By Nicole Avena, PhD
Feeding a baby for the first time is fun and exciting, for all parties involved. Who doesn’t love to see the video of a baby’s face after trying a new food for the first time? However, amid all the excitement, parents often make one of the biggest mistakes they can when it comes to establishing healthy food preferences in a baby’s diet and probably don’t even realize it: they are trying too many different foods too quickly.
Research has shown that regardless of whether infants are breastfed, formula fed, or both, once they transition to solid foods, acceptance of fruits and vegetables increases most when the baby is repeatedly exposed to each one. Most feeding guidelines don’t follow this advice, though. Typically, they suggest trying rice or barley for a few days and then adding a fruit or veggie. Usually, 2 to 3 days of exposure is given before a new food is suggested to be introduced. While 2 to 3 days may be sufficient to alert you to the presence of an allergic reaction, studies show you need more time to establish liking of a food. How much more time? Between 8 and 10 days. That might sound like a lifetime to you (and your baby), but that will give you the best chance of creating a strong preference for these foods (especially vegetables). Remember, when you feed a baby, she needs to actually taste the food in order to create an experience with it. Often, this feeding is messy, as baby spits it out or fusses at new tastes. Studies show that the more days a baby is exposed to a food, the more likely her facial expressions are to change to suggest she likes it, and the more likely moms are to report that they think the baby likes it.
Young children live in a taste world that’s very different from the adult one. Our brains have been biologically programmed such that early in life our sensory systems detect and prefer calorie-and mineral- rich foods that taste sweet or salty, while rejecting the potentially toxic ones that taste bitter (like cruciferous vegetables, such as broccoli). This is because in nature, sweet and salty foods tend to be safe to consume, while bitterness is often a sign that the food has gone bad (think about a fermented piece of fruit that may have fallen from a tree). So there is a biological basis to why kids like candy and don’t like most veggies! Babies naturally prefer sweeter things more than adults do. But we can capitalize on this. Clinical research has shown that school-aged children like vegetables better if they are sweetened. So even though children have been biologically programmed to be leery of bitter foods, their preference for sweet and salt at a young age can actually trump the dislike of bitter tastes. Similar research conducted in babies showed that repeated exposure to green beans and/or peaches increased intake (as I said earlier, 8 to 10 days of exposure is best), but only the babies who ate the peaches right after green beans appeared to like the taste of the green beans more after the 8 days of exposure. It may be that the sweet taste of peaches masked some of the bitterness of the green beans, increasing their palatability and making it easier for the baby to like.
Nicole Avena, PhD, is Assistant Professor of Neuroscience at Mount Sinai School of Medicine and Visiting Professor of Health Psychology at Princeton University. She is the author of several books, including What to Feed Your Baby and Toddler, and What to Eat When You’re Pregnant. The post was adapted from What to Feed Your Baby and Toddler.
