Researchers say that sugar can be passed “secondhand” from mother to their infant by breast milk — and even the tiniest amount of fructose could affect the baby.
The new study by the University of Southern California found that a 1-month-old consuming the amount of fructose equivalent to the weight of a grain of rice (10 milligrams) in a full day’s serving of breast milk can be linked to increased body weight as well as muscle and bone mineral content.
Fructose is not naturally found in breast milk and what researchers call the “secondhand sugar” gets to the breast milk through the mother’s diet. Fructose makes its way into our diets by fruit, processed foods and beverages like Frappuccinos or energy drinks, even cranberry juice cocktails, according to a release on the university’s website. It’s not clear if the mothers consumed fructose-rich foods and drinks, as the study did not analyze their dietary data.
The “healthy” kind of sugars that are natural in breast milk are lactose, and researchers say that helps infants grow and develop, as opposed to fructose, which if exposed to children in high amounts during growth can lead to problems with development. High amounts of fructose in infants can also increase the risk for obesity, diabetes, fatty liver disease and heart disease throughout life, according to the release.
“Lactose is the main source of carbohydrate energy and breast milk is very beneficial, but it’s possible that you can lose some of that beneficial effect depending on maternal diet and how that may affect the composition of breast milk,” said Michael Goran, lead author of the study, in the release. “Other studies have shown that fructose and artificial sweeteners are particularly damaging during critical periods of growth and development in children. We are beginning to see that any amount of fructose in breast milk is risky.”
What the Study Found
Researchers studied 25 mothers who fed their infants breast milk, had less than 8 ounces of formula a week and no solid foods. Samples of the breast milk were taken when the babies were 1 month and 6 months old. The babies had their fat mass, muscle mass and bone mass tested.
“A single microgram of fructose per milliliter of breast milk — that’s 1,000 times lower than the amount of lactose found in breast milk — is associated with a 5 to 10 percent increase in body weight and body fat for infants at six months of age,” according to the release.
The study also showed the importance of the infant’s diet for the body’s metabolic system.
Researchers said fructose could, “coach pre-fat storage cells to become fat cells, raising the baby’s risk of one day becoming overweight or obese.”
What’s the Healthiest Option for Baby?
Even with the chance of “secondhand sugar,” researchers said breast milk is still considered “the gold standard diet for babies,” and that mothers should continue to breast feed for as long as possible or up to one year.
So what should you do to make sure your baby isn’t consuming too much “second hand sugar?”
“New moms can prevent passing secondhand sugars to their children by eating and drinking less sugars while pregnant or breastfeeding,” Goran said. “Caregivers can shield babies and children from harmful effects of sugars by carefully choosing infant formula, baby foods and snacks without added sugars or sweeteners.”
The study brings to light how fructose can affect infant metabolism, giving another factor for mothers to consider when choosing formula or breastfeeding for their infants.
“Early life is a period of rapid development and early nutrition is strongly linked to long-term health outcomes,” co-author of the study Tanya Aldere said in the release. “We know that the decision to breastfeed or bottle feed may have impacts on later health. Results from this work suggest that the composition of breast milk may be another important factor to consider in regard to infant health.”
