OAKLAND, Calif. – Breastfeeding with no or little formula supplementation was associated with lower fasting blood glucose and lower insulin levels at 6-9 weeks postpartum, according to Kaiser Permanente Researchers. They explain that this suggests that breastfeeding a child has favorable effects on glucose metabolism and insulin sensitivity in women. Researchers are also examining whether fully breastfeeding reduces diabetes risk in women with gestational diabetes during pregnancy.
The study appears online in the current issue of Diabetes Care.
Moms who exclusively breastfed or mostly breastfed (less than 6 ounces of formula per 24 hour period), had lower adjusted fasting plasma glucose levels, compared to moms who exclusively or mostly formula fed (greater than 17 ounces of formula per 24 hour period). Exclusive or mostly breastfeeding groups also had lower prevalence of pre-diabetes than formula feeding groups, even among obese women, explained Erica P. Gunderson PhD, an epidemiologist and research scientist with the Kaiser Permanente Northern California Division of Research and the lead author of the study.
Previous research has shown that breastfeeding has long-term favorable effects on a mother’s cardio-metabolic profile. This is the first study to examine breastfeeding intensity (degree of formula supplementation) as it relates to postpartum glucose tolerance, and insulin resistance among women with a history of gestational diabetes, explained Gunderson.
The analysis includes participants enrolled between September 2008 and March 2011 into the Study of Women, Infant Feeding and Type 2 Diabetes, SWIFT, an ongoing study of Kaiser Permanente Northern California members who experienced a diagnosis of gestational diabetes.
The findings support the hypothesis that breastfeeding spares insulin response required for similar or even improved levels of glucose control, said Gunderson. When women breastfeed, about 50 grams/day of glucose is diverted for the process of milk production without insulin, she explained. Thus, breastfeeding women exhibit lower blood glucose and insulin concentrations compared with non-breastfeeding women.
“We hypothesize that the diversion of glucose and lipids for milk production may unload the pancreatic beta cells and preserve long-term insulin production in women,” said Gunderson.
Additional authors on the study include: Monique Hedderson, PhD; Vicky Chiang, MS; Yvonne Crites, MD; David Walton, MS; Robert Azevedo, MD; Gary Fox, MD; Cathie Elmasian, MD; Stephen Young, MD; Nora Salvador, MD; Michael Lum, MD; Charles Quesenberry, PhD; Joan Lo, MD; Barbara Sternfeld, PhD; Assiamira Ferrara, MD, PhD; all with Kaiser Permanente. Co-author Joe Selby, MD, is with the Patient Centered Outcomes Research Institute (PCORI). The study was funded by the National Institute of Child Health and Human Development.
About the Kaiser Permanente Division of Research (http://www.dor.kaiser.org/)
The Kaiser Permanente Division of Research conducts, publishes and disseminates epidemiologic and health services research to improve the health and medical care of Kaiser Permanente members and the society at large. It seeks to understand the determinants of illness and well-being and to improve the quality and cost-effectiveness of health care. Currently, DOR’s 400-plus staff is working on more than 250 epidemiological and health services research projects.