Fat intake and metabolism in Swedish and Italian infants

The purpose of the study was to compare fat intake and metabolism between two infant populations from Sweden and Italy given breast milk or similar infant formulas, but different weaning foods. Nutrient intake and fat metabolism were studied prospectively from 3-12 mo in 68 Swedish and 46 Italian healthy infants, breastfed or given similar infant formulas in combination with Swedish or Mediterranean weaning foods. Although nutrient intake and fat metabolism were similar at 6 mo, fat intake was lower at 12 mo in the Italian than in the Swedish formula group (p < 0.001). At 6 and 12 mo, higher dietary ratios of monounsaturated to saturated fatty acids (p < 0.01 and p < 0.001, respectively), and monounsaturated to polyunsaturated fatty acids (p < 0.05, p < 0.001) were found in the Italian than in the Swedish formula group. Total cholesterol and apolipoprotein B were lower at 6 mo (p < 0.01) in Italian breastfed infants than in Swedish ones. Lower concentrations at 6 and 12 mo of total cholesterol (p < 0.05, p < 0.05, respectively), apolipoprotein B (p < 0.05, p < 0.01) and triglycerides (p < 0.001, p < 0.01), and of apolipoprotein A1 (p < 0.01) at 12 mo, were found in the Italian formula group than in the Swedish one. In conclusion, plasma total cholesterol, apolipoprotein B and triglycerides were found to be lower in Italian infants than in Swedish infants during the second half of infancy. These findings may partly result from differences in fat compositions between Swedish and Mediterranean weaning diets and in total fat intake in late infancy. Differences in duration of breastfeeding and possibly in breast milk composition may also have influenced our results.     

Plasma lipids and apolipoproteins in breastfed and formula-fed Swedish infants

This study was carried out to compare plasma lipid pattern in breastfed and formula-fed infants and the effects of exchanging breast milk for formula and of introducing weaning foods. Healthy infants, exclusively breastfed at least until 3 mo, were at this age randomly assigned to infant formulas with similar fat composition. Formula was gradually introduced when breastfeeding was discontinued. One group continued to breastfeed beyond 6 mo of age. All infants received the same weaning foods and were studied between 3 and 12 mo of age. Decreased plasma concentrations of total and low-density lipoprotein cholesterol (TC, LDL-C), apolipoprotein B (apo B) and A1 (p < 0.001), and of high-density lipoprotein cholesterol (p < 0.05) were found when breast milk was exchanged for formula before 6 mo. At this age plasma TC, LDL-C and apo B were lower in formula-fed than in breastfed infants (p < 0.001). These plasma lipids then increased (p < 0.01) when the intake of formula decreased and that of weaning foods increased. However, plasma TC and/or LDL-C remained lower at 12 mo in formula-fed than in breastfed infants (p < 0.05). Our results indicate that the plasma lipid profile of infants is highly responsive to the dietary nutrient intake, as indicated by the decrease in plasma lipids and apolipoproteins when breast milk was exchanged for formula and by the increase in these concentrations when the intake of weaning foods gradually increased.     

Iron-fortified and unfortified cow's milk: effects on iron intakes and iron status in young children

Iron intakes and iron status were evaluated in 36 young Swedish children given either iron-fortified or unfortified cow's milk. All children had good iron status and had received breast milk or ironfortified formulae during infancy. Twenty 1-y-old children were randomized to a diet with ironfortified milk (7.0 or 14.9 mg Fe l^-1     

Weaning preterm infants: a randomised controlled trial

OBJECTIVE: To assess the effect on growth and iron status in preterm infants of a specially devised weaning strategy compared with current best practices in infant feeding. The preterm weaning strategy recommended the early onset of weaning and the use of foods with a higher energy and protein content than standard milk formula, and foods that are rich sources of iron and zinc. Subjects and design: In a blinded, controlled study, 68 preterm infants (mean (SD) birth weight 1470 (430) g and mean (SD) gestational age 31.3 (2.9) weeks) were randomised to either the preterm weaning strategy group (n = 37) or a current best practice control group (n = 31), from hospital discharge until 1 year gestation corrected age (GCA). MAIN OUTCOME MEASURES: Weight, supine length, occipitofrontal head circumference, and intakes of energy, protein, and minerals were determined at 0, 6, and 12 months GCA. Levels of haemoglobin, serum iron, and serum ferritin were assayed at 0 and 6 months GCA. RESULTS: Significant positive effects of treatment included: greater increase in standard deviation length scores and length growth velocity; increased intake of energy, protein, and carbohydrate at 6 months GCA and iron at 12 months GCA; increased haemoglobin and serum iron levels at 6 months GCA. CONCLUSIONS: The preterm weaning strategy significantly influenced dietary intakes with consequent beneficial effects on growth in length and iron status. This strategy should be adopted as the basis of feeding guidelines for preterm infants after hospital discharge.     

Iron balance and iron nutrition in infancy

At birth, the total body iron content is approximately 75 mg/kg, twice that of an adult man in relation to weight. During the first 6 mo of life, total iron body content increases slightly and exclusive breastfeeding is sufficient to maintain an optimal iron balance. Thereafter, iron body content substantially increases and the infant becomes critically dependent on dietary iron, provided by complementary foods. Numerous factors may contribute to nutritional iron deficiency in infancy, the most important being low body iron content at birth, blood loss, high postnatal growth rate, and a low amount and/or bioavailability of dietary iron. We have documented that the prevalence of iron deficiency declined in Italy as iron nutrition improved and that early feeding on fresh cow's milk is the single most important determinant of iron deficiency in infancy. Healthy full-term infants should maintain optimal iron balance by consuming a good diet, which can be summarized as follows: breastfeeding should be continued exclusively for at least 5 mo and then together with complementary foods containing highly bioavailable iron; infants who are not breastfed or are partially breastfed should receive an iron-fortified formula, containing between 4.0 and 8.0mg/L iron, from birth to 12 mo of age; fresh cow's milk should be avoided before 12 mo of age.     

Iron balance and iron nutrition in infancy

At birth, the total body iron content is approximately 75 mg/kg, twice that of an adult man in relation to weight. During the first 6 mo of life, total iron body content increases slightly and exclusive breastfeeding is sufficient to maintain an optimal iron balance. Thereafter, iron body content substantially increases and the infant becomes critically dependent on dietary iron, provided by complementary foods. Numerous factors may contribute to nutritional iron deficiency in infancy, the most important being low body iron content at birth, blood loss, high postnatal growth rate, and a low amount and/or bioavailability of dietary iron. We have documented that the prevalence of iron deficiency declined in Italy as iron nutrition improved and that early feeding on fresh cow's milk is the single most important determinant of iron deficiency in infancy. Healthy full-term infants should maintain optimal iron balance by consuming a good diet, which can be summarized as follows: breastfeeding should be continued exclusively for at least 5 mo and then together with complementary foods containing highly bioavailable iron; infants who are not breastfed or are partially breastfed should receive an iron-fortified formula, containing between 4.0 and 8.0 mg/L iron, from birth to 12 mo of age; fresh cow's milk should be avoided before 12 mo of age.     

Evaluation of full-term infants fed an evaporated milk formula

The objective of this prospective, cohort study was to compare the nutritional status of full-term infants who were fed human milk (BF, n = 29). formula (FF, n = 30) or evaporated milk formulae (EM, n = 30) for at least 3 months. Infants were seen at enrollment, 3 and 6 months, at which times a blood sample, diet record and anthropometric data were collected. Infants in the EM group received solids earlier (12 ± 5 weeks) than did FF infants (15 ± 4 weeks), and both were earlier than BF infants (19 ± 4 weeks). Only 26% of the EM fed group received iron supplements as ferrous sulphate drops. Seven BF, 12 FF and 20 EM had abnormal ferritin values (<10ngml^-1) at 6 months. Copper intake was lower in the EM infants at 3 and 6 months. However, plasma copper and erythrocyte copper zinc superoxide dismutase (ZnCuSOD) levels did not differ between groups. Selenium intake was lower in the EM group (5 ± 1 and 10 ± 5 μg d^-1; 3 and 6 months) than in the FF infants (13 ± 4 and 19 ± 7 μgd^-1; 3 and 6 months). Erythrocyte SeGHSPx levels in EM infants were lower at 6 months (EM, 33.2 ± 3.4; FF, 35.2 ± 3.9; BF, 36.1 ± S.SmUmgHb^-1). Thiamin intake (0.99 ± 0.08 and 1.24 ± 0.32; 3 and 6 months, mg 1000 kcal^-1) was higher in the FF group than in EM infants (0.38 ± 0.39 and 0.66 ± 0.38; 3 and 6 months). There were more (13%) abnormal thiamin assays in the EM group at 6 months than in the BF and FF infants (0%). In conclusion, infants fed evaporated milk formula receive adequate copper but may not receive enough thiamin or selenium. Unless supplemented from birth with medicinal iron, intakes of iron will be inadequate.     

Are weaning foods causing impaired iron and zinc status in 1-year-old Swedish infants? A cohort study

We analysed whether 12-month-old Swedish infants who have been fed iron-fortified and relatively zinc-rich foods, according to current recommendations, have adequate iron and zinc status. A cohort of 76 healthy, full term Swedish infants was followed regarding feeding habits and growth from birth to 12 months of age, when haemoglobin, iron and zinc status were evaluated. Twenty-six percent of the infants had low (<12μg/l) s-ferritin values, indicative of iron depletion, and 36% of the infants had low s-zinc concentrations (<10.7/μmol/l). Only two infants had both low haemoglobin and low s-ferritin values. s-Zinc and s-iron were positively correlated, and s-zinc and s-transferrin receptor values were negatively correlated. Lower birthweight was associated with lower s-ferritin levels at 12 months in boys, and with increased s-transferrin receptor values in girls. Feeding habits during infancy were relatively homogenous, dominated by breastfeeding, iron-fortified milk- and cereal-based follow-on formula. No clear association between feeding pattern and iron and zinc status was found. The results indicate that in a group of healthy, well growing 12-month-old Swedish infants one-quarter is iron-depleted, although iron deficiency anaemiau is rare, and one-third may be zinc-depleted. The high cereal intake of Swedish infants from 6 months of age may have limited the bioavailability of both iron and zinc from the diet.     

Maternal BMI and serum leptin concentration of infants in the first year of life

Aim: To evaluate the relationship between serum leptin concentration in infants and infant and maternal BMI. Methods: 75 healthy term infants aged 0-12 mo, 51 exclusively breastfed (BF) for at least 4 mo and 24 formula fed (FF), were included in a cross-sectional study. Weight, length and cranial circumference of infants and their mothers were measured, body mass index (BMI) was calculated using the formula weight (kg)/height (m)² and infant serum leptin concentration was determined. Results: A significant positive correlation between infant serum leptin concentration and maternal BMI was observed in BF infants (r = 0.389, p = 0.005), confirmed in a multiple regression model adjusted for infant age and infant BMI (β = 0.065, p = 0.006), but not in FF infants. As regards the first 4 mo of life, we have already observed a positive correlation between infant serum leptin concentration and maternal BMI in BF infants (β = 0.113, p = 0.005), but not in FF infants.

Conclusion: In BF infants, serum leptin concentration correlates positively with maternal BMI. Higher maternal BMI values might increase leptin levels in breast milk, and maternal adiposity could be involved in infant energy balance.     

Type of milk feeding affects hematological parameters and serum lipid profile in Japanese infants

Background: Type and volume of infant feeding determines infant growth, hematological parameters, and serum lipids. Methods: Study subjects consisted of 103 infants who were born vaginally at term, with birthweight >2200 g. Milk feeding amount, type, and anthropometry were measured at 1 and 6 months. Hematological tests and serum lipid profile were assessed at 1 and 6 months. Thirty‐four infants were breast‐fed and 36 were formula‐fed at 6 months. Results: Breast‐fed infants demonstrated similar growth patterns compared with partially breast‐fed or formula‐fed infants, despite the lower milk intake. Infants with higher breast milk intake at 6 months, however, tended to have lower hemoglobin levels. In contrast, higher formula intake at 6 months was related to lower serum total cholesterol. Conclusions: Japanese breast‐fed infants were more likely to be anemic at 6 months, while formula‐fed infants were likely to have low serum lipid levels. Iron‐fortified infant foods may be useful to prevent anemia in breast‐fed infants. Fat quality of infant formulas should be improved to enhance lipid status of formula‐fed infants.     

Feeding preterm infants after hospital discharge: effect of diet on body composition.

Our purpose in this study was to examine whole body composition, using dual energy x-ray absorptiometry (DEXA) during dietary intervention in preterm infants (< or = 1750 g birthweight, < or = 34 wk gestation). At discharge, infants were randomized to be fed either a preterm infant formula (discharge-6 mo; group A) or a term formula (discharge-6 mo; group B), or the preterm formula (discharge-term) and the term formula (term-6 mo; group C). Nutrient intake was measured between each clinic visit. To measure body composition, DEXA was used at discharge, term, 12 wk, 6 mo, and 12 mo corrected age. The data were analyzed by ANOVA. At discharge, no differences were noted in patient characteristics between groups A, B, and C. Although energy intakes were similar, protein and mineral intakes differed between groups (A > C > B; p < 0.0001). During the study, weight gain and LM gain were greater in group A than B. At 12 mo, weight, LM, FM, and BMM but not % FM or BMD were greater in group A than B. However, the effects of diet were confined to boys, with no lasting effects seen in girls. In summary, therefore, DEXA was precise enough to detect differences in whole body composition during dietary intervention. Increased weight gain primarily reflected an increase in LM and is consistent with the idea that the preterm formula more closely met protein and/or protein-energy needs in rapidly growing preterm male infants.     

Long-chain polyunsaturated fatty acids in human milk and brain growth during early infancy

Long-chain polyunsaturated fatty acids are essential for growth and development, and their crucial role in the development of the central nervous system and in retinal function has been the subject of many studies. As the balance between n-6 and n-3 fatty acids has to be optimal, their concentrations in the milk given to infants who are exclusively breastfed is of major importance. In this study, the composition of fatty acids in mothers' milk and the growth rate of the infant brain were analysed. Nineteen mother-term infant pairs from Stockholm, Sweden, were studied from birth to 1 mo and 3 mo of age, during which time the infants were breastfed exclusively. The dietary intake of the mothers was calculated and found to concur with the recommended daily dietary allowances of Swedish lactating women as regards energy, protein, fat and carbohydrates. The amounts of linoleic acid and alpha-linolenic acid in the diet were similar to those reported for European and North American women. The ratio between arachidonic acid (AA) and docosahexaenoic acid (DHA) in the milk from Swedish mothers is approximately the same as in the brain of infants, and was found to be positively correlated with the rate of gain of the occipito-frontal head circumference and of the calculated brain weight at 1 mo (p < 0.01) and 3 mo (p < 0.01) of age, respectively. However, further studies are needed to establish the exact requirements of AA and DHA for optimal growth and development during early infancy in exclusively breastfed infants.     

Langfristige Prägung der Gesundheit durch die Säuglingsernährung

The early nutrition from conception to early childhood has imprinting or programming effects on later health and disease risks. Rapid weight gain in fetal life and early childhood increases the risk of later obesity, diabetes and other non-communicable diseases (NCD). In observational cohort studies rapid weight gain from birth to 2 years old was associated with an increased risk of obesity up to adulthood. Breastfeeding is associated with less rapid weight gain in infancy than conventional infant formula nutrition. Several meta-analyses of observational studies found that breastfeeding was associated with an approximately 12–24?% reduction in the risk of obesity in later life. We investigated the early protein hypothesis, which proposes that a high protein intake in infancy leads to increased concentrations of insulinogenic amino acids, the growth factors insulin and insulin-like growth factor-1 (IGF-1) as well as greater weight gain and later obesity. The hypothesis was tested in a double blind randomized clinical trial involving 1678 term infants who received conventional infant and follow-on formulae with higher protein content or with reduced protein content during the first year of life. The reduced protein diet led to significantly reduced body weight, weight-for-length and body mass index (BMI) up to the age of 2 years and to a 2.4–2.9-fold reduction of obesity at 6 years old compared to conventional bottle feeding formulae. We concluded that infant feeding has powerful long-term programming effects, with very large effect sizes on obesity in early school age. Breastfeeding should be actively promoted, protected and supported. Infants not exclusively breastfed should receive infant formulae with reduced protein content. Unmodified cows’ milk contains three times as much protein as human milk and should be avoided as a drink in infancy.     

Protein Intake during Weaning

ABSTRACT. Metabolic responses to different feeding regimens during the weaning period have not previously been studied. In this study 30 healthy infants aged 4–6 months were divided into three feeding regimens with 10 infants in each. The regimens were: Human milk (HM-group), formula F₁ with 1.9g protein/100 ml (F₁-group) or formula F² with 2.7 g protein/100 ml (F₂-group). All infants received the same supplementary food and were fed ad libitum. Concentrations of serum urea were significantly higher ( p <0.001) in the formula groups as compared to the breast-fed infants throughout the entire study period. Serum albumin concentrations were within normal limits in the breast-fed infants indicating adequate protein nutritional status. There were no differences in the concentrations of creatinine and total nitrogen in urine between the artificially fed and the breast-fed infants at the beginning of the study (4 months), but at 6 months these concentrations were significantly higher in the formula-fed infants ( p <0.001). The results suggest that formulas now in common use during weaning provide amounts of protein which produce metabolic manifestations implying excessive protein intakes.     

Breastfeeding among Turkish mothers living in suburbs of Istanbul and Stockholm--a comparison

The infant feeding pattern among 96 Turkish mothers living in a suburb of Istanbul and 30 living in a suburb of Stockholm, both with working class characteristics, was determined. The duration of breastfeeding among the Turkish immigrant group living in the Stockholm suburb was significantly reduced compared with the group with a similar social background but living in a native urban area. Infant feeding pattern among the Turkish immigrant mothers was more similar to that of Swedish populations. Attitudes to breastfeeding among the immigrant group had changed. Early weaning, reliance on commercially available infant foods and bottle feeding characterized their infant feeding practices. The majority of the infants of this group showed a tendency to overweight.     

Maternal consumption of dairy products during pregnancy and lactation, and the development of cow's milk antibodies in the offspring

OBJECTIVE: To assess whether the maternal consumption of milk and milk products affects development of cow's milk (CM) antibodies in infants. DESIGN: A randomized pilot trial using food frequency questionnaires (mothers) and food records (infants). SETTING: Families with a newborn infant with increased HLA-DQB1-conferred risk of type 1 diabetes and at least one first-degree relative affected by type 1 diabetes from 16 hospitals in Finland between April 1995 and November 1997. Subjects and intervention: Infants randomized to receive a hydrolysed formula when breast milk was not available during their first 6-8 mo (n=112). Of these, 13 dropped out by the age of 3 mo and two were excluded due to incomplete CM antibody data. RESULTS: Maternal milk protein intake from cheese during pregnancy was inversely related to IgA-class antibody titres to beta-lactoglobulin (BLG) and casein (CAS) at 3 mo, and to IgA antibody titres to BLG at 6 mo. Maternal consumption of raw milk products during lactation was positively related to the development of IgA antibody titres to CAS at 6 mo, and inversely correlated to IgG antibody titres to bovine serum albumin (BSA) and IgA antibody titres to CAS at 2 y. Maternal cheese consumption was inversely related to the IgG antibody titres to CM formula and CAS and to the IgA antibody titres to CAS in early infancy. CONCLUSIONS: Few associations were established between maternal CM protein intake and CM protein antibody levels in the infants. The milk and milk products taken by the mother differed in their impact on the emerging CM antibody response in the offspring.     

Growth patterns of breast fed and formula fed infants in the first 12 months of life: an Italian study.

AIM: To compare the growth patterns of breast fed and formula fed Italian infants in the first 12 months of life using World Health Organisation (WHO) reference data. METHODS: The growth patterns of 73 breast fed infants (36 male, 37 female) and 65 formula fed infants (35 male, 30 female) were compared. Solid foods were introduced with the same weaning schedules from the 5th month in both groups. The weight for age (WA), length for age (LA), and weight for length (WL) z scores (National Center for Health Statistics-WHO data) were calculated at birth, 1, 2, 3, 4, 6, 9, and 12 months. RESULTS: Breast fed infants had the highest z scores (WA, WL) at birth. Breast fed groups had significantly higher growth indices at 1 month (WA, LA), 2 months (WA) and 3 months (WA, LA) of age. Compared to breast fed groups, formula fed infants showed significantly higher WA z score changes in the 1-2, 2-3, 3-4, and 4-6 month intervals. LA z score changes were higher for breast fed infants at 0-1 month and for the formula fed infants at 4-6 months. In the 6-12 month interval growth indices progressively increased for the formula fed infants and declined for infants breast fed for longer (12 months). The 0-12 month changes in WA, LA, and WL z scores were positive for formula fed infants and negative for the 12 month breast fed group. Nevertheless, the 12 month breast fed group showed an absolute WA z score just below 0 (mean (SEM) -0.04 (0.26)) at 12 months. CONCLUSION: The growth pattern of breast fed and formula fed Italian infants differs in the first 12 months of life. This questions the validity of current reference values for monitoring the growth of breast fed infants. Growth indices in breast fed groups, high at birth and closer than expected to the reference at 12 months, may reflect differences in genetic factors, intrauterine conditions, or both.     

Breastfeeding among Turkish Mothers Living in Suburbs of Istanbul and Stockholm–A Comparison

ABSTRACT. The infant feeding pattern among 96 Turkish mothers living in a suburb of Istanbul and 30 living in a suburb of Stockholm, both with working class characteristics, was determined. The duration of breastfeeding among the Turkish immigrant group living in the Stockholm suburb was significantly reduced compared with the group with a similar social background but living in a native urban area. Infant feeding pattern among the Turkish immigrant mothers was more similar to that of Swedish populations. Attitudes to breastfeeding among the immigrant group had changed. Early weaning, reliance on commercially available infant foods and bottle feeding characterized their infant feeding practices. The majority of the infants of this group showed a tendency to overweight.     

Infant feeding in the second 6 months of life related to iron status: an observational study.

OBJECTIVE: To investigate the relationship between iron status in infancy and type of milk and weaning solids consumed. DESIGN: An observational cohort study. SETTING: 928 term infants from the Avon Longitudinal Study of Parents and Children in 1993-94. METHODS: Haemoglobin and ferritin concentrations at 8 and 12 months were assessed in relation to type and quantity of milk intake at 8 months. RESULTS: By WHO criteria, 22.7% of the infants were anaemic at 8 months and 18.1% at 12 months. More breast--than formula-fed infants were anaemic at 8 and 12 months. Cows' milk as the main drink was associated with increased anaemia at 12 months and low ferritin at 8 and 12 months. No association was found between any nutrients and haemoglobin concentrations. Protein and non-haem iron intakes were positively associated with ferritin concentrations and calcium intake negatively. This effect was more marked in infants being fed cows' milk. More than 25% of infants in the breast milk and cows' milk groups and 41% of infants having >6 breast feeds per day had iron intakes below the lower reference nutrient intake. Feeding cows' milk or formula above 600 ml or >6 breast feeds per day was associated with lower intakes of solids. CONCLUSIONS: Both breast and cows' milk feeding were associated with higher levels of anaemia. Satisfactory iron intake from solids in later infancy is more likely if formula intake is <600 ml per day and breast feeds are limited to <6 feeds per day. Cows' milk should be strongly discouraged as a main drink before 12 months.     

Nutrient intake and growth performance of older infants fed human milk

STUDY OBJECTIVE: To determine whether the ad libitum addition of solid foods to the diet of exclusively human milk-fed infants will increase energy intake and reverse the decline in weight-for-age percentiles observed during the exclusive breast-feeding period. DESIGN: Weekly or biweekly measures of growth were made longitudinally on a cohort of infants from birth to 36 weeks of age, and monthly measures of nutrient intake were made from 16 weeks of age until 10 weeks after solid foods were introduced into the diet. SUBJECTS: Volunteer mother-infant pairs from middle and upper income groups who met entry criteria, including the intention to breast-feed exclusively for at least for 16 weeks; 58 pairs entered and 45 pairs completed the study. INTERVENTION: Solid foods were introduced at a time determined by the mother and the pediatrician; solid foods from controlled lot numbers were provided for each infant. MEASUREMENTS AND MAIN RESULTS: After solid foods were added, daily human milk intake declined at a rate of 77 gm/mo (p less than 0.001). Milk composition did not change during the observation period. Daily total energy intake increased 29 kcal/mo, but no changes were noted in energy intake when consumption was normalized for body weight. Weight (National Center for Health Statistics percentiles) at 28 weeks was 13 percentiles lower than that at birth, and length at 28 weeks was 1 percentile lower than at week 1. Weight and length percentiles at 28 weeks, when compared with peak values at 8 weeks, had dropped 19 and 14 percentiles, respectively. CONCLUSIONS: Energy intake of human milk-fed infants did not increase after solid foods were added to their diet but was maintained at approximately 20% below recommended levels. Energy intake appeared to reflect infant demands. These data suggest that the recommendations for the energy requirements of infancy should be reevaluated. The growth pattern of exclusively breast-fed infants differs from that of the National Center for Health Statistics reference population. These observations raise questions about the adaptive response of human milk-fed infants to different levels of energy intake and about the estimations of energy requirements based on the sum of basal metabolism, activity, growth, and diet-induced thermogenesis.