Growth of newborn, term infants fed soy formulas for 1 year.

Few studies have measured long-term growth in infants fed soy protein-based formulas. The effect of nucleotide (NT) supplementation of soy protein-based infant formulas on growth is unknown. Growth was therefore evaluated in healthy term infants fed a soy protein-based formula (SOY; n = 73), SOY with added NT (72 mg added NT/L) at human milk (HM) levels (SOYN, n = 73), or mixed feeding (MF, n = 67) in a randomized, masked, parallel 1-year feeding study. The MF group (a nonrandomized reference group) was fed HM exclusively from birth to 2 months of age followed by HM and/or a standard milk-based formula (Similac with Iron with no supplemental NTs) to 1 year of age. Results indicated that growth (weight, length, and head circumference) was normal and comparable among the three groups. All three groups had similar plasma albumin (at 2 months of age) and hemoglobin levels (at 12 months of age). Thus, this study demonstrated similar growth in the first year of life among infants fed MF feeding or soy formula with or without supplemental NTs.     

Bone mineral metabolism in full-term infants fed human milk, cow milk-based, and soy-based formulas.

OBJECTIVE--To study the hypothesis that ingestion of a modified soy-based formula with an improved mineral suspension system may result in bone mineral content similar to that observed in infants fed human milk or cow milk-based formulas. DESIGN--Prospective, self-selected group of infants fed human milk randomized between the two formula-fed groups. SETTING--University-based hospital nursery and follow-up. PARTICIPANTS--Fifty-six normal, healthy, full-term infants, free of major malformations or disorders, including 17 infants fed human milk, 19 infants fed a cow milk-based formula, and 20 infants fed a soy protein formula were followed up to 6 months' postnatal age. The soy-based formula studied was modified to improve the suspendability of the minerals. INTERVENTIONS--Infants were fed human milk or the study formula for the first 4 months, at which time beikost was permitted. Infants fed human milk received vitamin supplementation to provide 400 IU of vitamin D per day. MEASUREMENTS--Anthropometric variables, serum calcium, magnesium, phosphorus, alkaline phosphatase, and parathyroid hormone levels were measured at enrollment, and at 8, 16, and 24 to 26 weeks' postnatal age. Bone mineral content at the distal third radius site was measured with single photon absorptiometry at these times. Growth in the infants did not differ significantly among the groups. There was no significant difference in serum calcium, magnesium, alkaline phosphatase, or parathyroid hormone concentrations among the infants during the study. Serum phosphorus was significantly lower at 8 weeks in the group fed human milk than in that fed the cow milk-based formula. Bone mineral content at 16 and 24 to 26 weeks was higher in the group fed the soy-based formula than in that fed human milk, and bone width was also higher at 16 weeks in the infants fed the soy-based formula. CONCLUSIONS--Improving the suspendability of the mineral system in the soy formula results in bone mineralization in infants fed the soy-based formula similar to that measured in infants fed human milk and cow milk-based formula. We suggest that the suspendability of the minerals used is an important variable in the interpretation of the effect of feedings on the bone mineral status of infants.     

Diet and bone mineral content at term in premature infants

Premature infants are at risk of developing metabolic bone disease mainly because of low calcium and phosphorus intake. We have examined the effect of different mineral supplements on bone mineral content at term in 127 premature infants with gestational age <32 wk in a double-blinded randomized trial. We used either phosphate supplementation of human milk as recommended by the European Society of Pediatric Gastroenterology and Nutrition or fortified supplementation with protein, calcium, and phosphorus or preterm formula as recommended by the American Academy of Pediatrics. The intervention period was from 1 week old until 36 wk of gestational age, and the infants were fed approximately 200 mL x kg(-1) x d(-1). Bone mineral content was measured at term by dual-energy x-ray absorptiometry scan. Surprisingly, neither phosphate, fortifier, nor preterm formula supplementation had any significant effect on bone mineral content at term compared with infants fed their own mother's milk only. There was a tendency to higher total bone mineral content in infants fed preterm formula compared with infants fed their own mother's milk only (p = 0.05), but when the bone mineral content was corrected for the size of the infant, there was no difference (p = 0.68). Infants fed preterm formula had a significantly higher weight at term compared with infants fed their own mother's milk only (p = 0.02), but did not differ significantly in length or head circumference. In a regression analysis, the amount of supplemented phosphorus was significantly associated with weight at term (p = 0.008). We conclude that when feeding 200 mL x kg(-1) x d(-1), mineral supplementation of human milk or use of preterm formula does not significantly improve bone mineralization outcome at term.     

Bone mineral content in term and preterm appropriate-for-gestational-age infants.

Photon absorptiometry adapted for use in small infants was utilized to measure bone mineral content in 42 term and 30 perterm appropriate-for-gestational-age infants. BMC at birth correlated significantly with gestational age and birth weight. Sequential measurements of BMC in premature infants during the first three months showed that the postnatal increase in BMC was significantly less than the BMC expected in utero. We speculate that decreased intake of calcium and phosphate effects postnatal bone mineralization in premature infants.     

Use of soy protein-based formulas in infant feeding

Soy protein-based formulas have been available for almost 100 years. Since the first use of soy formula as a milk substitute for an infant unable to tolerate a cow milk protein-based formula, the formulation has changed to the current soy protein isolate. Despite very limited indications for its use, soy protein-based formulas in the United States may account for nearly 25% of the formula market. This report reviews the limited indications and contraindications of soy formulas. It will also review the potential harmful effects of soy protein-based formulas and the phytoestrogens contained in these formulas.     

Longitudinal changes in the bone mineral content of term and premature infants

With the use of photon absorptiometry, bone mineralization was measured at birth and 8 and 16 weeks after delivery in 12 very-low-birth-weight premature (mean +/- SD gestational age, 31 +/- 1.5 weeks) infants who required minimal medical support. Simultaneously, 19 healthy term infants were studied. Throughout the study, each neonate received modified 84-kJ/30 mL formula containing no added calciferol. The recommended daily allowance (400 IU) of calciferol was given to each infant as an oral supplement. Serum 25-hydroxyvitamin D, calcium, phosphorus, and parathyroid hormone concentrations were monitored biweekly and were normal. Bone mineral content and bone width significantly differed at birth between the term and premature infants. However, by 16 weeks after delivery, the premature infants had exceeded the bone mineral status of the term infants at birth, and their bone mineral content was not significantly lower than that of the term infants. These data indicate improved bone mineralization as compared with previously reported data from very-low-birth-weight neonates.     

Effects of bilirubin on visual evoked potentials in term infants

Abstract To determine bilirubin-induced neurotoxicity, serial visual evoked potentials (VEPs) of 72 infants with neonatal hyperbilirubinaemia and 22 controls were evaluated and compared in four sessions for 8 weeks after birth. The levels of maximal serum bilirubin were found positively related to the wave latencies of first VEP. Within 8 weeks after birth, the wave latencies were significantly prolonged in infants in the severe and moderate groups than in the controls. The amplitudes of VEPs were apparently lower in severe and moderate groups than in the control group only in the 1st week after birth. At 1 year, 4 of the 18 infants in the severe group had poor motor skills and one had general hypotonia.Conclusion These results suggest that bilirubin may affect the visual pathways, and that VEP is a useful adjunct to the neurological assessment of neonatal hyperbilirubinaemia.     

血清胆红素浓度对足月新生儿神经心理发育的影响

由于新生儿胆红素代谢特点,约50%~60%的足月儿于出生后2~3d内均出现黄疸[1],对患儿多数没有大的影响。但当血清胆红素浓度增高超过一定限度时可能影响患儿的神经心理发育,严重者可引起脑瘫[2]。但多大浓度会对新生儿中枢神经系统产生影响,其功能障碍是否随高胆红素血症治愈而恢     

Indices of protein metabolism in term infants fed either human milk or formulas with reduced protein concentration and various whey/casein ratios

Hyperaminoacidemia is evident in infants fed either whey-dominant or casein-dominant formula containing 2.2 g protein/100 kcal. We assessed protein metabolism in infants fed formulas with reduced protein contents and various whey/casein ratios. Term infants (n = 40) received either human milk or formula containing 1.8 g protein/100 kcal and whey/casein ratios 18:82, 34:66, or 50:50. At ages 4 and 8 weeks, growth indices and mean serum concentrations of retinol binding protein, albumin, total protein, and serum urea nitrogen were similar, as were mean plasma concentrations of total amino acids, total essential amino acids, and their ratio. Compared with infants fed human milk, those fed formula had plasma concentrations similar for valine, lysine, arginine, tyrosine, histidine, threonine, and free and total cyst(e)ine; elevated for phenylalanine, methionine, and citrulline; and depressed for taurine and tryptophan. Except for leucine, mean plasma amino acid values varied similarly among formula groups despite differences in intakes. Our data indicate that feeding formulas providing 1.8 g protein/100 kcal results in many indices of protein metabolism characteristic of human milk feeding. However, certain differences are noted, suggesting the need for further manipulation of specific amino acid patterns of infant formulas.     

Growth and adiposity of term infants fed whey-predominant or casein-predominant formulas or human milk

Growth, estimated composition of weight gained, and stool patterns of term infants who were fed either a whey-predominant formula or a casein-predominant formula in a random design and of breast-fed infants were compared. All infants (N = 111) were healthy, singleton products of uncomplicated pregnancies. Birth weights and other anthropometric measures in the first few days of life were not different among the three feeding groups. Formula or breast milk was the infants' principal source of energy from birth to age 16 weeks. Average energy intakes of formula-fed infants and change of intakes with age were similar in both groups at all ages. Feeding groups were not significantly different at any age in weight, length, weight or length gain, head circumference, skinfold measurements, upper arm fat area and muscle area, or estimated total body fat. Stools of infants on the whey-predominant formula differed from both the breast-fed and casein-predominant formula groups.     

Whey protein hydrolysate formula for infants with gastrointestinal intolerance to cow milk and soy protein in infant formulas

Twenty-one infants less than 6 months of age with gastrointestinal symptoms of cow milk and/or soy protein-based infant formula intolerance (diarrhea in 14, hematochezia in 16, emesis in 8, failure to thrive in 4, and colic in 10) were treated clinically with a whey protein hydrolysate formula. Six patients improved when placed directly on the formula, and 15 remained asymptomatic or improved when given the whey hydrolysate formula following initial treatment with a casein hydrolysate or elemental formula. Eighteen had supporting evidence of an allergic basis for their symptoms, including a family history of allergies in 6, a clinical challenge with the offending formula in 1, laboratory tests consistent with atopy in 11, and/or rectal biopsy with histologic allergic features in 7. The whey hydrolysate formula may be an acceptable alternative to soy or casein hydrolysate formulas in most infants with gastrointestinal symptoms of cow milk and/or formula intolerance.     

Effects of two levels of intake of chloride, potassium, and calcium on mineral and acid-base metabolism in premature infants

Growth (weight, length, mid-upper arm circumference), acid-base status, serum electrolyte levels, and selected parameters of urine (creatinine and electrolyte levels, urine pH, renal net acid excretion, levels of metabolites of aldosterone) were determined serially from the 10th to the 32nd days for 4 weeks in 21 premature infants (birth weight, 1,100-2,000 g) fed either formula A or formula B (formula B was formula A supplemented with chloride, potassium, and calcium). Premature infants fed formula B showed a higher weight gain (31 versus 28.2 g/day), a higher increment of middle-upper arm circumference (0.31 versus 0.24 cm/week), and a decreased renal net acid excretion (1.24 versus 1.92 mEq/kg/day). Almost all premature infants fed formula A and some with a high growth rate receiving formula B showed hypochloruria corresponding to chloride deficiency. Premature infants fed unsupplemented humanized formulas may have an inadequate intake of minerals.     

Effects of increased calcium and phosphorous formulas and human milk on bone mineralization in preterm infants

By photon absorptiometry, extrauterine bone mineralization was evaluated in preterm infants (less than 1,600 g birth weight) fed either a commercial premature formula containing 117 mg calcium, 58.5 mg phosphorus/100 kcal, the same formula containing higher phosphorus (82 mg/100 kcal), the same formula with higher calcium (140 mg Ca) and phosphorus (82 mg/100 kcal), or their own mother's milk. All infants had serum protein, albumin, calcium, phosphorus, bicarbonate, 25-hydroxyvitamin D, and alkaline phosphatase levels done at the start of the study and every 2 weeks until they weighed 1,900 g. At the start of the study, birth weight and gestational ages were similar in all four groups. There were no biochemical differences among the four groups except for a lower serum P in the human milk group. The human milk group had lower bone mineralization rate compared with the three formula groups. Bone mineral content was similar in the three formula-fed groups. However, only formulas containing 117 mg Ca and 58.5 mg P or 140 mg Ca and 82 P mg/100 kcal approximated intrauterine bone mineralization. Human milk fed infants did not approximate and were significantly different from the intrauterine rate.     

Kernicterus in term infants

Kernicterus is a frequent occurrence in Chinese term infants. In a previous study, the mean level of serum bilirubin of 152 kernicteric infants was 35.4 mg/dl (605.3 μmol/l) and the range was 22.3-50 mg/dl. More recently, three further term infants developed kernicterus and one exhibited bilirubin level of only 23.3 mg/dl. Features of haemolysis were lacking in 56.8% of these infants. Evidence of brain damage occurred in 26.5% in a former series and in 5.5% of the more recent study of those infants who developed bilirubinaemia exceeding 20 mg/dl. Such a high risk favours the present practice of exchange transfusion for rising bilirubin beyond 20 mg/dl (342 μmol/l) in Chinese term infants.     

Effects of dopamine infusion on plasma catecholamines in preterm and term newborn infants

Newborn infants (21 preterm and 13 term) received dopamine infusions at a low (2.5–3.4 g/kg per min) and/or high (5–10 g/kg per min) infusion rate and changes in plasma catecholamines were monitored. The mean baseline values for dopamine, noradrenaline and adrenaline were between 240 and 560, 125 and 144 and 62 and 82 pg/ml, respectively. During low-rate infusion of dopamine, there was a significant increase in plasma dopamine (20–100fold), noradrenaline (three- to five-fold) and adrenaline (threefold). Administration of dopamine at the high rate resulted in an even larger increase in the plasma catecholamines (dopamine, 100–300fold; noradrenaline, seven- to eightfold; adrenaline, four- to sixfold). In a double-log plot, there was a highly significant correlation between the plasma concentrations of dopamine and noradrenaline (r=0.77;P<0.001). In conclusion, infusion of dopamine in term and preterm newborn infants is accompanied by an enhanced sympatho-adrenal tone which may contribute to the cardiovascular effects of dopamine in these patients.     

Kernicterus in term infants

Kernicterus is a frequent occurrence in Chinese term infants. In a previous study, the mean level of serum bilirubin of 152 kernicteric infants was 35.4 mg/dl (605.3 mumol/l) and the range was 22.3-50 mg/dl. More recently, three further term infants developed kernicterus and one exhibited bilirubin level of only 23.3 mg/dl. Features of haemolysis were lacking in 56.8% of these infants. Evidence of brain damage occurred in 26.5% in a former series and in 5.5% of the more recent study of those infants who developed bilirubinaemia exceeding 20 mg/dl. Such a high risk favours the present practice of exchange transfusion for rising bilirubin beyond 20 mg/dl (342 mumol/l) in Chinese term infants.     

Vitamin D metabolism, mineral homeostasis, and bone mineralization in term infants fed human milk, cow milk-based formula, or soy-based formula

The purpose of this study was to evaluate mechanisms of mineral homeostasis and mineralization in term infants with recommended vitamin D intakes. Infants fed human milk (nine), cow milk-based formula (11), or soy-based formula (11) were studied at 2 weeks and at 2, 4, 6, 9, and 12 months of age. While receiving 400 IU of vitamin D, all infants maintained serum vitamin D concentrations higher or equal to normal adult concentrations, and serum 25-hydroxyvitamin D levels were maintained at or above normal adult levels. Serum 1,25-dihydroxyvitamin D concentrations were higher than those of adults in the formula-fed but not in the human milk-fed infants. Serum calcium and phosphorus values were similar in all groups; however, urine phosphorus excretion and urine calcium excretion were adjusted to intakes. Serum parathyroid hormone values were normal in all groups. Bone mineral content significantly increased with age similarly in all groups; however, an apparent plateau occurred at 6 months of age in all groups. Bone width steadily increased with age. Taken as a whole, these data suggest that the vitamin D-sufficient term infant fed human milk, cow milk-based formula, or the soy-based formula studied can regulate mineral metabolism within acceptable physiologic limits to attain similar levels of serum minerals and bone mineral content.