This new research suggests that a healthy diet while pregnant and breastfeeding is more important than ever.
Lots of women up the healthy-eating ante during pregnancy, once their bodies become responsible for nourishing a growing baby. Same goes for breastfeeding moms; diet is known to impact breast milk, and experts are still revealing exactly how.
Researchers just confirmed that fructose—a sugar found in fruit, processed food, and soda, and not a natural component of breast milk—can be passed from mother to child during breastfeeding, according to a new study of 25 mothers and infants published in the journal Nutrients.
Why that matters: Exposing infants and kids to high amounts of sugar during development can increase lifelong risk for obesity, diabetes, fatty liver disease, and heart disease, as well as create problems with cognitive development and learning, as lead author Michael Goran, Ph.D., founding director of the Childhood Obesity Research Center at the Keck School of Medicine said in a release. The researchers found that even a tiny amount of fuctose—the weight of a grain of rice in a full day's serving of breast milk—is associated with increased body weight, muscle, and bone mineral content in babies.
Because the first year of life is a critical development period for the metabolic system (among everything else), researchers believe even tiny amounts of fructose may have negative effects on infant metabolism; fructose could lead pre-fat storage cells to become fat cells, which increases the likelihood that your baby could one day become overweight or obese.
ICYMI, fructose isn't great for adults either; it's been linked to weight gain and can mess with your blood's insulin and triglyceride levels in ways that may increase your diabetes and heart disease risk. While it's found in fruits (here's a breakdown of how much sugar is in some of your favorites), that doesn't mean you should swear off your daily banana and berries. The fructose found in whole fruits isn't a problem because it's generally pretty low and comes with digestion-slowing fiber, according to Manabu Nakamura, Ph.D., an associate professor of nutrition at the University of Illinois at Urbana–Champaign, as we reported here. The main culprit for fructose consumption is soda and other sugary drinks, as well as processed foods loaded with table sugar or high-fructose corn syrup.
One thing the researchers didn't look at: the mother's dietary habits. So it's possible that these women all had diets super high in fructose, and that's why so much "secondhand sugar" was passed along. (Here's what you need to know about the different types of sugar and how they affect your health.)
If you're a new mom don't freak out and drop the apple you were munching on; for one, this was a small prelim study, so there's still a lot for researchers to learn about the link between maternal diet, fructose, and baby health. And even with this new information about "secondhand sugar," breastfeeding is still the ideal form of infant nutrition, and mothers should continue to do so for as long as possible or up to one year, according to Tanya Alderete, Ph.D., coauthor of the study and a postdoctoral research scholar at the Keck School of Medicine. (Breastfeeding has a ton of perks.)
To stay safe, Goran recommends dialing down the sugar while pregnant or breastfeeding and carefully choosing infant formula, baby foods, and snacks without added sugars or sweeteners. (Try these tips for cutting your sugar intake the right way.)