Does Baby Know Best?

Wei Perng, PhD

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The “rise again” of baby-led weaning. For the last century or so, parents have been advised to introduce solid foods to their infants – usually starting sometime between 4 and 6 months of age – by spoon-feeding specially prepared foods. The meals start out as smooth purees and, as the infant gets older, progress in texture, flavor, and variety until 1 year of age, when the baby is able to eat what the rest of the family is eating. Spoon-feeding gives the parent control over what and how much the baby is eating. However, in the last decade or so, baby-led weaning has grown in popularity. Instead of giving the infant special foods, they are allowed to feed themselves finger-sized portions of family foods. (Of course, one should keep in mind that parents have likely been practicing baby-led weaning for millenia, prior to modern food processing technologies). In addition to promoting an inclusive eating environment wherein the baby joins the family at mealtime, baby-led weaning is purported to expose infants to a wide variety of foods, thereby decreasing risk of food allergies, and promote development of fine motor skills (discussed in book Rapley G and Murkett T. Baby-led weaning: helping your baby to love good food. Random House 2008). Of particular interest to me is the hypothesis that baby-led weaning reduces future risk of obesity. But how?

Baby-led weaning and obesity risk. The idea is that by allowing infants choose what and how much to eat, they develop healthy eating behaviors and are better able to self-regulate food intake, both of which are associated with lower risk of obesity later in life. However, does the scientific evidence pan out? Not exactly. While observational studies (see for example, Townsend et al.) reported protective effects of baby-led weaning against future obesity, it is difficult to fully account for confounding variables (e.g., socioeconomic status, family environment, life style characteristics, dietary intake) that could be driving study findings. This suspicion became particularly evident when Taylor et al. reported findings from the first randomized controlled trial (RCT) of the effect of weaning practices on future adiposity. In this RCT, mother-infant pairs were randomly assigned to a baby-led weaning or a spoon-feeding group for the first two years of the infant’s life. At 12 and 24 months, the investigators measured the child’s body mass index (BMI), and found no difference between the two groups at either age. Because RCTs minimize confounding by randomizing participants to an intervention vs. control arm, thereby reducing the possibility of differences between the two groups, this study design enables researchers to quantify an actual causal effect of an intervention. Such findings call into question those of previous observational studies and emphasize the need for additional research to explore the impact of baby-led weaning beyond infancy.

So, what’s a health-conscious mom to do? As is the case with most health trends and fads, it’s important to keep in mind the multifactorial nature of chronic diseases. For example, whether you choose to introduce your infant to solids by spoon-feeding, baby-led weaning, or a combination of the two, keep in mind the importance of introducing healthy foods, like fresh vegetables, whole grains, and lean proteins, and limiting excess oils, salt, and sugar. There is also evidence that infants model eating behaviors after their caretakers, so practicing healthy eating habits yourself is always a good idea. Additionally, staying attuned to your baby’s satiety cues can prevent overfeeding and promote self-regulation, even when spoon-feeding.  For me personally, I enjoy baby-led weaning because it makes the meal preparation process easier. Last night, I handed my 10-month old a small portion of chicken and asparagus, watched him poke and prod at it until he finally put it into his toothless mouth. During clean-up, I found the majority of his meal on the ground and I thought, “Well, of course baby-led weaning is associated with lower risk of obesity… they’re not actually swallowing anything!”