Study Finds Timing of Solid Foods Affects Later Life Obesity
Related Materials
A study in the February 2011 edition of Pediatrics titled, “Timing of Solid Food Introduction and Risk of Obesity in Preschool-Aged Children” by Susanna Huh et al. found that among formula fed infants or infants weaned before four months of age, introduction of solid foods before four months increased the odds of obesity at three years of age.*
Researchers studied 847 children, enrolled in Project Viva, a prospective cohort study of infants and children, and examined the timing of their introduction to solid foods, categorized as <4 months, 4-5 months, and ≥ 6 months. Subjects were divided into two groups: breastfed children (defined as infants who were breastfed for at least four months) and formula fed infants (those who were never breastfed or stopped breastfeeding before four months of age) and analyses were performed, adjusting for various potential confounders for both the infant and the mother. Because the study was neither controlled nor randomized, cause and effect could not be determined.
In this cohort, 75 children (9%) were considered obese by three years of age. Researchers found that among breastfed infants, the timing of the introduction of solid foods was not associated with the odds of obesity, but among formula fed infants, introduction of solid foods before 4 months of age was associated with a six fold increase in the odds of obesity. The authors failed to provide information on the type and amount of complementary foods that were provided. Other studies have indicated that these differences might play an important role in establishing a pattern leading to later life obesity.
In this study, the exclusivity of breastfeeding was not assessed, nor were infants who were breastfed less than four months examined independently (e.g., infants breastfed for less than four months were analyzed together with infants who were exclusively formula fed). Further, lost-to-follow-up subjects in this cohort were relatively high, limiting the ability to generalize the findings. A strength of this study was the inclusion of adjustment for many potential infant and maternal confounders in the various statistical models presented; however, more research is needed to evaluate the role of the type and quantity of complementary foods provided.
This study adds to the growing body of evidence suggesting that the timing of the introduction complementary foods can have an impact on later life obesity risk. The findings of this study agree with the recommendations of the American Academy of Pediatrics (AAP) that parents should delay the introduction of solids until at least four – six months of age. The World Health Organization also recommends delayed introduction of complementary foods until six months of age.
It is important that the introduction of complementary foods be considered when evaluating the relationship between infant feeding and later life obesity, as the authors conclude, “increased adherence to guidelines regarding the timing of solid food introduction may reduce the risk of obesity in childhood.”
* Huh SY, Rifas-Shiman SL, Taveras EM, Oken E, Gillman MW. Timing of solid food introduction and risk of obesity in preschool-aged children. Pediatrics;127(3):e544-51.