The Effect of Diabetes on Mothers' Milk
by Anne Eglash MD, IBCLC, FABM
Breastmilk has been found to protect from childhood obesity and chronic diseases, and recently we learned, in the previous CQW 180, that one mechanism of breastmilk's effect is an increased amount of mitochondrial DNA among adolescents who were breastfed.
The authors of this week's article explored the research regarding whether maternal gestational diabetes mellitus or insulin-dependent diabetes mellitus alters the characteristics of milk such that the milk components no longer protect infants from obesity or chronic disease.
This article is a literature review of 29 studies done on breastmilk composition and either maternal gestational diabetes mellitus or maternal insulin-dependent diabetes mellitus.
Several studies contradict each other. For example, some studies showed a decrease in lipid content, and others showed an increase. One study showed an increase in IgA, the other showed a decrease. Overall, there were a few consistent findings, such as reduced levels of Ghrelin in colostrum and mature milk among the diabetics. Ghrelin is an appetite hormone that increases food intake.
There are several breastmilk components for which only one study has been done, so no conclusions can be drawn.
- No one really knows
See the Answer
Human milk (HM) is a unique nourishment believed to contain biological factors contributing to both short and long-term benefits. Considering that a mother’s own milk is often considered the first choice for nutrition of neonates, an aspect of increased interest is the possible effect of diabetes on the mammary gland and therefore on breast milk composition. This article aims to review the published literature on this topic, and to offer additional insights on the role of this disease on the composition of HM. This review was performed by searching the MEDLINE, EMBASE, CINHAL and Cochrane Library databases. A total of 50 articles were selected, focused specifically on one of the two types of diabetes: gestational diabetes mellitus (21 studies) and insulin-dependent diabetes mellitus (8 studies). Overall, the findings from the literature suggest that diabetes can alter the composition of HM. Nevertheless, the studies in this field are scarce, and the related protocols present some limitations, e.g., evaluating the variability of just a few specific milk biochemical markers in association with this syndrome.
The bottom line is that we don’t have enough research to fully understand the impact of maternal gestational diabetes or insulin dependent diabetes on the composition of breastmilk. There are only 2 studies on the glucose level in breastmilk among mothers who have high blood sugars during lactation (insulin-dependent mothers). One study demonstrated high glucose levels in breastmilk, and the other did not. We need more data on this. For now, there is every reason to believe that the breastmilk of a mother with diabetes protects, supports, and matures the infant just as well as that from a mother of a nondiabetic.
Further, infants of diabetic mothers have a higher genetic risk of diabetes, so breastfeeding the infant should help to lower that risk by reducing the risk of childhood obesity and insulin resistance.