Ever wonder if the lipid profile of breastmilk, which differs from that of formula, can play a role in future cardiometabolic health? We already know that exclusive breastfeeding is associated with reductions in obesity, diabetes, and hypertension. In a new study early released this month, Hui et al. (10.1542/peds.2018-3075) used a population birth cohort in Hong Kong (the “Children of 1997” study) and followed more than 3200 of these children from birth to 17.5 years of age. After adjusting for a number of potential confounders including pregnancy history, birth weight, gestational age, and other factors associated with cardiometabolic health, and compared infants exclusively breastfed for at least the first 3 months of life to those fed mixed feedings of breastmilk and formula and those fed only formula. The results may surprise you in that those infants who were exclusively breastfed had lower total cholesterol and low-density lipoprotein cholesterol in adolescence; however, there was no difference in body mass index or other markers of adiposity.
Do these findings suggest that exclusive breastfeeding can be associated with a healthier cardiovascular status as we get older? On the surface, one might say yes, but we asked Dr. Alex Krist (10.1542/peds.2019-0447), a member of the United States Preventive Services Task Force to weigh in with an accompanying commentary that might dampen your enthusiasm for the importance of these study findings. While the study size was large and representative of the diversity of Hong Kong, and longitudinal in its design, the number of infants exclusive breastfed was small (only 7.5%) and the drop in LDL cholesterol with exclusive breastfeeding was only 4.6 mg/dl which may not be clinically important for future risk, especially when other stronger risk factors (e.g., smoking) may begin. Regardless of how strong the association is in this study, there are plenty of other reasons to advocate for exclusive breastfeeding in the first year of life. Keeping abreast of the pediatric literature for more information about the long-term impact of breastfeeding.