Bioavailability of iron in soy-based formula and its effect on iron nutriture in infancy

Soy products have been reported to inhibit absorption of nonheme food iron and fortification iron. Iron bioavailability from a soy formula (Prosobee-PP 710) (iron added as ferrous sulfate: 12 mg/L; ascorbic acid: 54 mg/L) was examined in 16 adult women using the extrinsic radioactive tag method. The geometric mean absorption from the soy formula was only 1.7%. The effect of this formula on iron nutrition in infants was studied in 47 healthy term infants weaned spontaneously before 2 months of age and who received the formula ad libitum until 9 months of age. For control, 45 infants received a cow's milk formula fortified with ferrous sulfate (iron: 15 mg/L; ascorbic acid: 100 mg/L), which has been shown to be effective in preventing iron deficiency, and 49 additional breast-fed infants were also followed. All babies received solid foods (vegetables and meat) starting at 4 months of age. Iron nutritional status was determined at 9 months. Infants fed soy formula and iron-fortified cow's milk had similar mean values of hemoglobin, mean corpuscular volume, transferrin saturation, free erythrocyte protoporphyrin, and serum ferritin; both formula groups differed significantly (P less than .05) from the breast-fed group in all measurements except free erythrocyte protoporphyrin. Anemia (hemoglobin less than 11 g/dL) was present in only 4.3% and 2.2% of infants receiving the soy and the fortified formulas, respectively, v 27.3% in the breast-fed group. These results indicate that soy formula, in spite of the lower iron bioavailability when measured in adults, is essentially as effective as iron-fortified cow's milk in preventing iron deficiency in infants.     

Food Intake and Growth of Infants between Six and Twenty-six Weeks of Age on Breast Milk, Cow's Milk Formula, or Soy Formula

ABSTRACT. In 59 normal infants attending well-baby clinics, food consumption was registered until 26 and growth until 52 weeks of age. They were either breast-fed or formula-fed with a cow's milk product or a soy protein product. The average consumption of breastmilk was 746, 796, 722 and 689 g/day at 6, 14, 22 and 26 weeks respectively. Bottle-fed infants received larger volumes, and at 6 and 14 weeks were the calculated total energy intakes significantly higher than in breast-fed infants. No differences were seen between the feeding groups with respect to length and the sum of four skin folds. The soy formula-fed children, who happened to be 200 g heavier at birth, had lower weight gains during the first 6 weeks than the other two groups. Thereafter, the average weights of the soy formula group did not differ from the other groups. At 3 months, the soy formula-fed children displayed a slower mineralisation and maturation of bone, but the difference was no longer significant when re-examined at 6 months. Formulas based on soy protein isolates seem to be acceptable as substitutes for cow's milk formulas in feeding normal infants.     

Prospective oral food challenge study of two soybean protein isolates in patients with possible milk or soy protein enterocolitis

The soybean protein isolate used in powdered soybean formula is hydrolyzed more extensively than the isolate which is used in liquid soybean formula in most commercial soybean formulas. Previous in vitro studies have shown differences in human antibody response to these soybean protein isolates. Therefore, a prospective clinical study was undertaken to determine if there were differences in adverse reaction rates to these soybean protein isolates. Forty-three patients with possible milk- and/or soy-protein enterocolitis were enrolled in this study. Patients had 3 separate oral food challenges; using milk formula, soybean powder formula and soybean liquid formula. Ten (23%) patients challenged with milk had positive challenges. Fourteen (33%) patients challenged with powdered soy formula had positive challenges while thirteen (30%) challenged with liquid soy formula had positive challenges. In the 10 patients with positive milk challenges, 6 (60%) had a positive soy challenge. In the group with positive soy challenges, 5 reacted to the powdered soy challenge done first, but not the second challenge with the liquid soy formula, and 4 patients reacted to the liquid soy formula challenge done first, but not the second challenge with the powdered soy formula. These results indicate that a significant number of patients with milk protein enterocolitis have soy protein enterocolitis. In addition, an order effect can be demonstrated in the soy challenges because of the tendency to react to the first soy challenge regardless of the type of isolate. These results suggest that a local immune effect caused by the protein may be present.     

Immune status of infants fed soy-based formulas with or without added nucleotides for 1 year: part 2: immune cell populations

BACKGROUND: Infants fed a soy protein isolate-based formula have immunization responses similar to breast-fed infants. However, cellular aspects of the immunologic development of soy-fed infants have not been studied extensively. Nucleotides added to milk-based formula benefit infant immune status, but reports of the immunologic effects of adding nucleotides to soy-based formula are not available. This study examines immune cell populations of infants fed soy protein isolate formulas with and without added nucleotides for 1 year. METHODS: Newborn, term infants studied in a masked 12-month feeding trial were assigned randomly to soy formula groups with and without added nucleotides (n = 94, n = 92). A nonrandomized human milk/formula-fed cohort (n = 81), was concurrently enrolled. Blood samples were collected at 6, 7, and 12 months. Thirty-two immune cell populations were characterized using three-color flow cytometry. Cellular markers were chosen to assess general pediatric immune status, emphasizing maturation and activation of B, T, and NK lymphocytes. RESULTS: All cell populations, number and percentages, were within age-related normal ranges. The only significant difference found between soy formula and human milk/formula-fed infants was the percentage of CD57 + NK T cells at 12 months (human milk/formula > soy formula, P = 0.034). There were significant differences at some time points between human milk/formula-fed and nucleotide-supplemented soy formula-fed infants in populations of lymphocytes, eosinophils, total T, helper T, naive helper, memory/effector helper, CD57 - T, and CD11b + CD8 + NK cells. None of the cell populations differed between infants fed soy formula versus soy plus nucleotides. CONCLUSIONS: Infants fed this commercial soy formula demonstrated immune cell status similar to human milk/formula-fed infants, consistent with normal immune system development. The addition of nucleotides to soy formula did not significantly change specific individual immune cell populations but tended to increase numbers and percentages of T cells and decreased numbers and percentages of NK cells.     

Growth of infants with IgE-mediated cow''s milk allergy fed different formulas in the complementary feeding period

Observational studies have shown that allergic infants, irrespective of the type of diet, show various degrees of growth depression in the first year of life. We investigated whether the type of milk in the complementary feeding period (6-12 months of age) is associated with differences in the increase of standardized growth indices (weight-for-age, WA; length-for-age, LA; and weight-for-length, WL, z-scores) in infants with cow's milk allergy (CMA). Infants with immunoglobulin E-mediated CMA breastfed at least 4 months and progressively weaned in the 5- to 6-month period were randomly assigned to three special formulas, a soy formula (n = 32), a casein hydrolysate (n = 31), and a rice hydrolysate (n = 30). A fourth, non-randomized group was made up by allergic infants still breastfed up to 12 months (n = 32). Groups were compared for WA, LA, and WL z-scores at 6, 9 and 12 months of age. All groups showed low WA and LA z-scores at 6 months of age. Infants fed hydrolyzed products showed a trend toward higher WA z-score increments in the 6- to 12-month period. The use of casein- and rice-based hydrolyzed formulas resulted in higher changes in WA compared with soy formula. Further research should be aimed at optimizing the dietary needs and feeding regimens for infants with CMA.     

Safety and efficacy of a new extensively hydrolyzed formula for infants with cow's milk protein allergy

Cow's milk protein allergy (CMPA) is best treated by complete elimination of cow's milk from the diet. For infants with CMPA who cannot be breast-fed, formulas based on extensively hydrolyzed proteins or on amino acids are the preferred substitutes for cow's milk-based formulas. In this study, we compared the tolerance and growth of infants with CMPA who were fed a new extensively hydrolyzed formula containing lactose (eHF) with those who were fed an amino acid formula (AAF). This was a prospective, multi-center, randomized, reference-controlled study. Seventy-seven infants <12 months old with suspected CMPA were enrolled. In 66 of these, CMPA was confirmed by oral challenge in a double-blind, placebo-controlled food challenge (DBPCFC) or by a medical history of severe allergic reaction to cow's milk and a positive skin prick test. These infants were then tested for their reaction to eHF and AAF in a DBPCFC. All infants tolerated both formulas and were randomized to receive either eHF (n = 34) or AAF (n = 32) for 180 days. Growth (weight, length, and head circumference) and tolerance [skin, gastro-intestinal, and respiratory tract symptoms of allergy] were evaluated after 30, 60, 90, and 180 days. There were no significant differences between the two groups in any of the growth measurements. Length and head circumference were similar to Euro-growth standards, but weight was slightly lower. Gastro-intestinal and respiratory tract symptoms of allergy were also similar in the two groups. However, whereas SCORAD scores for atopic dermatitis remained constant throughout the study in infants-fed eHF, there was a slight decrease in those fed AAF. Infants-fed eHF had significantly fewer incidents of vomiting than infants-fed AAF and a significantly higher frequency of soft stools. The new eHF is safe and well tolerated in infants diagnosed with CMPA.     

Immune status of infants fed soy-based formulas with or without added nucleotides for 1 year: part 1: vaccine responses, and morbidity

BACKGROUND: Immunologic development of soy-fed infants has not been extensively studied. Early studies of soy flour-based formulas showed decreased immunoglobulin production when soy protein intake was limited. However, there were no significant differences in rotavirus vaccine responses between breast-fed and soy protein isolate-based formula-fed infants. Nucleotides added to milk-based formula benefit infant immune status, but reports of the immunologic effects of adding nucleotides to soy-based formula are not available. This study evaluated immune status and morbidity of infants fed soy protein isolate formulas with and without added nucleotides for 1 year. METHODS: Newborn, term infants enrolled in a masked 12-month feeding trial were assigned randomly to groups fed soy formula with or without added nucleotides (n = 94, n = 92). A nonrandomized human milk/formula cohort (n = 81) was concurrently enrolled. Recommended immunizations were administered at 2, 4, and 6 months. Immune status was determined from antibody responses to Haemophilus influenzae type b, tetanus, diphtheria, and poliovirus vaccines at 6, 7, and 12 months. Parents and physicians reported morbidity data. RESULTS: All vaccine responses were within normal ranges. No response differences were observed between infants fed soy formula and those fed nucleotide-supplemented soy. However, antibody to H. influenzae type b at 7 and 12 months was higher in infants fed nucleotide-supplemented soy than in infants fed human milk/formula ( P = 0.007, P = 0.008, respectively). Human milk/formula-fed infants had higher poliovirus neutralizing antibody at 12 months than did soy-fed infants ( P = 0.016). Morbidity analyses showed that only physician-reported diarrhea was different among groups (groups fed human milk/formula had less diarrhea than did soy groups, P = 0.011). CONCLUSIONS: Term infants fed soy protein isolate-based formulas have normal immune development as measured by antibody responses to childhood immunizations.     

Milk protein intake in the term infant. II. Effects on plasma amino acid concentrations

The response of plasma amino acids to two bovine protein formulas with different protein content (1.6 and 1.2 g/100 ml containing 60% whey proteins and 40% caseins) was measured in term infants. These two groups of infants were compared with a group of infants that were breast-fed; all infants were fed ad libitum. Concentrations of threonine, valine and total branched chain amino acids reflected the amount of protein provided. Thus, the concentrations were higher in the higher protein formula infants from the second week of the study. In the low protein formula infants these amino acids were lower but differed from the infants on breast milk at eight and twelve weeks. Concentration of taurine was lower in the formula fed infants than they were in breast-fed infants at the end of the study. The valine/glycine ratio in the low protein formula group was lower than in the breast-fed group for the first four weeks of the study. After this time it was equal to that of the breast-fed group. These differences in plasma amino acid concentrations give further evidence that formulas now in common use for term infants provide a protein intake in excess of protein requirements after the first months of life.     

Parental counseling compared with elimination of cow's milk or soy milk protein for the treatment of infant colic syndrome: a randomized trial

Treating the infant colic syndrome by counseling the parents concerning more effective responses to the infant crying is compared to the elimination of soy or cow's milk protein from the infant's diet in a randomized clinical trial. Because symptoms of vomiting and diarrhea are not part of the infant colic syndrome, infants with these gastrointestinal symptoms were excluded from the study. Dietary changes were accomplished by either feeding the infants a hydrolyzed casein formula or by requiring mothers to eliminate milk from their diets. In phase 1 of the study, the group receiving counseling (n = 10) had a decrease in crying from 3.21 +/- 1.10 h/d to 1.08 +/- 0.70 h/d (P = .001). The crying in the group that received dietary changes (n = 10) decreased from 3.19 +/- 0.69 h/d to 2.03 +/- 1.07 h/d (P = .01), a level still greater than twice normal. The decrease in those receiving counseling was faster and greater than that of those given dietary changes (P less than .02). In the second phase of the study, group 2 infants were reexposed to cow's milk or soy protein and the parents received counseling. In this phase, counseling again decreased crying significantly from 2.09 +/- 1.07 h/d to 1.19 +/- 0.60 h/d (P = .05). No infant in the study who improved with changes in his or her diet had a significant increase in crying, with reexposure to soy or cow's milk protein.(ABSTRACT TRUNCATED AT 250 WORDS)     

Safety and efficacy of a new extensively hydrolyzed formula for infants with cow's milk protein allergy.

Cow's milk protein allergy (CMPA) is best treated by complete elimination of cow's milk from the diet. For infants with CMPA who cannot be breast-fed, formulas based on extensively hydrolyzed proteins or on amino acids are the preferred substitutes for cow's milk-based formulas. In this study, we compared the tolerance and growth of infants with CMPA who were fed a new extensively hydrolyzed formula containing lactose (eHF) with those who were fed an amino acid formula (AAF). This was a prospective, multi-center, randomized, reference-controlled study. Seventy-seven infants <12 months old with suspected CMPA were enrolled. In 66 of these, CMPA was confirmed by oral challenge in a double-blind, placebo-controlled food challenge (DBPCFC) or by a medical history of severe allergic reaction to cow's milk and a positive skin prick test. These infants were then tested for their reaction to eHF and AAF in a DBPCFC. All infants tolerated both formulas and were randomized to receive either eHF (n = 34) or AAF (n = 32) for 180 days. Growth (weight, length, and head circumference) and tolerance [skin, gastro-intestinal, and respiratory tract symptoms of allergy] were evaluated after 30, 60, 90, and 180 days. There were no significant differences between the two groups in any of the growth measurements. Length and head circumference were similar to Euro-growth standards, but weight was slightly lower. Gastro-intestinal and respiratory tract symptoms of allergy were also similar in the two groups. However, whereas SCORAD scores for atopic dermatitis remained constant throughout the study in infants-fed eHF, there was a slight decrease in those fed AAF. Infants-fed eHF had significantly fewer incidents of vomiting than infants-fed AAF and a significantly higher frequency of soft stools. The new eHF is safe and well tolerated in infants diagnosed with CMPA.     

Does breast-feeding influence intelligence quotients at 9 and 10 years of age?

The effect of breast-feeding on intellectual development remains controversial. We explored this relationship in a high socioeconomic population in which breast-feeding was supplemented with soy containing formulas at some time during the first year of life. As part of the 1988 National Institute of Child Health and Human Development school-based survey of two metropolitan Washington, D.C. counties to identify children in the 1978 to 1979 birth cohort who had been exposed to the chloride deficient formulas Neo-Mull-Soy and Cho-Free during infancy, information on breast-feeding was also obtained on children exposed to the chloridedeficient formulas and a group of control children exposed to other soy formulas. Because no differences in intellectual development were observed between the two groups, they were combined and the effect of breast-feeding on intellectual development at 9 and 10 years was assessed. There were 176 infants that received no breast-feeding and 342 who were breast-fed. The median duration of breast-feeding was 124 days (interquartile range, 42–248 days). There were no differences in birth weight, gender or race between the infants who were breast-fed and those who were not. The mean Weschler Intelligence Scale-Revised Full Scale IQ was 122 among those breast-fed compared to 118 among those that were not (P = 0.0008). However, following adjustment by linear regression for maternal education, paternal education and annual income the adjusted mean full scale IQ was 111 among the breast-fed and 110 among the non-breast-fed (P = 0.23). Further analyses limited to those exclusively breast-fed for the first 60 days failed to demonstrate any significant relationship between breast-feeding and IQ.     

Comparison of a partially hydrolyzed infant formula with two extensively hydrolyzed formulas for allergy prevention:A prospective, randomized study

The aim of this study was to compare the allergy‐preventive effect of a partially hydrolyzed formula with two extensively hydrolyzed formulas, in infants with a high risk for development of allergic disease. High‐risk infants from four Danish centres were included in the period from June 1994 to July 1995. Five‐hundred and ninety‐five high‐risk infants were identified. High‐risk infants were defined as having bi‐parental atopy, or a single atopic first‐degree relative combined with cord blood immunoglobulin E (IgE) ≥ 0.3 kU/l. At birth all infants were randomized to one of three different blinded formulas. All mothers had unrestricted diets during pregnancy and lactation and were encouraged to breast‐feed exclusively. If breast‐feeding was insufficient, one of the three formulas, according to randomization, was given during the first 4 months. It was recommended not to introduce cow's milk, cow's milk products, and solid foods until the age of 4 months. After the age of 4 months a normal unrestricted diet and conventional cow's milk‐based formula were given when needed. All infants were followed‐up prospectively with interview and physical examination at the age of 6, 12, and 18 months, and if any possible atopic symptoms were reported. If food allergy was suspected, controlled elimination/challenge procedures were performed in a hospital setting. Of 550 infants included in the study, 514 were seen at all visits and 36 were excluded owing to non‐compliance. Of 478 infants who completed the study, 232 were exclusively breast‐fed, 79 received an extensively hydrolyzed casein formula (Nutramigen), 82 an extensively hydrolyzed whey formula (Profylac), and 85 a partially hydrolyzed whey formula (Nan HA), during the first 4 months of life. These four groups were identical in regard to atopic predisposition, cord blood IgE, birthplace, and gender. Exclusively breast‐fed children were exposed less to tobacco smoke and pets at home and belonged to higher social classes, whereas the three formula groups were identical concerning environmental factors. The frequency of breast‐feeding was high; only eight (2%) children were not breast‐fed at all. The three formula groups were identical in regard to duration of breast‐feeding and age at introduction of formula and solid foods. No significant differences were found in the three groups of infants receiving formula milk regarding the cumulative incidence of atopic dermatitis or respiratory symptoms. The cumulative incidence of parental‐reported cow's milk allergy was significantly higher in children fed partially hydrolyzed formula (Nan HA) compared with extensively hydrolyzed formula (Nutramigen or Profylac) at 12 and 18 months (NanHA, 7.1%; Nutramigen, 2.5%; Profylac, 0%; p = 0.033). The cumulative incidence of confirmed cow's milk allergy was 1.3% (three of 232) in exclusively breast‐fed infants, 0.6% (one of 161) in infants fed extensively hydrolyzed formula (Nutramigen or Profylac), and 4.7% (four of 85) in infants fed partially hydrolyzed formula (Nan HA). Partially hydrolyzed formula was found to be less effective than extensively hydrolyzed formula in preventing cow's milk allergy, 0.6% vs. 4.7% (p = 0.05), but because of the small number of cases the results should be interpreted with caution. Compared with other similar studies the frequency of atopic symptoms was low, even though the dietetic intervention did not include either maternal diet during lactation or dietary restrictions to the children after the age of 4 months.     

A systematic review of the role of hydrolyzed infant formulas in allergy prevention

OBJECTIVE: To critically examine the published literature to determine whether feeding hydrolyzed infant formulas from birth has a role in allergy prevention. DATA SOURCES: We identified data through a MEDLINE search using allergy prevention and infant formulas as indexing terms. The search was restricted to 1985 through the present, English-language articles, and human subjects. STUDY SELECTION: Criteria for inclusion in the review were prospective controlled trials published in peer-reviewed journals. DATA EXTRACTION: Symptoms of allergy were defined and observed by health care providers (physicians and nurses). DATA SYNTHESIS: Nine published trials evaluated the use of extensively hydrolyzed formulas, 12 evaluated the use of partially hydrolyzed formulas in high-risk infants, and 1 evaluated the use of partially hydrolyzed formulas in an unselected infant population. The reports compared hydrolyzed formulas with breastfeeding, cow's milk formulas, soy formulas, and combinations thereof. The cohort of studies consistently showed reductions in the cumulative incidence of atopic disease from 12 to 60 months of age among high-risk infants fed extensively hydrolyzed casein formulas or partially hydrolyzed whey formulas vs cow's milk formulas. No studies showed an increase in allergy risk with any hydrolyzed formulas. CONCLUSIONS: Extensively hydrolyzed casein formulas and partially hydrolyzed whey formulas are appropriate alternatives to breast milk for allergy prevention in infants at risk. Because atopic disease in children cannot be predicted, the use of these formulas in the general population should be considered, and one must weigh cost, compliance, and long-term benefits.     

Essential fatty acid metabolism and requirements for LBW infants

Humans are unable to synthesize linoleic acid (LA) (18: 2ω-6) and α-linolenic acid (LNA) (18: 3ω-3). Most formulas provide ample LA, yet infants are at risk for ω-3 deficiency unless they are fed human milk. Neonates born at 30 weeks received human milk or were randomized to three formulas: formula A, based on corn oil, similar to old commercial formula; formula B, based on soy oil supplied LNA; or formula C, a product similar to B with added marine oil to provide docosahexaenoic acid (22:6 ω-3). The fatty acids of plasma and red blood cells had marked diet-induced differences. The rod photoreceptor tests demonstrated higher threshold and decreased sensitivity in the ω-3-deficient infants. Visual acuity also showed improved function of the brain cortex in the human milk and group C infants at follow-up at 57 weeks. These results suggest that ω-3 fatty acids are needed for optimal development of visual function.     

Whey predominant,whey modified infant formula with protein/energy ratio of 1.8 g/100 kcal: adequate and safe for term infants from birth to four months

BACKGROUND: Protein quality of breast milk is superior to that of formula proteins. To ensure that the protein intake is sufficient, starter formulas with conventional protein composition provide a protein/energy ratio of 2.2-2.5 g per 100 kcal to infants, which is much higher than that supplied with breast milk. Several studies have shown that formula-fed infants have higher plasma or serum urea concentrations than breast-fed infants do. We tested if feeding formulas with improved protein quality and a protein content corresponding to the minimum level that is consistent with international recommendations (1.8 g/100 kcal) allows patients to achieve normal growth and plasma urea concentrations. METHODS: Healthy term infants were enrolled into the study and were either breast-fed or randomly assigned to three formula-fed groups. Formula-fed infants received either a standard formula with a protein/energy ratio of 2.2 g/100 kcal, whereas the two other groups received formulas with a protein/energy ratio of 1.8g/100 kcal differing mainly by their source of protein. Subjects received breast milk or these formulas ad libitum as the sole source of energy from birth to four months of age in a controlled blind design (except for the breast-fed group). Anthropometric measurements (body weight and length) were obtained at birth, at 30, 60, 90, and 120 days. Energy and protein intakes were calculated from three-day dietary records. Blood was collected for biochemical measurements at 30, 60, and 120 days. RESULTS: No differences were found between the four feeding groups for weight- and length-gains or for body mass indices (BMI). No differences in energy intakes between the formula-fed groups could be found, whereas protein intakes were less in infants fed the 1.8 g/100 kcal formulas. Plasma urea levels of the infants fed the 1.8 g/100 kcal formulas were closer to those found in the breast-fed infants. CONCLUSION: Improvement of the amino acid profile permits a whey predominant starter formula with 1.8 g protein per 100 kcal to meet the needs of normal term infants during the first four months of life.     

Effects of Formula Protein Level and Ratio on Infant Growth, Plasma Amino Acids and Serum Trace Elements I. Cow's Milk Formula

Abstract. The optimum level and ratios of protein to be used in cow's milk formula has recently been under discussion. Healthy term infants were fed from birth exclusively human milk or a formula that varied in protein level or whey:casein ratio: (A) 1.4 g/dl; 55:45, (B) 1.5 g/dl; 55:45, (C) 1.3 g/dl; 55:45, (D) 1.4 g/dl; 60:40, (E) 1.4 g/dl; 20:80. Infants were followed for 12 weeks and blood samples were taken at 2, 4, 8 and 12 weeks. Anthropometric indices did not show any significant differences among groups. Plasma amino acid and BUN levels of the C group were closest to the breast-fed group, while the formula with the highest protein level (B) resulted in high values for some amino acids. When comparing the formulas with 1.4 g protein/dl, the high casein group had the lowest plasma tryptophan levels. Taurine was added to all formulas at a level similar to that of breast milk; plasma taurine levels were similar for all groups. All formulas contained 0.7 mg iron and 0.7 mg zinc/dl; no differences were found among the groups in hematological indices or serum trace elements. These data show that feeding a formula with 1.3 g protein/dl and 55:45 whey: casein ratio from birth will result in growth and metabolic indices similar to those of breast-fed infants, although some plasma amino acid levels are not identical, 1990.     

Effects of formula protein level and ratio on infant growth, plasma amino acids and serum trace elements. I. Cow's milk formula

The optimum level and ratios of protein to be used in cow's milk formula has recently been under discussion. Healthy term infants were fed from birth exclusively human milk or a formula that varied in protein level or whey: casein ratio: (A) 1.4 g/dl; 55:45, (B) 1.5 g/dl; 55:45, (C) 1.3 g/dl; 55:45, (D) 1.4 g/dl; 60:40, (E) 1.4 g/dl; 20:80. Infants were followed for 12 weeks and blood samples were taken at 2, 4, 8 and 12 weeks. Anthropometric indices did not show any significant differences among groups. Plasma amino acid and BUN levels of the C group were closest to the breast-fed group, while the formula with the highest protein level (B) resulted in high values for some amino acids. When comparing the formulas with 1.4 g protein/dl, the high casein group had the lowest plasma tryptophan levels. Taurine was added to all formulas at a level similar to that of breast milk; plasma taurine levels were similar for all groups. All formulas contained 0.7 mg iron and 0.7 mg zinc/dl; no differences were found among the groups in hematological indices or serum trace elements. These data show that feeding a formula with 1.3 g protein/dl and 55:45 whey: casein ratio from birth will result in growth and metabolic indices similar to those of breast-fed infants, although some plasma amino acid levels are not identical, 1990.     

Allergy to soy formula and to extensively hydrolyzed whey formula in infants with cow's milk allergy: a prospective, randomized study with a follow-up to the age of 2 years

OBJECTIVES: We conducted a prospective, randomized study to evaluate the cumulative incidence of allergy or other adverse reactions to soy formula and to extensively hydrolyzed formula up to the age of 2 years in infants with confirmed cow's milk allergy. STUDY DESIGN: Infants (n = 170) with documented cow's milk allergy were randomly assigned to receive either a soy formula or an extensively hydrolyzed formula. If it was suspected that the formula caused symptoms, a double-blind, placebo-controlled challenge (DBPCFC) with the formula was performed. The children were followed to the age of 2 years, and soy-specific immunoglobulin E antibodies were measured at the time of diagnosis and at the ages of 1 and 2 years. RESULTS: An adverse reaction to the formula was confirmed by challenge in 8 patients (10%; 95% confidence interval, 4.4%-18.8%) randomly assigned to soy formula and in 2 patients (2.2%; 95% confidence interval, 0.3% to 7.8%) randomly assigned to extensively hydrolyzed formula. Adverse reactions to soy were similar in IgE-associated and non-IgE-associated cow's milk allergy (11% and 9%, respectively). IgE to soy was detected in only 2 infants with an adverse reaction to soy. Adverse reactions to soy formula were more common in younger (<6 months) than in older (6 to 12 months) infants (5 of 20 vs 3 of 60, respectively, P =.01). CONCLUSIONS: Soy formula was well tolerated by most infants with IgE-associated and non-IgE-associated cow's milk allergy. Development of IgE-associated allergy to soy was rare. Soy formula can be recommended as a first-choice alternative for infants >or=6 months of age with cow's milk allergy.     

Sodium and potassium metabolism in infancy]

BACKGROUND: Recommendations for the concentration of most nutrients in infant formulas are based on their concentration in human milk. Industry succeeded in adapting sodium and potassium content in infant formulas to concentration found in human milk. Whether this adaptation affects on infants' mineral balances was studied in breast-fed and artificially-fed infants. METHODS: Sodium and potassium balances were performed in 16 term male infants from their 3rd until their 17th week of life. The balances were performed at home and comprised up to five periods in intervals of three to four weeks. Each balance period consisted of subsequent three 24 h collections of milk, stool and urine samples. Ten infants were breast-fed, six received an adapted infant formula supplemented with copper, zinc and iron. RESULTS: The breast-fed infants got a mean intake of 1 mmol Na/kg b w x day and a mean intake of 1.8 mmol K/kg b w x day. Man retention was 0.4 mmol Na and 0.7 mmol K/kg b w x day. The formula-fed infants received 1.9 mmol Na/kg b w x day and 2.1 mmol K/kg b w x day. Na- and K-retention in this group was 0.5 and 0.6 mmol/kg b w x day respectively. Although sodium intake in the formula-fed infants was nearly twice as much as in the breast-fed infants the difference in sodium retention was only small (0.4 vs 0.5 mmol/kg b w x day). The formula-fed infants got more potassium than the breast-fed infants, but potassium retention was the same in both groups. CONCLUSIONS: With the adapted infant formula of this study the artificially fed infant was as well supplied with sodium and potassium as the breast-fed infant. A further reduction of the sodium concentration seems not to be useful.     

Neutrophil and small intestinal lymphocyte migration after Salmonella typhimurium infection: impact of fermentable fiber

OBJECTIVES: Formula-fed infants have more episodes of acute diarrhea and intestinal infection than do breast-fed infants. Nutrient additions to infant formula that could confer some of the immune benefits of breast milk to formula-fed infants are currently under investigation. This study examined the impact of enteral formulas supplemented with fermentable substrates on small intestinal lymphocyte and neutrophil migration in piglets infected with Salmonella typhimurium. Small intestinal proinflammatory cytokine messenger RNA abundance and in vitro lipopolysaccharide-stimulated interleukin-6 release in whole blood were assessed. METHODS: Piglets were randomized to receive sow milk replacer formula supplemented with methylcellulose (control), soy polysaccharides (SPS) or fructooligosaccharides (FOS). On day 7, half of the piglets were infected with S. typhimurium. Intestinal lymphocyte, neutrophil and whole blood samples were obtained on day 14. RESULTS: After infection, there was decreased lymphocyte migration in the control group but not in the SPS and FOS groups. The SPS group had greater neutrophil migration compared with the control and FOS groups, regardless of infection. Small intestinal abundance of proinflammatory cytokine messenger RNA was not significantly changed by either infection or diet. Blood from the FOS group challenged with lipopolysaccharide for 2 hours exhibited decreased interleukin-6 production compared with blood from the control and SPS groups, regardless of infection. CONCLUSIONS: Supplementation of enteral formulas with SPS maintains the migratory function of small intestinal lymphocytes while increasing that of neutrophils.