Follow Ups and Microplastics

First of all, I am so sorry that many of you read what I intended as funny sarcasm at the top of the last post as serious. I do not think suffering makes you a better parent! I feel terrible that people came away thinking that I think unmedicated birth makes you a better mom. I cannot promise to never try to be funny again, but I can promise to try to be clearer when I am.

Second, this is somewhat random, but we all need a little joy. Do your kids like to bake or do you wish they did? If yes, this book is awesome. Cookie pie highly recommended.

Today, a few follow-ups from previous newsletters in response to questions. Also, microplastics.

Tongue Tie

I wrote about Tongue Tie here. I would briefly summarize the main point of that post as there is some data suggesting surgery to fix tongue tie lower breastfeeding pain, but it’s not overwhelming and there isn’t much good evidence of improved breastfeeding.

In response to this a number of people wrote me to say three things. First, they distinguished between “anterior” and “posterior” tongue tie, with the first being significantly more serious. Second, several people contributed their personal annec-data, pointing out that their breastfeeding experience was dramatically different immediately after this surgery. Third, several people pointed out that the evidence in favor of less pain shouldn’t be dismissed. True!

(A bunch of other people wrote in to say that this didn’t work for them, or their professional experience is that it’s pushed on too many women, etc.)

I mention this because, first, this distinction between anterior and posterior seems important. An anterior tongue tie, in which the membrane is attached at the front of the mouth, is both rarer and more restrictive than posterior. At a minimum, if you’re being evaluated for this, it’s worth figuring out what level the tie is at. But, more broadly, it’s clear from the emails I got that for some people this makes a huge difference. The trouble is likely coming when a solution which works for some people in a particular setting becomes a fix-all for any problem with breastfeeding.

Breastmilk: What about Deep Freeze?

Many people were reassured by the post on re-freezing breast milk, but also wondered about long-term freezing. Can you use breast milk after more than a year in the freezer?

As in the question of re-freezing, this isn’t that difficult to answer and it’s medically relevant due to the use of donor milk. So we have reasonably good evidence, which generally suggests some small loss in nutritional value (namely, fat) from longer in the freezer. See, for example, this study of 150 samples and this review article. There is some inconsistency in the review about moderate versus deep freezing. And the evidence is a bit incomplete. Specifically, they do not typically evaluate freezing beyond 6 months.

There’s nothing to suggest long-term frozen breastmilk will harbor pathogens, but it seems likely that there is some degradation of nutrients. I will say these figures are small — say, 3 to 10%. Put differently: if you feed your baby milk that has been frozen for 6 months, they might need more.

Breastfeeding and Pot

I wrote about pot in pregnancy, and immediately people asked. What about breastfeeding? It turned out I had written about this in Medium last year. Here’s the relevant paragraphs:

First, the active ingredient in marijuana, delta-9-tetrahydrocannabinol or THC, does pass into breast milk. The concentration is lower than in the mother, although unlike in the case of alcohol it seems like it may be higher than the concentration in maternal blood. Also unlike alcohol, it takes a long time to leave the bloodstream — counted in days, rather than hours. What’s more, data on infants has shown (through poop analysis) that infants do metabolize some THC when their mothers do. We know that THC has an effect on adult brains — indeed, this is why people like it — and it has been argued that long-term use may lead to cognitive impairments.

This all means it is possible that infants could be affected, although that is not the same as saying they are. Current research shows mixed results: At least one study argued that exposure to marijuana early in life lowers later motor development, but the sample is small at less than 150 infants studied, and it’s hard to separate early lactation use from pregnancy use. And other studies haven’t found this same effect. But the bottom line is there is almost no evidence either way — all together, existing studies do not cover more than a few hundred people.

Where does this leave us, other than desperately hoping for more data? Certainly the most cautious approach would be to avoid marijuana while breastfeeding. On the other hand, it would be a mistake to panic if you had some edibles a few times while nursing. Ultimately, there’s not enough data to say for certain one way or the other. For the time being, mothers will have to weigh their decision to use marijuana on personal factors.

Also one million people wrote to ask about CBD in pregnancy and breastfeeding and the answer is that we do not have any studies about this yet. I’m sorry! I’m sure these are coming given that CBD is now on offer everywhere I go, in everything.


Finally: something new. Last week NPR did a story on microplastics which left many people panicked (if you didn’t see it, maybe just skip this!). The story reported on new research on microplastics in baby bottles. The gist of it is that baby bottles release a lot of microplastic particles (literally, what they sound like: tiny plastic particles). This is especially true when heated, so if you prepare your formula with hot water (which you’re supposed to do to kill pathogens, although this also may be overkill) even more microparticles come out.

The NPR article is quite balanced and not alarmist, but it does contains statements like: The study suggests that bottle-fed infants around the world may be consuming more than 1.5 million particles of microplastics per day on average.  Many parents may find this concerning. It seems like a lot of particles!

However: it is totally unclear what this means. Humans consume a lot of microplastics. They are in a lot of our food (notably fish) and in many of our containers. We use a lot of plastic stuff, period. We poop out a lot of microplastic, which is one of the ways we know we consume it. Microplastics are bad for marine life and, generally, our use of plastic is extremely detrimental to the environment. BUT from the narrow standpoint of human health, the risks are really unclear.

We see some evidence of microplastic accumulation in mice and fish, although the clinical significance is unclear, as is the translation to people. I thought this article stated it nicely when they argued, basically, that there is too much speculative fear.

Another way to say this. With COVID-19, the upcoming election, and whatever other stuff you are dealing with, maybe just let this one go.

Weigh in!

Keep the thoughts coming. I cannot write back to everyone but I do read all of your emails, I promise.

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