 17.25 0.0589 0.0002 0.0561 0.0565 0.0507 0.0026 5/7 17.25 0.0589 0.0012 0.0555 0.0527 0.0577 0.0(22 5/8 17.25 0.0858 0.0001 0.0852 0.0855 0.085: 0.0025 5/9 7.25 0.0856 0.0000 0.0758 0.0758 0. 858 0.0120 5/10 17.25 0.0858 .0002 0.0750 0. 752 0.0126 0.0856 5/11 17.25 0.0655 0.0000 0.0622 0.0622 0.0655 -0.0009 5/12 17.25 0.0655 0.0001 0.0515 0.0512 0.0652 0.0119 5/15 17.25 0.0655 0.0000 0.0872 0.0672 0.0655 -0.0021 5/12 17.21 0.0771 0.0000 0.0721 0.0721 0.0771 0.0050 5/15 17.21 0.0771 0.0001 0.0690 0.0691 0.0770 0.00Ct 5/16 17.21 0.0771 0.0000 0.0697 0.0697 0.0771 0.00"; 5/17 17.50 0.0625 0.0019 0.0625 0.0622 0.0606 -0.0017 5/18 17.50 0.0625 0.0000 0.0601 0.0601 0.0625 0.00:2 5/19 17.50 0.0625 0.0005 0.0600 0.0605 0.0622 0.0022 5/20 17.50 0.0680 0.0000 0.0657 0.0657 0.0680 0.0025 5 21 17.50 0.0680 0.0005 0.0555 0.0560 0.0675 0.0120 5/22 17.50 0.0630 0.0000 0.0525 0.0525 0. 680 0.0157 2/16 19.00 0.0902 0.0012 0.0717 0.0751 0.0888 0.0171 2/17 19.00 0.0902 0.0015 0.0778 0.0791 0.0889 0.0111 2/18 19.00 0.0902 0.0021 0.0777 0.0798 0.0881 0.0102 2/19 19.00 0.0619 0.0058 0.0689 0.0727 0.0581 —0.0108 2/20 19.00 0.0619 0.0005 0.0602 0.0609 0.0612 0.0010 2/21 19.00. 0.0619 0.0016 0.0561 0.0577 0.0605 0.0022 2/22 18.98 0.0662 0.0005 0.0559 0.0522 0.0661 0.0122 2/25 18.98 0.0662 0.0011 0.0610 0.0621 0.0655 0.0025 2/22 18.98 0.0662 0.0018 0.0596 0.0612 0.0626 0.0050 2/25 18.98 0.0616 0.0002 0.0516 0.0518 0.0612 0.0098 2/26 18.98 0.0616 0.0007 0.0500 0.0507 0.0609 0.0109 2/27 18.98 0.0616 0.0006 0.0556 0.0522 0.0610 0.0072 2/28 19.00 0.0671 0.0005 0.0685 0.0688 0.0666 -0.0017 2/29 19.00 0.0671 0.0006 0.0651 - 0.0657 0.0665 0.0012 5/1 19.00 0.0671 0.0002' 0.0281 0.0285 0.0667 0.0186 5/2 18.98 0.0595 0.0007- 0.0651 0.0658 0.058 —0.0025 5/5 18.98 0.0595 0.0000 0.0552 0.0552 0.0595 0.0061 5/2 18.98 0.0595 0.0006 0.0518 0.0522 0.0587 0.0069 3/5 19.05 0.0592 0.0002 0.0592 0.0598 0.0590 —0.0002_ 3/'6 { 19.05 0.0592 0.0012 0.0562 0.0578 0.0580 0.0016 5/7 ‘ 19.05 0.0592 0.0025 0.0585 0.0608 0.0571 0.0012 5/3 18.98 0.0868 0.0007 0.0662 0.0671 0.0861 0.0197 5/9 18.98 0.0868 0.0001 0.0785 0.0786 0.0867 0.0082 5/10 18.98 0.0868 0.0007 0.0792 0,0799 0.0861 0.0069 5/11 18.98 0.0920 0.0005 0.0685 0.0690 0.0655 -0.0050 5/12 18.98 0.0920 0.0017 0.0595 0.0619 0.0625 0.0050 5/15 18.98 0.0020 0.0002 0.0699 0.0701 0.0658 -0.0061 5/12 19.05 0.0776 0.0002 0.0585 0.0587 0.0772 0.0189 5/15 19°05 0-0776 0-0015 0.0701 0.0712 0.0765 0.0062 5/16 19-05 0.0776 0.0001 0.0825 0.0826 0.0775 -0.0070 §é%g 19.09 0.0650 0.0015 0.0555 0.0528 0.0615 0.0082 19.09 0.0030 0.9015 0.0706 0.0719 0.0617 -0.0089 5/19 19.09 0-0950 0.0001 0.0609 0.0610 0.0629 0.0020 5/20 19.09 0.0686 0.0000 0.0505 0.0505 0.068 0.0181 5/21 19.09 0.0686 0.0002 0.02 9 0.0285 0.0682 0.0205 5/22 19.09 0.0686 0.0000 0.0577 0.0577 0.0686 0.0109 7... -O', . . ' I . ‘ I . o m o I I a a o u 6 v o o - o o n o o O 0 O I O C -21- were small and it was difficult to separate them sharply. A small amount of the injested sodium was excreted in the feces and the major portion was eliminated in the urine. Urinary sodium ranged from 0.802 grams to 1.698 grams daily for the two subjects. There was a small amount of fecal sodium and a high degree of absorption. The per cent of injested sodium absorbed daily by the two subjects during the entire experi- ment ranged from 93.9% to 100.0%. The smallest range in per cent of intake was shown on the high protein diet as indicated in Table V. In contrast to feces and urine the daily absorp- tion of sodium closely paralled the intake. Inasmuch as retention represents the difference between absorption and urinary excretion it is obvious that the daily retention var- ied widely. Table v shows a number of negative balances as well as some balances when there was a relatively high reten- tion of sodium. In sixteen cases out of twenty—four there was a slight drop in the daily amount of sodium retained following a change in the sodium intake. This drop occurred whether the dietary sodium had been increased or decreased. This would seem to indicate that there was a lag in the elimination of sodium from day to day and that the subjects never were in sodium equilibrium. As a result of the preceeding observations statistical determinations were made in order to ascertain the relationship between intake and excretion, absorption and retention. Table VII shows a definite correlation between daily intake and urine, total excretion and absorption of sodium for the two subjects on -22- 9.2 22628622 .26-. .4 93. ME“ find flaw... ENEHAH H.“ HH> ... 0:H. NoH.o NHm.ouemo.on NH mmo.o Hmo.o 86H.o NNN.H 666.H-moH.H NH 0H6.o 666.0 mmH.o HoN.H 66:.H1Nmm.o NH 80.6 :qo.o mmH.o 66H.H 6.“.H-Nmo.o NH :oo.o- moo.o 6Ho.o 6Ho.o emo. o-mao.o NH mom.H 866.6 88H.o mom.H qu.H 6 H.H N mmo.o- mHo.o 866.0 Noo.o meH.o-omo.o NH mmm.o Nmo.o 06H.o HnH.H emm.HuNNo.H NH mmm.o Ono.o mmH.o ecH.H 660.Hnm 8.0 NH 668.6 666.6 mmH.o mao.H eem.H-HNm.o NH JNo.o moo.o oHo.o 606.0 Nmo.o-Hoo.o NH N66. 06H.o omH.H Nam.HuzNo.H NH eOHnem qu.o 026.6 mmH.o 66H.o 66m.ouooN.ou 6m wmm.o Nmo.o mmH.o NNN.H mm0.Haeoo.H a 0m N66.o Hmo.o 66H.o H6N.H on.H HuNN .o .7 366.0 Hmo.o mNH.o ncH.H mao.Hn:Hm.o 6m Noo.on moo.o «H6.o 6H6.o Neo.o-Hoo.o pm . Nmo.o mmH.o mom.H qu.H-6NH.H 6m NNo.o- mHo.o NH6.o Neo.o mmN.oummH.ou 0m 66.6 mNo.o maH.o HmH.H H46.H-866.H mm mmm.o mmo.o NON.o 86H.H HHe.H-6mm.o 6m Nmm.o mmo.o eoN.o NNO.H 666.H-N>>. mm mHo.o Noo.o mHo.o moo.o M6o.o-Hoo. o 6m mNo.o 66H.o 00H.H N.6.H-:No. H m KHHHS e mflHU caepGH ape; hopnm aoapsflpom mega oweam monEsm nOHpeHonnoo eneecepm oneeeepm 6H26026H6< No .om we 80682268 DHQOm no BO 9 COHvsopom Gowpma0m9< QOHponoHo H8905 mafia: woomh endan scannepmm Soappnownd dowpmaoxo prou omen: wmomh oxepmH QOszmpmm 20Hgan009.« 20H+ onox. H8208 emanp mooom oadpmH uoHpaopom nowpm206nq CoHponoMo Hapom omwnb mooeb mhc PCH QNH. .200 6 poehhzm -25- the entire eXperiment. It shows no correlation between in- take and total excretion or retention. It indicates that in all cases there was a slightly higher correlation when the comparisons were made on a period basis. 0n the former basis the range in values was smaller but otherwise the relation- ships were the same. Because the diet was constant for a three day period and it may eliminate some of the errors in fecal output of sodium, the interpretation of results which follow will be expressed in terms of the average amount of sodium for a three day period. Sggium Metabglism Q: Eeriggg - M ium Protein Diet The sodium intake on the medium protein diet varied widely from period to period on the basis of both the total grams of sodium and the grams per kilogram of body weight as shown in TablesVIII and II. The range in sodium intake per kilogram of body weight for subjects D and B was from 0.0588 to 0.0895 and 0.0595 to 0.0902 grams per period. This provided for a wide per cent variation from the average period intake ranging from +55.5% to -lO.9%. Although the number of grams of sodium per kilogram of body weight varied per day and per period the average intake for the two subjects on the medium protein diet was similar. Subject D averaged 0.0658 grams and B, 0.0666 grams of sodium per kilogram of body weight per period. Excretion of sodium in the feces was small. Although not as great as on'a daily basis, the period excretion of sodium in the feces varied considerably. The sodium eliminated in this ~24- 66.6N NH6.0 6.66 606.H 666.0 666.0 600.0 606.H NH 66.0 606.0 6.66 66H.H 66H.H 66H.H 6H0.0 60N.H HH 66.6 6HH.0- 6.66 66:.H 666.H 666.H 0H0.0 66:.H 0H H60.0- 6.66 00N.H 66N.H H6N.H 6H0.0 6HN.H 6 H:.6H HNN.0 6.66 666.H 6N4.H 6H:.H 660.0 666.H 6 N00.0- 6.66 60H.H 66H.H 60H.H 6N0.0 H6H.H a 66.: 660.0 6.66 6HH.H H60.H 660.H 600.0 6NH.H 6 No.6 6HH.0 N.66 66N.H 06H.H 06H.H 0H0.0 66N.H 6 6H.6H 66H.0 H.66 66H.H N66.0 N66.0 0H0.0 66H.H 6 66.0H 66H.0 6.66 06N.H JNH.H 60H.H 0N0.0 06N.H 6 660.0- 6.66 66H.H NHN.H 66H.H 660.0 66H.H N 6N.:H 66N.0 N.66 :66.H 666.H 666.H 060.0 :Hs.H H H6.HH 66H.0 6.66 66H.H 6H0.H NH0.H 600.0 06H.H NH 66.H 6H0.0 6.6m H60.H 660.H 460.H 6H0.0 :60.H HH 66.6 6HH.0 0.00H 6:6.H 6NN.H JNN.H 000.0 646.H 0H 66.6 660.0 6.66 60H.H 660.H :60.H H00.0 40H.H 6 6:.0H 66H.0 6.66 666.H H66.H 666.H N00.0 666.H 6 66.0 600.0 N.66 0N0.H 6N0.H 6H0.H 600.0 6N0.H s 66.6 HOH.0 6.6m NN0.H 6N6.0 HN6.0 N00.0 6N0.H 6 6:.HH 66H.0 6.66 64H.H 6N0.H 6H0.H 6H0.0 66H.H 6 NN.6 660.0 6.66 660.H 666.0 066.0 600.0 660.H : 6:.0H 0NH.0 6.66 46H.H 6N0.H 4N0.H H00.0 6JH.H 6 No.6 6 60.0 0.66 6604 666.0 N666 N60.0 6604 N 060.0- 6.66 666.H 606.H 666.H HN0.0 666.H H 6.50 Mom 5an “Eco .Hom .wsw .686 .656 3an Jam oaspsH 66 H6666 .\ gaspsH so H6666 H6666 66H»: .6666 oasan soHnmm noHtomoAm noHnTHonHoan #9350 666666666 lawmmfimmmmwll2 QOHmmE mam mach/Eda EDHQOm A6509 ovonm 66Hm . tam .66a .686 amHm . 6.86 .662 pon 6666666 -25.. manner was only slightly more constant per kilogram of body weight than in total grams per period. As shown in Table IX the excretion of sodium in the feces of the two subjects ranged from traces to 0.019 grams per kilogram. Table X indicates that there was no correlation between the intake of sodium from the medium protein diet and the amount of sodium excreted in the feces of the two subjects. Both children excreted a large proportion of the sodium from the medium protein diet in the urine. Subject D eliminated 90.5% and B, 92.4% of the fOOd sodium by way of the kidneys. The period excretion of sodium in the urine ranged from 0.960 to 1.58? grams for D and 0.992 to 1.469 grams for B. Table II indicates that there was also a wide range in urinary sodium per kilogram of body weight. Both for tota1.and for the «kilogram figures the per cent variation from the average for D and B was from +48.5% to -15.9% and +£5.65 to -l4.5% reapect- ively. Averaging the three day figures fer urinary elimination smoothed out some of the daily variation and the period excre- tion of sodium in the urine closely paralleled the intake. Graph No. 1 reveals the close relationship between the intake and the urinary sodium on bath diets for the two subjects. This rela- tionship is confirmed in Table X which indicates that the co- efficient of correlation between intake and urinary sodium per kilogram of body weight was as high as 0.915 on the medium pro- tein diet. Practically all the sodium injested on the medium protein diet was absorbed by the children. Subject D absorbed —26- 66H0.0 6660.0 6N60.0 HN60.0 N000.0 6660.0 60.6H NH 6000.0 HN60.0 6N60.0 6H60.0 6000.0 0660.0 60.6H HH H600.0 H660.0 6H60.0 0H60.0 6000.0 6660.0 60.6H 0H 6N00.0- N660.0 6660.0 6660.0 6000.0 0660.0 66.6H 6 6HH0.0 6660.0 N660.0 6660.0 6000.0 6660.0 66.6H 6 H000.0- 0660.0 6660.0 H660.0 6H00.0 6660.0 60.6H 6 6N00.0 6660.0 6660.0 0660.0 6000.0 6660.0 66.6H 6 H600.0 6660.0 0H60.0 6060.0 6000.0 H660.0 00.6H 6 HH60.0 6600.0 N660.0 6H60.0 6000.0 6H60.0 66.6H 6 H600.0 6660.0 6660.0 N660.0 HH00.0 6600.0 66.6H 6 6H00.0- 0060.0 6660.0 6H60.0 6H00.0 6H60.0 00.6H N 6NH0.0 6660.0 6660.0 6660.0 6H00.0 N060.0 00.6H H 00H0.0 6660.0 0660.0 6660.0 N000.0 0660.0 06.6H NH 0H00.0 6H60.0 6H60.0 6060.0 6000.0 6N60.0 06.6H HH 6600.0 H660.0 6060.0 6060.0 0000.0 H660.0 H6.6H 0H NN00.0 N660.0 HH60.0 0H60.0 H000.0 6660.0 66.6H 6 0600.0 6660.0 6660.0 6660.0 H000.0 6660.0 66.6H 6 N000.0 6660.0 6660.0 N660.0 6000.0 6660.0 66.6H 6 6600.0 6660.0 0660.0 6N60.0 H000.0 6660.0 H6.6H 6 6600.0 6660.0 666 .0 6660.0 6000.0 0660.0 66.6H 6 6600.0 6060.0 N660.0 6660.0 6000.0 6060.0 06.6H 6 6600.0 6660.0 6660.0 6660.0 H000.0 6660.0 H6.6H 6 6600.0 6660.0 H660.0 6660.0 6H00.0 6H60.0 66.6H N 6N00.0- H660.0 HN60.0 6060.0 NH00.0 6660.0 66.6H H 066% 066% 060% 06:66 068.66 068% 066606 00H66660m 6066660666 H0606 ocan 00006 omean 666606. 00Huom 606600 00666 666 660H66 6006 60 666006H6 666 66066666 20H006 XH mAmdnH. .0066 66Hm .0066 .002 .6066 66H6 .0066 .006 0060 6006606 -27- 666.0 N00.0 600.0 H600.0 66H0.0-6000.0 0H . 666.0 600.0 0H0.0 6H60.0 6H60.0-6660.0 0H 666.0 600.0 600.0 6660.0 6660.0-6N60.0 0H H06.0 600.0 600.0 N660.0 6660.0-HN60.0 0H 666.0 000.0 000.0 6000.0 6000.0-H000.0 0H 600.0 0H0.0 6H60.0 6660.0-0660.0 0H H6H.0 H00.0 600.0 6600.0 6NH0.0-H000.0 6H 666.0 600.0 0H0.0 6660.0 6660.0-0660.0 6H HH6.0 600.0 HH0.0 6H60.0 N60.0-NN60.0 6H 6H6.0 600.0 0H0.0 6000.0 6060.0-6H60.0 6H 666.0 000.0 H00.0 6000.0 6H00.0-H000.0 6H 600.0 0H0.0 N660.0 N060.0-6660.0 6H oxdpuw 6663. nonno noflpdfibmu mama .awmonHM pom moamgam nowpaHouhoo undcnwpw vuducapm oapmfispwud madam aw owddm mo .02 60 66060666000 Hmon2.wmom mOHE¢MmOAHM mmm ZOHBZHHQm 934.30H9mmomm¢ .ZOHammOxm QOHmum maHK.mM0? 9 . . . . . . qu: z. (z . 3.5.2. (2 , u a 6.03.3.6 _ . . . . \r , _ . _ . _ . . . . . ,0 , . 6 T 23...on :9: 25.60.... 13.32 . . . . . qu: 2. <2 ” 3.5.2. (2 . a Puuwaam . . I . A . ._ ------------ 2.3.0."... 1.9.... -. _ z..utv¢m..1:.ou1 , 20....ua0xw >mov n ZO_._.n_mme< OZ< w¥<._.2_ N .02 Il<¢0 m PUMfimDm ZEPONE EDEN} o hUMfimDm Z_M.PO¢n_ 33.0m: 2 D .OOW V swVao .9 "2 -51.. protein diet were comparable in most respects to those on the medium protein diet. The period intake of sodium, though slightly higher than on the medium protein diet, showed a similar varia- tion on the higher level of protein. Subject D injested from 1.094 to 1.498 grams of sodium daily and B consumed between 1.205 and 1.648 grams per period. The high protein diet also exhibited an appreciable difference in the period intake of sodium per kilogram of body weight, as shown in TableIX. The per cent variation from the average for both total and per kilogram intake was from.+20.2% to ~12.5% and «£0.2% to 12.2% for subjects D and B reSpectively. In accordance with the medium protein diet, the average amount of sodium per kilogram of body weight eaten by the two subjects was similar. Subject D received an average of 0.0715 grams and B 0.0720 grams per period. I Fecal excretion of sodium was lower on the high than, on the medium protein diet and there was not as great a variation between periods. Subject D excreted an average of 66.7% and B 45.0%‘1ess sodium on the high than on the medium protein diet. This was true even though the high.protein diet provided 8.7% more sodium than did the medium protein. The range in fecal sodium was from 0.001 to 0.018Igrams per period on the high pro- tein level - a much smaller range than on the medium protein diet. Tables VIII and IX indicate that the amount of fecal sodium was small and the period excretion of fecal sodium was not con- stant either for the individual subjects or when the two were compared. similar to the medium protein level the high protein diet did not show a correlation between intake and fecal excre- tion of sodium as indicated in Table X. -52.. Sodium output in the urine on the high protein diet, like that on the medium, represented a major portion of the amount injested in the food. Period elimination varied from 1.012 to 1.559 grams for D and 0.994 to 1.418 grams for B. As liown in Table IX there was also a considerable variation in urinary output of sodium per kilogram of body weight. The var- iation from the average urinary excretion of sodium was from +17.5% to -ll.5% and +14.5% to -19.7% reapectively, for subjects D and B. Graph No. 1 demonstrates the close relationship between the injestion and urinary excretion of sodium for both subjects. As shown in Table X there was a high correlation between intake and sodium in the urine on the two diets. Since the injestion of sodium was higher and fecal out- put lower on the high protein diet than on the medium the absorbed sodium was slightly higher also. The two bqys absorbed between 98.8% and 100.00% of the food sodium on the higher level of pro- tein. Tables VIII and IX indicate that the absorption and intake were similar on both diets and Graph No. 2 that on the high.pro- tein diet also, absorption of sodium closely paralleled the intake. The high coefficient of correlation between intake and absorption on the medium protein diet was simulated on the high protein as shown in Table X. A closer relationship existed between the retention of sodium by the two children, on the high.than on the medium pro- tein diet. Variation in sodium retention ranged from 0.017 to 0.512 grams per period on the high protein diet. Table IX ins dicates that there was a similar wide variation on a kilogram -53.. basis. As opposed to retention on the medium protein diet, the sodium retained on the high protein showed a positive correlation with intake. There seemed to be some indication as shown in Table VIII, that as the intake increased the per- cent of sodium retained increased also. This might imply that when the sodium intake was sufficiently high the intake, absorp- tion and retention were parallel and possibly that even the high protein diet did not supply the optimun amount of sodium. The chief difference in the sodium metabolism of the two subjects on the high protein diet from that on the medium seemed to be that the intake was slightly higher, the fecal excretion lower and, therefore, absorption was more complete. Comparison of Sodium and Chlorine Metabolism A number of investigators have felt that there was a close relationship between sodium and chlorine metabolism (25, 51, 52, 46). Wiley, Wiley and waller working with hospital- ized patients whose kidney function was impaired, made the following statement: "No relationship could be established be- tween the excretion of the various bases. It appears, however, that the excretion of chloride parallels the output of sodium more closely than any other base" (46). The latter observation was confirmed with respect to the two pre—school children in this study on both the medium and high protein diets. A comparison of Graphs No. 5 and 4 indicate that the two children responded similarily with reSpect to sodium and 2.29.... .-....o:.. ..o no 29550.1»? . . .5 ho axfiz. (2 no zo.,...m¢0xu ..<...o... «(z modxchzill 2.9.35.1; 2.59... 223.2 . _ . . . _ . _ . _ . _ . . . _ a how 303m _ evomLoL .Aow n a PUMfiflDm . 4 . 2...... 22...: -uz.mo.....o oz< 355%. ....o 20.5.5.0 ozl.< 9.5.2. n .02 In<¢o saves a o. a 7. .V.NJ1—- .7 . -55- Zakomm 10:... Z_m.r0mn. 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