47 breastfeeding leads to lower blood pressure in 7-year-old japanese children

Background and Objective: Beneficial effects of breastfeeding have been established. However, few studies have investigated the association between the young children's blood pressure (BP) and their history of breastfeeding. The purpose of this study is to investigate the associations between breastfeeding and self-measured home blood pressure (HBP) as well as conventional blood pressure (CBP) in 7-year-old Japanese children. Method: We obtained information about breastfeeding and BP data for 377 mother-offspring pairs from the Tohoku Study of Child Development, a prospective birth cohort study. Information about the breastfeeding and other factors was obtained from frequent parental survey questionnaires during follow-up. According to the duration of breastfeeding as a major source of nutrition, mother-offspring pairs were divided into short (mean 5.1 months) and long (11.3 months) breastfeeding groups. Results: At age seven (84.4 ± 1.8 months), children's BP were measured. Their HBP in the long breastfeeding group (92.8 mmHg for systolic/ 55.0 mmHg for diastolic) was significantly lower (P = 0.006/0.03) than that in the short breastfeeding group (94.5/56.3 mmHg), whereas there were no significant differences in children's CBP between the short and long breastfeeding groups. In multiple regression analysis, the duration of breastfeeding (over 8 months) was more strongly associated with HBP (P = 0.01/0.06) than CBP (P = 0.4/0.8). Furthermore, adjusted R-squared values for HBP (0.25/0.12) tended to be higher than those for CBP (0.07/0.04). These findings were independent of birth weight in children. Conclusions: Breastfeeding has a protective effect against elevation of BP, and subtle but important differences could be precisely detected by HBP.