Breastfeeding Lowers a Mother’s Type 2 Diabetes Risk

There have been a lot of links drawn between breastfeeding and a person’s type 2 diabetes risk, both for the mother and her offspring.

But how breastfeeding affects these changes on the metabolic system is not well understood. This is especially true when looking at the apparent reduced risk for type 2 experienced by mothers who breastfed.

Hoping to learn more about these processes, Maria A. Ramos-Roman, MD (bio), and her team at UT Southwestern (website) completed an in-depth study into the differences between insulin resistance in breastfeeding mothers and those feeding formula only. 

Their results help shed some light not only on the type 2 connection but on why some mothers may struggle to make enough milk and how science may be able to help.

What We Know About Breastfeeding and Type 2

Breastfed infants have been found to have a 39% lower risk of developing type 2 as adults compared to infants who were formula-fed. Interestingly, there is a similar reduction in risk for the development of type 1 diabetes.

Even among adults who don’t develop diabetes, those breastfed as infants show reduced fasting insulin concentrations compared to those who weren’t.

But the benefits of breastfeeding don’t just extend to the child. Mothers have a 14% reduced risk of developing type 2 for each year they breastfeed. 

Interestingly, though, when breastfeeding mothers were compared to women who had not been pregnant, the risk for type 2 was similar. Conversely, mothers who did not breastfeed showed a 50% increased risk for type 2 compared to women who had never been pregnant.

These statistics reveal an interesting connection between breastfeeding, pregnancy, and diabetes. It appears that pregnancy, itself, increases a woman’s risk of type 2 diabetes. But breastfeeding after pregnancy negates this increased risk.

This makes sense considering the extreme insulin resistance that occurs in all women during pregnancy.

In order to supply the growing fetus with the nutrients they need, the mother’s cells must take up less glucose. Increased insulin resistance helps accomplish this and allows for higher glucose concentrations in the blood that the baby can then use for themselves.

Once the baby is born, it would make sense that the body would undergo a process to reverse this metabolic change. Breastfeeding appears to assist in this process. How, exactly, this works is the question Dr. Ramos-Roman’s team hoped to answer.

New Research Helps Us Understand 

The researchers out of UT Southwestern followed 18 women.

• 12 women who had recently given birth and who were exclusively breastfeeding or feeding less than 6oz of formula per day
• Six new mothers who were exclusively formula feeding.

The results of the study were recently published in Diabetes.

All the women in the study had low blood insulin concentrations, which is a well-documented characteristic of women in the postpartum stage.

Despite similar low insulin levels, the lactating mothers produced two and a half times more glucose following a 12 hour fast compared to the non-lactating mothers. These results show an increase in insulin sensitivity in the breastfeeding mothers. 

This insulin sensitivity was most apparent in the highly insulin-sensitive cells of the liver and fatty tissues. 

In addition to showing an increase in glucose and lipid release during times of fast, the lactating women were more likely to hold onto stored fat after eating or after simulated conditions of “fed state.” This demonstrates clear changes in metabolism aimed at maximizing nutrients available for milk production.

These same changes to insulin sensitivity and insulin production are likely to create a buffer against insulin resistance. One that, apparently, can last for decades after the mother has stopped breastfeeding.

How these Findings Help New Mothers

In addition to answering some of the questions about how breastfeeding and type 2 risks are connected, this research also has the potential to benefit new mothers who are struggling to produce enough milk to breastfeed.

By stimulating insulin-sensitive organs like fatty tissues and the liver into releasing more nutrients into the bloodstream during fasting states and into holding onto stored fat when glucose is plentiful, it may be possible to increase a mother’s milk supply.

It may even be possible to use these methods to simulate the metabolic changes successful breastfeeding mothers experience in order to reduce the mother’s future risk for type 2, regardless of whether she chooses formula or breastmilk for her baby.

Source: University of Texas Release ‘Breastfeeding’s legacy may protect against diabetes’