As more research becomes available, it is increasingly clear that breastfeeding children provides infinitely more long-term health benefits to both baby and mom. Now, a new study shows that mothers who breast feed run a lower risk of developing Alzheimer's disease later in life.
The research indicates the link may have something to do with key biological effects of breastfeeding. Scientists also found that breastfeeding for longer periods of time decreased overall risk.
Previous studies have established that breastfeeding can reduce a mother's risk of other diseases but until now little has been done to examine the impact of breastfeeding duration on Alzheimer's risk.
Biological changes could be responsible for the additional protection
Researchers from the University of Cambridge's Department of Biological Anthropology conducted the study using data gathered from a relatively small group of 81 women. But, they said, the correlation between breastfeeding and Alzheimer's was especially consistent and significant, though it was much less common in women who had a history of dementia in their family.
The findings could lead to new ways to combat what is being called a global Alzheimer's epidemic. Also, researchers note that the study could offer some indications as to why some people are more susceptible to developing the disease than others.
The study argues that there may be a number of biological reasons for the connection between Alzheimer's and breastfeeding. One theory is that breastfeeding deprives the body of the hormone, progesterone, compensating for high levels of progesterone which are produced during pregnancy.
Researchers note that progesterone is known to have a desensitizing effect on the brain's oestrogen receptors; it may also play a role in protecting the brain against Alzheimer's, they add.
Still another possibility: Breastfeeding boosts a woman's glucose tolerance by restoring her sensitivity to insulin following pregnancy, which in and of itself "induces a natural state of insulin resistance and Alzheimer's is characterized by a resistance to insulin in the brain," the Telegraph reported.
"Women who spent more time pregnant without a compensatory phase of breastfeeding therefore may have more impaired glucose tolerance, which is consistent with our observation that those women have an increased risk of Alzheimer's disease," Dr. Molly Fox, who led the study, said.
"Alzheimer's is the world's most common cognitive disorder and it already affects 35.6 million people. In the future, we expect it to spread most in low and middle-income countries. So it is vital that we develop low-cost, large-scale strategies to protect people against this devastating disease," she said.
Prior research has established that breastfeeding can lower a mum's risk of other diseases and a possible link between breastfeeding and cognitive decline later in life. But until now, little work has taken place on the effect on Alzheimer's of the length of time women breastfeed for.
More research is warranted, but so far, it's promising
The 81 women involved in the study were between 70 and 100 years old. Fox, along with Prof. Carlo Berzuini and Prof. Leslie Knapp interviewed the women; they discovered that "women who breastfed were less likely to have developed the disease and the threat fell still further for those with a longer history of breastfeeding," Cambridge said, in a press release.
Researchers said the link between breastfeeding and Alzheimer's was not affected by other factors such as the drinking and smoking history of the women, education history, age or other variables.
The university said its researchers hope the study will lead to more research into the relationship between the risk of Alzheimer's and the reproductive history of women.