Longitudinal zinc balances in breast-fed and formula-fed infants

Longitudinal zinc (Zn) balance studies were performed under domestic conditions in term breast-fed (n = 10), term formula-fed (n = 5; Zn concentration in the formula: 4 mg/l) and preterm formula-fed (n = 3) infants during the first 17 weeks of life. Samples of milk, urine and feces were analyzed by atomic absorption spectrometry. The median daily Zn intake in breast-fed infants decreased from 0.592 (0.457-0.829) mg Zn/kg body weight to 0.151 (0.095-0.304) mg Zn/kg body weight in the first 17 weeks of life; comparable values for bottle-fed term infants were 0.58 (0.511-0.701) and 0.674 (0.529-0.731) mg Zn/kg body weight. The median percent retention of Zn intake was 27 (-60 to 81.4)% in breast-fed infants and 21.5 (-42 to 64)% in formula-fed infants. In view of the urinary and fecal Zn losses measured, a daily intake of 0.3-0.5 mg Zn/kg body weight is considered to be sufficient to ensure a Zn retention equivalent to breast-fed infants. This requires a Zn concentration of 2-3 mg/l of Zn depending on milk volume intake.     

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.     

Renal excretion of calcium and phosphate in preterm and term infants

We studied urinary phosphate and calcium excretion in preterm and term infants during the first 3 months of life. The infants were mainly breast-fed, and the average phosphate intake ranged between 0.5 and 1 mmol/kg/day. During the first week of life urinary phosphate excretion was significantly higher in preterm than in term infants, whereas parathyroid hormone values were the same. After the first week of life urinary phosphate and calcium excretion were the same in preterm and term infants. Fractional excretion of phosphate was low (range 1% to 6%). In both groups calcium excretion was low during the first weeks of life, and increased thereafter to 5 and 3 mmol/1.73 m2/day, respectively. The urinary calcium/creatine ratio generally exceeded 2.0 (mmol/mmol) in preterm infants after the second week of life. These results are compatible with a state of relative phosphate deficiency, resulting in an adaptively low urinary phosphate excretion and an inability to form bone minerals, and therefore relatively high urinary calcium excretion.     

Iron status in exclusively breast-fed infants.

The aim of this study is to evaluate the iron nutritional status of infants breast-fed exclusively and for a prolonged period in relation to their growth rate and dietary changes. Forty subjects (25 breast-fed; 15 formula-fed) were studied from 0 to 9 months of age. Milk (human or formula) was the only source of food during the first 6 months. From the sixth month onward mothers were instructed to use iron- and ascorbic acid-rich foods to supplement breast-feeding. At the ninth month, prevalence of anemia was 27.8% in the breast-fed group and 7.1% in the formula-fed group. Storage iron was absent in 27.8% of the breast-fed infants vs none of the formula-fed infants. These findings reinforce the recommendation that breast-fed infants be given supplemental iron from the fourth month of life.     

Infant-feeding practices and their relationship with diarrheal and other diseases in Huascar (Lima), Peru

Longitudinal studies of the feeding practices and morbidity from infectious diseases of 153 Peruvian newborns from an underprivileged, periurban community were completed during their first year of life. Feeding practices were assessed by monthly questionnaires, and illnesses were identified by thrice-weekly, community-based surveillance. All infants were initially breast-fed, but only 12% were exclusively breast-fed at 1 month of age. At 12 months of age, 86% of children still received some breast milk. Incidence and prevalence rates of diarrhea in infants younger than 6 months of age were less among those who were exclusively breast-fed compared with those who received other liquids or artificial milks in addition to breast milk. The diarrheal prevalence rates doubled with the addition of these other fluids (15.2% v 7.1% of days ill, P less than .001). Infants for whom breast-feeding was discontinued during the first 6 months had 27.6% diarrheal prevalence. During the second 6 months of life, discontinuation of breast-feeding was also associated with an increased risk of diarrheal incidence and prevalence. Upper and lower respiratory tract infections occurred with lesser prevalence among exclusively breast-fed younger infants. The prevalences of skin infections by category of feeding practice were not as consistent, but exclusively breast-fed infants tended to have fewer skin infections during the initial months of life and older infants who continued to breast-feed had fewer infections than those who did not. None of the results could be explained by differences in the socioeconomic status of the infants' families.     

Development of the intestinal bacterial composition in hospitalized preterm infants in comparison with breast-fed,full-term infants

The establishment and succession of bacterial communities in hospitalized preterm infants has not been extensively studied. Because earlier studies depended on classical cultural techniques, their results were limited. This study monitored the establishment and succession of the neonatal microbiota in the first weeks of life by analyzing the 16S rDNA variety in fecal samples applying PCR-denaturing gradient gel electrophoresis (PCR-DGGE). Fecal samples from 29 preterm infants hospitalized in a neonatal intensive care unit, including samples from antibiotic-treated infants and one with neonatal necrotizing enterocolitis, were subjected to PCR-DGGE analysis. Daily DGGE profiles from all preterm infants during the first 4 wk were obtained and analyzed. In addition, feces of 15 breast-fed, full-term infants and a variety of clinical bacterial isolates were examined and compared with the PCR-DGGE profiles of the preterm infants. During the first days of life, the DGGE profiles were rather simple but increased in their complexity over time. It became obvious that not only the intraindividual band-pattern similarity increased over time, but also the interindividual. During the observation period, similarity values (Cs) increased in each preterm infant from 0 to 80%, whereas interindividual Cs increased from 18.1 to 57.4%, revealing the acquisition of a highly similar bacterial community in these infants. In contrast, Cs-values obtained for breast-fed, full-term infants were rather low (11.2%). Escherichia coli, Enterococcus sp., and Klebsiella pneumoniae were the bacteria most commonly found in all preterm infants. The interindividual bacterial composition in hospitalized preterm infants is more similar in comparison with breast-fed, full-term infants and is not necessarily influenced by birth weight, diet, or antibiotic treatment.     

Urinary excretion of epidermal growth factor and transforming growth factor-alpha in breast-fed and formula-fed infants

Urinary epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-α) concentrations were determined by radioimmunoassay in a longitudinal study analyzing 348 24-h urine specimens of 32 infants (16 breast-fed, 16 formula-fed) during the first 16 weeks of life. EGF excretion showed a statistically significant increase from 6.0 ±2.5 to 14.1±4.9 μg/g creatinine (mean± 1 SD) during the investigation period. TGF-α levels were fairly constant throughout this period. Comparing breast-fed infants, with more than 100-fold higher ingestion of EGF and TGF-α, with formula-fed infants, no significant differences in urinary EGF and TGF-α excretion were observed. These results do not rule out a systemic effect of EGF and TGF-α after intestinal absorption in breast-fed infants. The results suggest, however, that urinary EGF and TGF-α originate mainly from sources other than intestinal absorption.     

A study of the growth of 200 newborn babies for a period of 6 months according to the type of nutrition

Two hundred newborn babies were followed up for 6 months to monitor their weight, height, head circumference and skinfold thickness to assess the effects of exclusive breast-feeding, mixed feeding, bottle feeding and socio-economic factors on these parameters. Of the 200 babies, 90% were breast-fed upon discharge, and 83 (46%) commenced mixed feeding within the first 6 weeks. Inadequate breast-milk was the main reason given for starting mixed feeding (63.9%). Weight at 6 months was significantly greater in breast-fed infants compared with those who were only bottle-fed. Skinfold thickness at 6 months was also greater in breast-fed infants than in the other nutrition groups.     

Motilin and Infantile Colic

ABSTRACT. Two hundred and nineteen infants, consecutively born, took part in a prospective study of infantile colic from birth to 12 weeks of age. The prevalence of infantile colic in this group was 17.4%. S-motilin was studied in 78 term infants (19 with and 59 without infantile colic) at birth (cord blood), at one day, and at 6 and 12 weeks of age, respectively. Basal motilin levels were raised both in cord blood (p<0.01) and in blood from neonates (p<0.001) who developed colic as well as in 6 week (p<0.05) and in 12-week-old infants with colic (p<0.01). Formula-fed infants with colic had higher basal motilin levels than formula-fed controls at 6 and 12 weeks of age (p<0.05). Breast-fed infants with colic had higher basal motilin levels than breast-fed controls at 12 weeks of age (p<0.05). The raised levels of motilin from the first day of life in infants who develop infantile colic might indicate that the gastrointestinal tract is affected in infants with infantile colic, before any symptoms of colic appear.     

Changes in plasma lipoproteins from first day to third week of life in healthy breast-fed infants. II. Fatty acid composition of lipoprotein triglyceride- and cholesterol esters

The fatty acid composition of plasma lipoprotein-triglyceride (TG) and -cholesterol ester (CE) was studied in seven healthy breast-fed infants three times during the first day and on the third, sixth and twenty-first days of life. The major finding was a two-fold increase in the linoleic acid weight percent of plasma lipoprotein-TG and -CE between the first and third weeks of life. This increase could best be explained by the ingestion of breast-milk rich in linoleic acid.     

Trace elements (copper, zinc, manganese, and selenium) in plasma and erythrocytes in relation to dietary intake during infancy

All determinations of copper, zinc, manganese, and selenium were performed with a flameless atomic absorption spectrophotometer. Seventy-three full-term infants aged 1 to 52 weeks were divided into three age groups. Each age group contained two subgroups, breast-fed and formula-fed. No statistically significant differences between formula-fed and breast-fed subgroups were found in regard to the levels of copper and zinc in plasma and erythrocytes. At 1 to 5 weeks of age, the manganese concentration of erythrocytes was higher in formula-fed than in breast-fed infants (p less than 0.001). This might be due to the high dietary intake of this element in the formula-fed subgroup. On the other hand, plasma selenium concentrations were significantly higher in breast-fed than in formula-fed infants of all ages (p less than 0.01 at 1 to 5 weeks and p less than 0.05 at 6 to 52 weeks). This suggests that selenium compounds are biologically more available for infant nutrition in breast milk than in formula.     

Artificial feeding and hospitalization in the first 18 months of life

The association between type of feeding and hospitalization during the first 18 months of life was examined among 1,058 infants from Jing-An district, Shanghai, People's Republic of China. Infants who had never been fed with mother's milk were categorized as artificially fed; the remainder were breast-fed. The rate of hospitalization for first episodes of respiratory infections during the first 18 months of life for the artificially fed infants was 18.0% v 11.2% for the breast-fed infants (P less than .01). Multiple logistic regression analysis demonstrated that the adverse effect of artificial feeding on the hospitalization rate for respiratory infections was independent of birth weight, father's education, passive smoking, and any case(s) of chronic respiratory disease in the family. The adjusted odds ratio for the artificially fed infants compared with the breast-fed infants was 2.11. The artificially fed infants were also hospitalized more frequently for gastroenteritis and other conditions, but the differences were not significant.     

Motilin and infantile colic. A prospective study

Two hundred and nineteen infants, consecutively born, took part in a prospective study of infantile colic from birth to 12 weeks of age. The prevalence of infantile colic in this group was 17.4%. S-motilin was studied in 78 term infants (19 with and 59 without infantile colic) at birth (cord blood), at one day, and at 6 and 12 weeks of age, respectively. Basal motilin levels were raised both in cord blood (p less than 0.01) and in blood from neonates (p less than 0.001) who developed colic as well as in 6 week (p less than 0.05) and in 12-week-old infants with colic (p less than 0.01). Formula-fed infants with colic had higher basal motilin levels than formula-fed controls at 6 and 12 weeks of age (p less than 0.05). Breast-fed infants with colic had higher basal motilin levels than breast-fed controls at 12 weeks of age (p less than 0.05). The raised levels of motilin from the first day of life in infants who develop infantile colic might indicate that the gastrointestinal tract is affected in infants with infantile colic, before any symptoms of colic appear.     

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.     

Clinical study of prolonged jaundice in breast- and bottle-fed babies.

A study of 893 births was undertaken to determine the incidence of prolonged neonatal jaundice. 55% of these babies were breast feeding on discharge from the maternity hospital. Jaundice lasting for 3 weeks or more was found in 12 breast-fed term babies (2-4% of all breast-fed babies), and in no bottle-fed infant. 3 of the jaundiced babies gained weight poorly in the first 3 weeks of life, but after that age failure to thrive was not associated with the prolonged jaundice. The hyperbilirubinaemia, which persisted in 11 infants from between 21 to 80 days (mean 39 days), was due to elevations in both conjugated and unconjugated fractions.     

Clinical and biochemical assessment of a modified evaporated milk for infant feeding

A clinical and biochemical evaluation has been made of a new milk formula, Modified Carnation milk (MCM), based on cows' milk but with the mineral content and concentration of caloric nutrients altered to make it correspond more closely to human milk. MCM produced higher plasma calcium and magnesium concentrations in 6-day-old infants than those produced by unmodified evaporated and dried milks, achieving concentrations closer to those of breast milk. Plasma free amino acid concentrations in MCM-fed infants are nearer breast-fed values than those in unmodified milk-fed infants where higher individual plasma amino acid concentrations persist during the first 3 months. MCM-fed infants had low plasma urea concentrations and lower urine osmolalities at 6 days, 3 weeks, 6 weeks, 3 months, and 6 months than infants fed on the evaporated and dried milks, and similar plasma urea and urine osmolalities to those of breast-fed infants. MCM is likely to be superior to unmodified evaporated and dried milks in preventing convulsions of the hypocalcaemic/hypomagnesaemic/hyperphosphataemic type, and seems less likely to cause hypertonic dehydration. MCM is easily prepared, readily accepted by babies, and appears to be nutritionally adequate for the feeding of term infants.     

Role of prolonged breast feeding in infant growth

The growth of 238 healthy full-term infants was followed under a carefully monitored nutritional protocol during the first year of life. The infants were weaned at different ages either to a proprietary infant milk formula or to a home-prepared cow's milk formula. Solid foods were introduced at 3.5 months of age. The 56 infants who were breast-fed for a period of at least 6 months were compared to infants weaned prior to one month of age to one of the two milk regimens. In the breast-fed infants, the weight, weight-for-height-age, and skinfold thickness were similar to values in the proprietary formula-fed infants but were lower than the corresponding values in the cow's milk-fed infants at 6 months of age and subsequently. By using weight-for-height-age as a criterion, no obesity was found among any of the 238 infants, and only 1.7% were considered to be overweight. The results indicate that present recommendations for infant feeding in Finland--including prolonged breast feeding, the use of proprietary milk formulas after weaning, and later introduction of solid foods--prevent overnutrition.     

Iron and the exclusively breast-fed infant from birth to six months

This study was designed to determine whether normal, full-term, exclusively breast-fed infants develop iron deficiency anemia, as defined by hemoglobin or red blood cell indices more than two standard deviations below the age-specific mean, or depletion of iron stores, as defined by an abnormally low serum ferritin level. Thirty-three breast-fed infants were followed from birth to 6 months. Maternal blood and cord blood at delivery, and venous blood from the infants at 2, 4, and 6 months were analyzed for anemia as defined above. At 6 months of age, the mean hemoglobin concentration of these infants was slightly higher than the normal mean; four of 33 infants (12%) had a mean corpuscular volume greater than 2 SD below the reported normal mean; and two of 33 infants (6%) had a serum ferritin level less than 12 ng protein/ml. These data suggest that the infant who is exclusively breast-fed for the first 6 months of life is not at high risk for the development of iron deficiency anemia or the depletion of iron stores during that time.     

Crying, fussing and colic behaviour in breast- and bottle-fed infants

Persistent infant crying and "colic" have been linked in some studies to feeding, but this association has not been tested in a planned longitudinal study comparing breast- with formula fed babies. We used validated maternal diaries of infant behaviours, kept for three days at both two and six weeks of infant age, in a comparative study of 97 breast- or formula fed babies. The total duration of overall crying rose significantly between 2 and 6 weeks in breast-fed infants and fell in those fed formula. At 6 weeks, breast-fed infants cried an average of almost 40 minutes more per day than formula fed infants; and 31% cried for more than three hours per day, compared with only 12% of the formula fed group. At six weeks, breast-fed infants also slept almost 80 minutes less per day than the formula fed babies. While six weeks is the established peak age for infant crying, those fed formula peaked much earlier and at 2 weeks intense crying/colic behaviour occurred in 43% of formula fed babies and just 16% of those fed by breast. These findings link the timing of the infant crying peak to the mode of feeding. Our data indicate that any regimen designed to reduce crying should commence in the neonatal period in formula fed infants.     

Infant Health and Breast-Feeding During the First 16 Weeks of Life

Infant health and breast feeding during the first 16 weeks of life. The relationship between the method of infant feeding and health during the first sixteen weeks of life was examined in a cohort of 1,210 children.
Totally bottle-fed infants had four times the risk of consulting a medical practitioner for gastrointestinal disturbances when compared with totally breast-fed infants.
Breast-fed infants had significantly less gastrointestinal and respiratory illness irrespective of medical attendance. However, when social background was taken into account, the relationship between breast feeding and respiratory illness became nonsignificant.
The mortality rates and risk of hospitalisation for respiratory infections and gastrointestinal illness were unaffected by the method of feeding.
Although breast feeding remains the optimal form of infant nutrition, the results of this study show that the benefits are marginal in a developed community in terms of illness in early infancy.