For moms, breastfeeding may be a lifesaver. That's the takeaway from a new study analyzing the health and economic costs of not breastfeeding as medically recommended.

Researchers found that more than 3,340 premature deaths in the U.S. annually, and $3 billion in medical costs, were associated with so-called "suboptimal breastfeeding," meaning less than the medical recommendations of exclusive breastfeeding for six months with continued breastfeeding for one year for each child. The vast majority of the those deaths, notably heart attacks and diabetes in women and sudden infant death syndrome among infants, were maternal.

"Breastfeeding," the study concludes, "has a larger impact on women's health than previously appreciated."

I spoke with the study's lead author, Dr. Melissa Bartick, assistant professor of medicine at Harvard Medical School and a hospitalist at Cambridge Health Alliance. Here, lightly edited, are her thoughts on the new report, published online in the journal Maternal & Child Nutrition.

What surprised you about the these findings?

The most surprising thing is that breastfeeding is even more of a maternal health issue than a children's health issue. It has a bigger impact in terms of medical cost and a bigger impact in terms of lives saved. And most of that impact is derived from encouraging women to breastfeed as long as they can for each child. For example, if women optimally breastfeed — meaning breastfeeding for at least one year — and we got the current breast feeding rates from about 30 percent of mothers up to 90 percent, we could avert 5,023 cases of breast cancer per year. Put another way, you would need only about 397 women to optimally breastfeed to avert one case of breast cancer.

The numbers are even more dramatic for other diseases:

For hypertension, assuming the same scenario, you'd avert 35,392 cases and 322 deaths; and only 55 women would have to breastfeed to avert a case of hypertension.

For heart attacks, 235 women would have to breastfeed optimally to prevent a heart attack; 162 would need to breastfeed each child for one year to prevent a case of diabetes.

This is the first study that combines maternal and pediatric diseases into a single unified model; you can see the whole scope of the public health impact of breastfeeding. So, for instance, only 597 women or children would have to breastfeed (or be breastfed) optimally to prevent death from the 14 maternal or pediatric diseases we looked at.

How reliable are these numbers?

The numbers themselves are derived from other studies but we took the best studies and used conservative estimates ... the assumption is that there is a causal relationship between breastfeeding and these diseases based on the published studies.

In general, this still says that breastfeeding is an important public health issue — even here in the U.S. — and it's important as both a women's health issue and a children's health issue.

Doesn't this put even more pressure on women who choose not to breastfeed or have trouble breastfeeding?

I think the contrary. Now that we see that this is more of a women's health issue, we are taking the fuel out of the "Mommy Wars." This is something we should be doing to support women for their own health. This is not about who is a better mother; it's about women being supported to take care of themselves and about society taking care of women.

I think this takes all the steam away from critics who say it's about criticizing women for not breastfeeding. We have 60 percent of women who don't meet their own breastfeeding goals. Let's help women meet their own breastfeeding goals — now more than ever.

How do you hope this report might change public policy?

We're hoping that people will see the impact of the lives saved and the financial impact and that more public policies should be put in place to support women to breastfeed longer. I'm talking about paid family leave and breastfeeding support in the workplace and more acceptance of breastfeeding in public.

For example, there is the Supporting Working Moms Act of 2015 that would expand the Affordable Care Act so that it would not just apply to hourly employees, it would also apply to salaried employees. It would allow mothers reasonable break time to express milk at work. Paid family leave is an important policy that needs to be implemented. We hear almost every day about women being harassed for nursing in public. Even where there are laws protecting nursing women, women are still being harassed.

There's no federal law to protect breastfeeding in public at this point, there are only state laws and they are not uniform across the states; they're a hodgepodge and people are not aware of them. We need a better cultural acceptance of breastfeeding in public. Women are told to feed their babies in bathrooms ... you would never go eat in a bathroom.

There have been several studies and recent books, notably "Lactivism" by Courtney Jung, that suggest the benefits of breastfeeding have been overstated. In a similar vein, Dr. Amy Tuteur argues that there's just too much "bressure" on women to breastfeed. Obviously, you disagree, but what's your response to the breastfeeding backlash, in general?

We know that most women in the U.S. actually want to breastfeed. Over 80 percent of U.S. women initiate breastfeeding. Yet, data from the CDC show that 60 percent of women aren't meeting their own breastfeeding goals, even if those goals are modest. So, what we are really seeing is that women are not getting the support they need to breastfeed.

Some women don't want to breastfeed, and as long they are making an informed choice after discussing it with their health care provider, their choice should be respected by everyone around them. Some women quit breastfeeding for one reason or another — some by choice, and some not by choice. Women should be supported and respected. For many women, early weaning of their infants — especially when it is not by choice — is a time of personal grief, and I would hope that we can all be sensitive to that.

Here's a bit more on the specifics of the study, from the news release: