Thursday, October 30, 2014

Biomarkers and milk: Halloween Edition! Old & Scary Milk Myths

Myth #1: Colostrum is poison

The perhaps best known myth about human milk relates to the first milk – colostrum. Many, many cultures have strong beliefs and folklore about colostrum. The most common belief is that colostrum is bad and should not be given to the infant.

As far back as the 1500s, it was regularly suggested that infants should be breastfed by another woman for the first three to fourteen days of life, or sometimes as long as two months, because her milk was “not healthy”. Colostrum especially, because of its sharp visual contrast to mature milk, has had numerous beliefs about it. Some physicians at the time recommended feeding colostrum to a puppy or an adult in order to maintain milk supply. If the mother had to nurse, she should first give the child honey. Gruel was also an acceptable substitute. 

Figure 1: Puppies should not nurse from humans. Dressing them as nurses on Halloween though, is totally okay. Photo: Pinterest.

Yeah, you read that right. Women’s colostrum, the thick, wonderful substance commonly called “liquid gold” because of its richness in immune factors and benefits to the infant was fed to puppies. It is almost certain this contributed to both infant and maternal morbidity and mortality, as newborn infants received consider immunological support from the immunoglobulins in milk and mothers nursing puppies may have been at increased risk of mastitis. “Milk fever” was at one point considered a stage of lactation (Obladen, 2012). 

Fortunately, by around the 1750s, a few physicians figured out that this was probably not the best advice, and started recommending infant breastfeeding within a few hours of birth. This had a beneficial effect on infant mortality rates, as it turns out puppies aren’t very good at removing milk, and too often, by the time the 3-14 days had passed, the woman had no milk and would have to rely on animal milks or gruels and paps. 

The scary part? In many parts of the world, myths persist about colostrum. In my work in Tibetan communities in the highlands of Nepal, more than half the mothers did not breastfeed their infant for the first 3 days and about 10% told us that the first milk was poisonous. When we asked why, several reported that a nurse had provided that piece of information. 

Myth #2: Bad behavior makes bad milk

If you are what you eat, then you are what you make for someone else to eat, or so the story goes. It was long believed that maternal characteristics were in the milk, and while an upstanding lady with a good husband might make good, upstanding milk, she probably wasn’t nursing the baby – a wet nurse was. And finding a good, morally upright wet nurse (that is, someone to nurse your child instead of their own) was a bit complicated. If her baby had died, was her milk any good? If her baby was born out of wedlock, would she pass “moral looseness” onto the child? The ideal candidate was a morally upstanding, lower middle class woman with her own child . . .who could be farmed out to a lower class woman for cheaper wet nursing . . .who could feed her child gruel or other substitutes.  And of course, the wet nurse had to be not only morally upright but free from hysteria, angry thoughts, and “violent afflictions of the mind” that might give the baby rickets, or epilepsy.
Figure 2: Darth Vader as a baby. Likely candidate for moral failings, but blaming milk seems a bit over the top. Unless the Emperor was nursing.

Rickets of course, comes from a lack of Vitamin D, not afflictions of the mind, and epilepsy is not linked with milk in any way shape or form. What is described here is control over women, and specifically control over women’s bodies and reproductive potential. Delicate upper class women could certainly nurse – but because of high childhood mortality, were often instead relegated to repeated, closely spaced pregnancies while infants were fed by wet nurses or artificial means. Their capacity to bear numerous legitimate heirs for a husband was more important than their role in keeping the child alive. Additionally, the idea that bad behavior in milk could affect the infant was a means of social control, limiting women’s capacity to act, circumscribing their behavior and using infant morbidity and mortality as a means of social control over women. 

Sadly, as with the colostrum myths, ideas about maternal behavior and milk quality continue to this day in many parts of the world. An example of this comes from rural Bangladesh, where young married women’s low status within their husband’s families are often associated with limited food and harsh treatment, especially from mother in laws. Many women will substitute paps or gruels for milk, told that their milk is bad because they are disobedient or abused by their mother in law.

Myth #3: Breastfeeding makes your breasts sag

This one is one of my favorites, and is one you will often hear whispered among contemporary American women. Breastfeeding makes your boobs sag. You may have heard it. You may have said it. You may have thought it. It may have been said to you.

But is it true?

Figure 3: This boob hat might sag during breastfeeding . . .from a milk coma! Hats by:

NOPE!!!!!! Everyone take a deep breath and dance around with that joyful news, because we once again have science on our side. Rinker et al., (2007) looked at changes in the position of the mammary glands in women who breastfed and women who did not. The results? There was no difference in the amount of structural loss integrity (a nice way of saying sag) between the women that breastfed and the women that used formula. It was pregnancy, not breastfeeding that lead to the changes in collagen and support for the breasts!
On that happy note, have a nice Halloween, and remember: colostrum = good, behavior doesn’t influence milk, and breastfeeding does not cause breasts to sag.