The simple reason why breastfeeding is NEVER a substitute for vaccination


I’m going to lead this piece with the “money quote” so if you read nothing else you’ll read this:

Breastfeeding can NEVER be a substitute for vaccination for a very simple reason: maternal antibodies to vaccine preventable diseases CAN’T be passed via breastmilk.


[pullquote align=”right” cite=”” link=”” color=”” class=”” size=””]Maternal antibodies to vaccine preventable diseases are not and CANNOT be passed via breastmilk.[/pullquote]

The immune system makes different types of antibodies (immunoglobulins) labeled alphabetically. Immunoglobulin A (IgA) can be passed through breastmilk. IgA can protect against colds and diarrheal illnesses but NOT other illnesses.

The antibodies that fight vaccine preventable diseases are IgG. Vaccines stimulate the production of IgG. IgG can be passed across the placenta but CAN’T be passed in breastmilk. So babies can be born with some immunity to vaccine preventable diseases, but that immunity immediately begins to wane. It is not replaced by breastfeeding because there is no IgG in breastmilk.

Why do anti-vaccine parents think breastmilk is a substitute for vaccination?

According to Martucci and Barnhill, it is because we have over-emphasized the “naturalness” of breastfeeding.

InUnintended Consequences of Invoking the “Natural” in Breastfeeding Promotion in the journal Pediatrics they claim:

Medical and public health organizations recommend that mothers exclusively breastfeed for at least 6 months. This recommendation is based on evidence of health benefits for mothers and babies, as well as developmental benefits for babies. A spate of recent work challenges the extent of these benefits, and ethical criticism of breastfeeding promotion as stigmatizing is also growing… Promoting breastfeeding as “natural” may be ethically problematic, and, even more troublingly, it may bolster this belief that “natural” approaches are presumptively healthier. This may ultimately challenge public health’s aims in other contexts, particularly childhood vaccination.

Martucci and Barnhill have focused on an important issue. However, it seems to me that it isn’t merely the naturalness of breastfeeding that has emboldened anti-vax parents to insist that vaccination isn’t necessary for breastfed babies. They’ve been emboldened by irresponsible claims of specific immunological benefits of breastfeeding.

For example, the Baby Friendly Hospital Iniatitive claims:

Human milk provides the optimal mix of nutrients and antibodies necessary for each baby to thrive.

That’s utterly FALSE. Breastfeeding CAN’T provide antibodies for vaccine preventable diseases.

Claims about the immune benefits of breastfeeding are often utterly irresponsible.

Writer Angela Garbes claimed in In The More I Learn About Breast Milk, the More Amazed I Am:

According to Hinde, [Katie Hinde, a biologist and associate professor at the Center for Evolution and Medicine at the School of Human Evolution & Social Change at Arizona State University] … If the mammary gland receptors detect the presence of pathogens, they compel the mother’s body to produce antibodies to fight it, and those antibodies travel through breast milk back into the baby’s body, where they target the infection.

That’s pure speculation on Hinde’s part, as she later acknowledged in a public Twitter conversation with me.

I agree wholeheartedly with Martucci and Barnhill’s claim that touting breastfeeding as natural has serious unintended consequences (like maternal guilt for women who don’t breastfeed). Nonetheless, I suspect that it is the specific irresponsible false claims made by lactivists about the immunological benefits of breastfeeding that have led anti-vax parents to believe that breastfeeding is a substitute for vaccines.

We should think carefully before we tout breastfeeding as superior because it is natural, but it is even more important to hold lactivist organizations to account for all sorts of false claims, including immunological claims. In countries with reliable clean water supplies, the benefits of breastfeeding for term infants are limited to a few less colds and episodes of diarrheal illness across the entire population of infants (because of IgA in breastmilk). That’s it. Claims of other benefits are based on scientific evidence that is weak, conflicting and riddled with confounders. And in many cases, even that weak evidence was debunked long ago.

The key point, though, is that breastfeeding is NEVER a substitute for vaccination because IgG (the antibodies produced by vaccination) can’t be passed in breastmilk.

It’s just that simple.