M Giovannini

Lower protein in infant formula is associated with lower weight up to age 2 y: a randomized clinical trial

BACKGROUND Protein intake during infancy was associated with rapid early weight gain and later obesity in observational studies. OBJECTIVE The objective was to test the hypothesis that higher protein intake in infancy leads to more rapid length and weight gain in the first 2 y of life. DESIGN In a multicenter European study, 1138 healthy, formula-fed infants were randomly assigned to receive cow milk-based infant and follow-on formula with lower (1.77 and 2.2 g protein/100 kcal, respectively) or higher (2.9 and 4.4 g protein/100 kcal, respectively) protein contents for the first year. For comparison, 619 exclusively breastfed children were also followed. Weight, length, weight-for-length, and BMI were determined at inclusion and at 3, 6, 12, and 24 mo of age. The primary endpoints were length and weight at 24 mo of age, expressed as length and weight-for-length z scores based on the 2006 World Health Organization growth standards. RESULTS Six hundred thirty-six children in the lower (n = 313) and higher (n = 323) protein formula groups and 298 children in the breastfed group were followed until 24 mo. Length was not different between randomized groups at any time. At 24 mo, the weight-for-length z score of infants in the lower protein formula group was 0.20 (0.06, 0.34) lower than that of the higher protein group and did not differ from that of the breastfed reference group. CONCLUSIONS A higher protein content of infant formula is associated with higher weight in the first 2 y of life but has no effect on length. Lower protein intake in infancy might diminish the later risk of overweight and obesity. This trial was registered at clinicaltrials.gov as NCT00338689.

Can infant feeding choices modulate later obesity risk

Since the concept of lasting programming effects on disease risk in human adults by the action of hormones, metabolites, and neurotransmitters during sensitive periods of early development was proposed >3 decades ago, ample supporting evidence has evolved from epidemiologic and experimental studies and clinical trials. For example, numerous studies have reported programming effects of infant feeding choices on later obesity. Three meta-analyses of observational studies found that obesity risk at school age was reduced by 15-25% with early breastfeeding compared with formula feeding. We proposed that breastfeeding protects against later obesity by reducing the occurrence of high weight gain in infancy and that one causative factor is the lower protein content of human milk compared with most infant formula (the early protein hypothesis). We are testing this hypothesis in the European Childhood Obesity Project, a double-blind, randomized clinical trial that includes >1000 infants in 5 countries (Belgium, Germany, Italy, Poland, and Spain). We randomly assigned healthy infants who were born at term to receive for the first year infant formula and follow-on formula with higher or lower protein contents, respectively. The follow-up data obtained at age 2 y indicate that feeding formula with reduced protein content normalizes early growth relative to a breastfed reference group and the new World Health Organization growth standard, which may furnish a significant long-term protection against later obesity. We conclude that infant feeding practice has a high potential for long-term health effects, and the results obtained should stimulate the review of recommendations and policies for infant formula composition.

Factors associated with initiation and duration of breastfeeding in Italy

To evaluate factors associated with initiation and duration of breastfeeding in Italy, 1601 (73%) respondents among 2192 randomly selected mothers were interviewed within 1 mo of delivery. Mothers who started breastfeeding (85%) were followed‐up for 12 mo. A compliance rate of 100% was obtained. At multiple logistic regression analysis, mother having been breastfed herself (p<0.01), nursing guidance in the maternity ward (p= 0.01) and higher social class (p= 0.03) were positively associated with initiation of breastfeeding. We found that 42%, 19%, 10% and 4% mothers were still breastfeeding at 3, 6, 9 and 12 mo after delivery, respectively. Cox multiple regression analysis showed a negative association between duration of breastfeeding and pacifier use (p<0.01), and a positive association with a higher level of maternal education (p= 0.04). Formula supplementation in the maternity ward (given to 30% of infants) was associated with a shorter duration of exclusive breastfeeding (p = 0.03). Mothers need support with breastfeeding, particularly those from lower social backgrounds and with lower levels of education. Early use of the pacifier should be discouraged.

How much protein is safe

BACKGROUND:Since breastfeeding and human milk seem to prevent, while high dietary proteins in the first 2 y of life seem to promote, later overweight, questions have been raised on the safe levels of proteins in the early years. How much protein (as a percentage of total calorie intake) is safe?METHODS:Revision of available data on the protein content of human milk, protein intake in the first 2 y of life and their association with body mass development.RESULTS:We should move from the figure of 7–8% in the 4-month exclusively breastfed infants up to the maximum acceptable levels of 14% in 12–24-month-old infants. When protein supply represents less than 6% and energy is limited, fully breastfed infants are likely to enter a status of negative nutrient balance. Over the limit of 14% energy from proteins in the 6–24 months period, some mechanisms may begin to operate, leading young children towards an early adiposity rebound and overweight development, beyond any genetic predisposition. Preliminary data seem to indicate a causal role for whole cows milk proteins.CONCLUSION:We suggest maintaining breastfeeding as long as possible, and, in case human milk is insufficient, to introduce infant formulas, appropriate for age, up to 18–24 months, in order to keep protein intakes in the safe range of 8–12% within a diet adequate in energy and balanced as far as macronutrients.

Earlier smoking habits are associated with higher serum lipids and lower milk fat and polyunsaturated fatty acid content in the first 6 months of lactation

Objective: To investigate the relation between maternal smoking habits, plasma lipids and milk fatty acid (FA) content and composition.Design: Breastfeeding mothers who gave birth to healthy, full-term infants were recruited. Mothers were interviewed on smoking habits, being defined smokers (S) when usually smoking at least five cigarettes per day before pregnancy.Setting: Department of Pediatrics, San Paolo Hospital, Milan, Italy.Subjects: In total, 92 mothers: 61 non-S (NS) and 31 S.Interventions: Pooled hindmilk was collected at the first raise of milk (colostrum stage), 1, 3 and 6 months, and total lipid (TL) content and fatty acid (FA) composition were evaluated. Maternal dietary habits were assessed by a food-frequency questionnaire. Two subsamples (16 NS, 6 S) were investigated after delivery and at 3 months for serum lipids and FA status. At 6 months after delivery, the number of mothers still breastfeeding decreased to 30. Variables were compared using nonparametric tests.Results: In smoking mothers serum levels of triglycerides, cholesterol and low-density lipoproteins were higher, while those of high-density lipoproteins were lower. TL content in breast milk was similar in the two groups just after delivery but higher in milk from NS at 1 month. TL content and FA absolute amounts of linoleic, arachidonic, α-linolenic and docosahexaenoic (DHA) acid in breast milk were lower in S vs NS 1 month after delivery. Also 3 months after delivery, the breast milk of smoking mothers contained less DHA than the breast milk of nonsmoking mothers.Conclusions: Maternal cigarette smoking in early pregnancy is associated with higher plasma lipid levels and lower milk TL and DHA content in the first months of lactation.

Dietary macronutrient intake during the first 10 years of life in a cohort of Italian children

Objective: To describe the longitudinal pattern of dietary energy and macronutrient intakes during the first 10 years of life in a sample of healthy Italian children. Patients and Methods: Sixty-one healthy children were followed from birth to 10 years of age. At 1, 5, 8, and 10 years of age, anthropometric measurements were taken and nutritional habits evaluated using a standardized food frequency questionnaire. Results: Compared to the Italian recommended dietary allowances, the childrens diet was high in protein at any age, high in lipids from age 5 onward, and high in calories at 5 years of age. At 1 year, mean (SD) protein, carbohydrate, and lipid intake, expressed as percentage of total energy, was 20% (3%), 48% (7%), and 34% (5%), respectively. Afterward, the corresponding mean value ranged around 14% to 15%, 57% to 60%, and 29% to 32%. The mean glycemic load and overall glycemic index ranged around 143 to 150 and 58 to 59, respectively. A difference between boys and girls was found in the longitudinal pattern for the intake of energy (P < 0.0001) and glycemic load (P < 0.0001). The individual longitudinal dietary pattern varied over time for the intake of total energy (P < 0.0001), any macronutrient (P < 0.0001), and overall glycemic index (P = 0.05). Conclusions: Although the amount of energy intake was in accordance with the Italian recommended dietary allowances, children consumed a high-protein and high-lipid diet. Early and continuous dietary education of children and parents may provide support for adequate nutritional habits throughout their childhood.

Long-chain polyunsaturated fatty acid concentrations in human hindmilk are constant throughout twelve months of lactation.

We assessed the total fat content and fatty acid concentrations in colostrum and throughout a nursing period of 12 months in a group of mothers recruited after delivery of full-term infants. Pooled human milk (hindmilk) was collected from all feedings over 24 hours at the following times: 1st day of nursing (colostrum), and at 1, 3, 6, 9, and 12 months. Total fat was quantified by a microgravimetric method. Fatty acids were analyzed by means of capillary gas chromatography. Comparisons were made with analysis of variance for repeated measures. Ten mothers completed the follow-up 12-month nursing period. We found that the total lipid content of hindmilk (mg/dL) rises more than 3-fold from the colostrum up to the 3rd month, and then more slowly up to the 12th month. Total saturated fatty acids progressively increase and total monounsaturated FA progressively decrease. Among long-chain polyunsaturated fatty acids, we found that the concentrations (mg/dL) of C20:4 and C22:6 remain stable from colostrum up to the 12th month of nursing, while their percentage levels are highest in colostrum and decrease afterwards in association with the increase in total fats. The C18:2n6 and C18:3n3 amounts progressively increase, following the trend of total fats. These data indicate that the secretion of arachidonic acid and docosahexaenoic acid during lactation remains constant, in spite of changes in total fat and in the linoleic acid and alpha-linolenic acid contents of milk.

Monitoring breastfeeding rates in Italy.

Aim: to determine the rates of initiation and duration of breastfeeding in Italy in 1995 and 1999, and to examine the adherence to the ten steps to successful breastfeeding recommended by WHO. Methods: Two cohorts of mothers who delivered healthy infants in November 1995 (n= 2400) or November 1999 (n= 3500) were interviewed by telephone within 4 wk of delivery when their infants were 3 months of age. Type of breastfeeding was classified according to the WHO definitions. Adherence to the WHO ten steps was evaluated. Results: Initiation and duration of breastfeeding increased during the 1995–1999 period (p < 0.0001). The rate of breastfeeding at discharge and when the infants where 3 months of age was 83% and 42% in 1995, and 89% and 66% in 1999. The rate of exclusive/predominant breastfeeding at discharge was higher in 1999 than 1995 (78% vs 72%).

Insulin like growth factor regulation of body mass in breastfed and milk formula fed infants

P. Socha, R. Janas, A. Dobrzanska, B. Koletzko, I. Broekaert, D. Brasseur, A. Sengier, M. Giovannini, C. Agostoni, R. Closa Monasterolo, G. Mendez, EU Childhood Obesity Study Team Childrens Memorial, Health Institute, Warszawa, Poland, Childrens University Hospital, Ludwig Maximilians University, Munich, Germany, Unite de Nutrition, Hopital Universitaire des Enfants Reine Fabiola, Bruxelles, Belgium, Pediatric Department, Ospedale San Paolo, Milano, Italy, Pediatric Unit, University Rovira i Virgili, Tarragona, Spain

Early protein intakes and adiposity: reloaded or downloaded?

It has been hypothesized that feeding human milk through the first year of life may have a protective effect towards a later adiposity development, in contrast with formula feeding. The low protein content of human milk has been hypothesized as a plausible biological hypothesis. Regardless, it is often underscored that feeding human milk is associated with a higher rate of weight gain in the first two months of life.