Pregnancy causes many metabolic changes with post-meal sugar and triglyceride fluctuations and insulin secretion. A new 30-year study shows that breastfeeding protects against the subsequent onset of diabetes.
Normally, breastfeeding rapidly decreases circulating triglycerides in the mother’s blood, as well as sugar. At the same time, the secretion of insulin also decreases and mobilizes the reserves of the fatty tissue.
Large prospective studies of women of North European or Asian origin show relatively small decreases in diabetes risk of 3 to 15% per year of breastfeeding.
The CARDIA (Coronary Artery Risk Development In Adults) study was conducted over 30 years. It is the only one to take into account all the factors that can interfere with the result: possible obesity before the beginning of the pregnancy, gestational metabolism, problems during childbirth, socio-demographic data and behaviors related to the way of life following birth.
It reveals that the increase in the importance and duration of breastfeeding is associated with a 34 to 57% decrease in diabetes over 2 years. These results were published in JAMA in early March 2018.
In practice, the CARDIA study shows that the association between duration of breastfeeding and incidence of diabetes in women of childbearing age is characterized by a gradual reduction in risk ranging from 25% for 6 months or less, to 47% for 6 months of breastfeeding or more. Overall, the authors found an excess risk of diabetes associated with no breastfeeding compared to 12 months of breastfeeding. The hypothesis is that increased resistance to insulin could interfere with lactogenesis after delivery.
The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists recommend breastfeeding for one year. In the United States only 35% of women breastfeed for 6 months. In general, breastfeeding rates are declining in countries with high socioeconomic status, particularly in South Asia, which is currently at the center of the global diabetes epidemic.
Lactation is a key strategy for the early primary prevention of metabolic diseases in women of childbearing age.