New findings from the Monell Center reveal that weight gain of formula-fed infants is influenced by the type of formula the infant is consuming. The findings have implications related to the infant’s risk for the development of obesity, diabetes and other diseases later in life. “Events early in life have long-term consequences on health and one of the most significant influences is early growth rate,” said study lead author Julie Mennella, Ph.D., a developmental psychobiologist at Monell. “We already know that formula-fed babies gain more weight than breast-fed babies. But we didn’t know whether this was true for all types of formula.”
While most infant formulas are cow’s milk-based, other choices include soy-based and protein hydrolysate-based formulas. Protein hydrolysate formulas contain pre-digested proteins and typically are fed to infants who cannot tolerate the intact proteins in other formulas. In adults, pre-digested proteins are believed to act in the intestine to initiate the end of a meal, thus leading to smaller meals and intake of fewer calories. Based on this, the authors hypothesized that infants who were feeding protein hydrolysate formulas would eat less and have an altered growth pattern relative to infants feeding cow’s milk-based formula.
In the study, published online in the journal Pediatrics, infants whose parents had already decided to bottle-feed were randomly assigned at two weeks of age to feed either a cow’s milk-based formula (35 infants) or a protein hydrolysate formula (24 infants) for seven months. Both formulas contained the same amount of calories, but the hydrolysate formula had more protein, including greater amounts of small peptides and free amino acids. Infants were weighed once each month in the laboratory, where they also were videotaped consuming a meal of the assigned formula. The meal continued until the infant signaled that s/he was full.
Over the seven months of the study, the protein hydrolysate infants gained weight at a slower rate than infants fed cow milk formula. Linear growth, or length, did not differ between the two groups, demonstrating that the differences in growth were specifically attributable to weight. “All formulas are not alike,” said Mennella. “These two formulas have the same amount of calories, but differ considerably in terms of how they influence infant growth.”
When the data were compared to national norms for breast-fed infants, the rate of weight gain of protein hydrolysate infants was comparable to the breast milk standards; in contrast, infants fed cow’s milk formula gained weight at a greater rate than the same breast milk standards. Analysis of the laboratory meal revealed the infants fed the protein hydrolysate formula consumed less formula during the meal. “One of the reasons the protein hydrolysate infants had similar growth patterns to breast-fed infants, who are the gold standard, is that they consumed less formula during a feed as compared to infants fed cow’s milk formula” said Mennella. “The next question to ask is: Why do infants on cow’s milk formula overfeed?”
The findings highlight the need to understand the long-term influences of infant formula composition on feeding behavior, growth, and metabolic health. Future studies will utilize measures of energy metabolism and expenditure to examine how the individual formulas influence growth, and how each differs from breastfeeding. Also contributing to the study, which was funded by the National Institute of Child Health and Human Development, were Monell scientists Gary Beauchamp and Alison Ventura.
Mothers who did not breastfeed their children have significantly higher rates of type 2 diabetes later in life than moms who breastfed, report University of Pittsburgh researchers in a study published in the September issue of the American Journal of Medicine.
“We have seen dramatic increases in the prevalence of type 2 diabetes over the last century,” said Eleanor Bimla Schwarz, MD, MS, assistant professor of medicine, epidemiology, and obstetrics, gynecology and reproductive sciences at the University of Pittsburgh. She also has a secondary appointment in epidemiology at the GSPH. “Diet and exercise are widely known to impact the risk of type 2 diabetes, but few people realize that breastfeeding also reduces mothers’ risk of developing the disease later in life by decreasing maternal belly fat.”
The study included 2,233 women between the ages of 40 and 78. Overall, 56 percent of mothers reported they had breastfed an infant for at least one month. Twenty-seven percent of mothers who did not breastfeed developed type 2 diabetes and were almost twice as likely to develop the disease as women who had breastfed or never given birth. In contrast, mothers who breastfed all of their children were no more likely to develop diabetes than women who never gave birth. These long-term differences were notable even after considering age, race, physical activity and tobacco and alcohol use.
“Our study provides another good reason to encourage women to breastfeed their infants, at least for the infant’s first month of life,” said Schwarz. “Clinicians need to consider women’s pregnancy and lactation history when advising women about their risk for developing type 2 diabetes.”
Schwarz also is an assistant investigator at the Magee-Womens Research Institute. Co-authors of the study include Jeanette Brown, MD, Jennifer M. Creasman, MPH, and David Thom, MD, PhD, University of California, San Francisco; Alison Stuebe, MD, MSc, University of North Carolina School of Medicine; Candace K. McClure, PhD, University of Pittsburgh; and Stephen K. Van Den Eeden, PhD, Kaiser Permanente, CA.
The research was funded by grants from the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases and the National Institute of Child Health and Development.
In the survey, commissioned by Act Against Allergy, further impact on family life was revealed. As a direct result of having a child with CMA, half (49%) the respondents have missed work, over a third (38%) have argued with their partner and 39% said the lives of other children in the family have also been disrupted.1
These findings were no surprise to Natalie Hammond, from Hertfordshire, UK, whose son Joe was diagnosed with CMA when he was six months old. Joe was initially misdiagnosed and even underwent surgery for a twisted bowel before doctors finally discovered that CMA was the cause of his illness. Mrs. Hammond said: “It was heartbreaking and frightening seeing Joe so sick – he would vomit and had blood in his stools. We felt utterly powerless, and couldn't believe a simple food like milk could do this. It took a long time to get over this terrifying and stressful experience.”
Cows' milk is one of the European Union's 'big eight' allergy-inducing foods alongside gluten, eggs, fish, peanuts, soya, treenuts and shellfish. More serious than lactose intolerance, a true milk allergy presents in one or more of three organ systems:
– Gastrointestinal (vomiting, diarrhoea, abdominal cramps, bloating) – affecting 50-60% of those with CMA
– Skin (rashes, including eczema and atopic dermatitis) – 50-70%
– Respiratory (wheeze, cough, runny nose) – 20-30%3
For further information on cows' milk allergy, see: www.actagainstallergy.com