One thing to note about children's IQ is that, contrary to intuition, environmental factors tend to play a smaller overall role as the child mature into adult. Instead, their genetics seem to play a larger role.
As the children mature, the heritability of their IQ grows from roughly 0.45 to 0.8 (similar to height) [1]. The fact that the age of the child at the time of the IQ test is such a large factor is often not accounted for in research, which creates inconsistent results. Ideally, breastfeeding research would compare the IQ at adult age of children that were breastfed for different durations, normalized against their parents IQ.
“Various studies have found the heritability of IQ to be between 0.7 and 0.8 in adults”
However, it’s important to realize that environment is generally fairly constrained in these studies. A Twin study is hardly comparing Sierra Leone with Japan, or the Netherlands with North Korea. Extremes like iodine deficiency, disease, or fetal alcohol syndrome are similarly excluded.
Heritiblity of a trait is not traditionally determined in twins studies but can be done on any random sample of the general population.
FWIW, you see the similar trend in adopted children - as they grow older, their IQ trends from being close to their adoptive parents to getting closer to their (completely uninvolved) biological parent.
Comparing random members of the general population has both genetics and environmental factors. To isolate the role of either genetics or the environment you need to then control the other factor thus twins for genetics or unrelated people who grow up in similar environments. But both of those comparisons run into problems if these differences don’t represent the full scope of differences with the added issue of similar environments not actually being identical.
>However, it’s important to realize that environment is generally fairly constrained in these studies. A Twin study is hardly comparing Sierra Leone with Japan, or the Netherlands with North Korea. Extremes like iodine deficiency, disease, or fetal alcohol syndrome are similarly exclude.
except if you look at the other comparisons made (eg. "Unrelated children—Reared together—Adults "), the correlation factor can go quite a bit lower than 0.7-0.8 (eg. 0.04). The fact the correlation can go this low casts doubt on your theory that the environment is "constrained".
This is a universal complaint that can apply to almost any heritability study. And I'm not aware of any situations where a further investigation found it to be devastating to the original conclusion (mainly because actually covering all the edge cases you're calling out is somewhere between "cost prohibitive" and "impossible").
That makes me think it's just a generic "I don't like this conclusion so I'll criticize it" Joker card that people play, and not a legitimate debunking.
> A Twin study is hardly comparing Sierra Leone with Japan, or the Netherlands with North Korea. Extremes like iodine deficiency, disease, or fetal alcohol syndrome are similarly excluded.
Sure. To take this line of reasoning to its conclusion, an environment that has no oxygen or is otherwise uninhabitable, would prevent any human from living or having any mental abilities whatsoever. In this sense, environmental influences would completely dominate genetics. Similarly, changing 50% of a human's DNA would have them live life as a stalk of wheat.
Do you consider breastfeeding to be an environmental factor?
Breastmilk contains the most microRNA of any body fluid[1] and has the potential to modulate gene expression, so there may be ways breastfeeding affects the genome that we don't understand yet. How long a child is breastfed is associated with epigenetic differences in children.[2]
Breastfeeding is negatively associated with the methylation of LEP. Childhood obesity is associated with lower cognitive performance.[3]
If people have looked this hard and have found only tiny effects like 2 or 3 iq points, it suggests the effect is probably closer to zero due to scientists tendency to lean towards significance.
Maybe one way to think about it is this: walk into an elementary school and interact with kids in a classroom for any amount of time you want, access all their test scores. Then guess which kids were breastfed and which were not. I would bet that you wouldn’t do much better than chance.
The only way you would beat chance would be if breastfeeding were the primary predictor of some sort of observable behavior. Obviously it’s not. But there’s a wide range between zero and the primary factor.
That seems a rather pointless way to think about it, unless you think any science that can't be proven with a brief conversation with someone isn't worth considering. Would you try to judge how many kids in the class have inherited higher risk of heart disease by listening to their heart beats for a few minutes?
If you spent a day with a class of kids you'd probably (unless asking them specific questions about it) not be able to guess any specifics of their parents' different parenting techniques, does that mean that parenting doesn't matter and kids should just be ignored when not being fed?
One can definitely figure out which kids were coming from troubled homes. Teachers often notice outlier behaviours and report them to higher ups to get help for these children.
The effect of having loving parents completely dominates whether you breastfeed or bottle or formula.
1) Because large effects are more robust than tiny effects to things like researcher bias, choice of statistical methods, and experimental error.
2) because perturbing large effects are more likely to see real world difference for every day life than small effects. The conclusion from studies of breastfeeding versus bottle is it does not matter because it is a tiny and likely negligible effect (even if the effect is highly statistically significant).
Also n=2 and controlled experiment are so generic that it becomes a joke itself.
And a paper? Wow, you probably never read a paper. A high school course report would be more meaningful than a few sentences.
Overall, I am absolutely abhorred by the lack of intelligence of this comment.
We also had good experience and it seemed a lot easier when looking at parents using formula. Easy for me to say as the father but mother agreed. She didn't work though which is a luxury not everyone can afford unfortunately.
Nobody wants to think they're a bad parent and the vast commercial interests here don't make this any easier.
"My pool of the scientific method is very bad and would never pass the test, but here my findings on science of 2 kids who I did not give any other context for"
That is just down to chance. I reckon it has more to do with genetics/hygiene and their school cohort. Also covid is going to skew this a lot! Not just the virus but the societal reaction to it, norms, etc.
Well, our pediatrician told us that breastfeeding milk brings more antibodies to the infants. That's one thing definitely helps with fending off minor illness.
Never understood the fascination of Americans for breastfeeding (and the crazy crazy associated shame for mothers who don’t breastfeed in the upper middle class): the data is garbage (as this article shows, , there’s no studies, and entire high income countries like France or China have low breastfeeding rates, and kids in those countries are obviously not stupid.
In my experience it’s been the opposite. There’s stigma around breastfeeding in public. People aren’t breastfeeding and using formula because of a lack of education and the associated stigma.
I don’t think this has been the case for the past 15 years or so. In young parent culture, there is absolutely stigma against using formula.
I think these studies are a big part of it. There’s pressure from doctors and hospital staff to breastfeed when you have a new baby, and a key part of the sales pitch is increased IQ. It’s not hard to see how that causes serious guilt for moms who use formula.
When we had kids (party recently), there was education about breastfeeding but I did not see pressure and zero mention of IQ. They did have tables showing the nutrients in Breastmilk vs formula. That itself was scientific. No judgement either way. In fact they did mention they understand some families can’t or decide they don’t want to.
Then you had a great hospital! My wife and I had our child in late 2020, and our experience was vastly different and much like vlunkr said.
Ours UCSF, pressured and pressured my wife to breastfeed even though her milk was having massive problems coming in. Instead of allowing formula they only allowed donor breast milk supplementation by tubes that were taped to my wife's nipples, to attempt to prevent "nipple confusion".
Not OP, but we had to get a c section and milk production was slow to come in. We also used the breastfeeding aid, but with formula.
The way it was explained to us, the idea is to continue to stimulate milk production while supplementing. We used it for a week until production was sufficient. I personally enjoyed this as it allowed me to be more involved and removed the stress of knowing if we were feeding our child enough while still getting what we could from breastfeeding.
We definitely had a great hospital. With all the stress and lack of sleep, I'm not sure I would've kept calm if they'd imposed stuff that way. Not letting you the choice of using formula when using the breastfeeding aid seems crazy.
The author is only tackling the IQ studies. I think the multitude of other benefits (https://en.wikipedia.org/wiki/Breastfeeding) aren’t really debated because it’s proven medically.
In the absence of health issues to the mother, breastfeeding is always preferable.
Co sleeping is also good for attachment and mental health (and probably the default for most of our ancestors), but we discourage it due to worries about SIDS...
I don't think it's SIDS so much as smothering that's the issue, is it?
It was such a blessing. We got better sleep (tried it both ways), kid got fed more efficiently so wake time was shorter, nice bonding. Neither parent was so heavy a sleeper as to be a danger, no one was intoxicated either.
Many of the asian countries where co-sleeping is the norm have lower incidence of SIDS. The SIDS seem to be a bigger risk when the parents consume alcohol/other intoxicants.
Co-sleeping in an attached cot is encouraged in some European countries AFAIK. And I know families that have used the same bed; even we did that on some days, it can be quite nice :-)
It’s important to never drink alcohol or go to bed impaired in any way.
I have to agree with the argument that the prior should be that breastfeeding is beneficial and we would need massive and strong evidence to the contrary to change that position. It is an expensive process so it must have an evolutionary advantage.
The analysis presented here seems convincing in the sense that we don’t have good evidence that breastfeeding increases IQ. But from what I remember there is good evidence that it improves the baby’s immune system among many other things.
So bottom line is in the absence of massive amounts of strong evidence against breastfeeding, by default you should favour it. And if in the end the IQ effect isn’t real at least you improved your baby’s health (and hence survival chances). If you have the option to breastfeed, go for it.
And as the article stated, if for whatever reason you cannot or will not you probably don’t need to feel too bad about it because the effects while positive are at the margin to the best of our current knowledge and formula is getting better every decade.
The analysis is actually quite different. Bottle feeding has massive advantages for division of labor among parents. I did all the night feedings for my first two kids so my wife could get some much needed sleep. She didn’t have to pump which is often so much trouble it’s not worth it. Moreover, they now associate me with being the nighttime parent, so when they’re sick or having trouble sleeping I’m the one they come to, not mom.
Losing that flexibility would be worthwhile only if there was strong evidence that breastfeeding had advantages that can’t be replicated with formula. On that front it should be noted that the vast majority of GenX and older millennials were formula fed, as breastfeeding rates plummeted in the 1970s and 1980s. If there was a massive impact from that it would have been apparent.
It just feels weird to run this random experiment on my current child. Is evolution/biology wrong, and this processed stuff from the store better?? You'd have to have shocking amounts of studies to convince me it's better to have a baby eat that fake stuff than a mother's breast milk.
And finally, I think it's incredibly selfish to argue about equitably splitting feeding times, at the likely expense of your child's health and growth.
Young adults and men seem to be less healthy than ever. Plummeting testosterone, crazy rates of allergies, increased suicide rates, high depression.... But your right, if feeding them processed junk was bad, we'd see signs of it by now.
Young adults being less healthy than ever would argue against breastfeeding, which was at its nadir 2 generations earlier, and has been on the rise ever since.
Yes evidently many children grow up fine on formula. So given that the effect of breastfeeding is capped, it’s reasonable to choose to optimise for other factors such as practicality, father-child bonding time and so on.
As a counterpoint I’ll say that to the extent that the transfer of antibodies prevents or reduces infant illness, that is a win in the dimensions you describe on its own. A sick infant is both wildly impractical and hard to bond with.
For example, in this interventional cohort study with breastfeeding promotion [1], ”the percent of children having pneumonia and gastroenteritis declined 32.2% and 14.6%, respectively, after the intervention.”
> Yes evidently many children grow up fine on formula. So given that the effect of breastfeeding is capped, it’s reasonable to choose to optimise for other factors such as practicality, father-child bonding time and so on.
Does breastfeeding negatively impact father-child bond ? I find it highly unlikely. We do know for a fact that it’s better for health.
Exclusive breastfeeding means the mother's presence is essential, she has to be available most of the time as the primary care giver. Due to the way modern societies and nuclear families work, it's reasonable to assume that it's unlikely both partners would take long term leave to be with the infant, or that the father could be there anywhere near the same amount of time as the mother. So the infant would have far more time to bond with the mother than with the father. Whether this time alone is enough to guarantee a stronger bond is probably worth a separate discussion.
I’m talking about the logistics of men taking on more of the woman’s traditional caregiver role in couples where both people work. In that respect breastfed babies (or even babies who drink pumped milk) are much more dependent on their mothers. With our first two, who were bottle fed, it was more convenient for my wife to go on a business trip in the first year or two than me. My third was breastfed for six months, and he was highly reliant on my wife in a way the others were not.
And the science shows that the health benefits are minimal.
Breastfed children tend to have less stomachaches. When your baby cries because he cannot digest the formula, you arguably lose a big part of the benefits.
Also breastfeeding is much more convenient when traveling.
I think using formula was heavily promoted as a way to establish equality, and many people turned a blind eye on the drawbacks for the sake of progress.
It’s a good thing that we are now prioritizing babies’ health.
> Breastfed children tend to have less stomachaches.
Maybe on average, but specific cases can vary wildly. Some foods that the breastfeeding mother consumes can cause issues. Milk, soy, and caffeine are known troublemakers - but good luck finding out which one is the source of stomach issues for your baby!
I think we’re both on the same page. I’m all for breastfeeding and it’s what we’re currently doing and plan on continuing for atleast two years (along with other food of course).
I worried about things like this when I found out that we would have to formula feed our baby. But then I dug into the literature and found that the effect in most cases, while statistically significant, were very minor. Usually just a few percentage points different. And that's not to be interpreted as "kids who were formula fed were 2% sicker or scored 1% lower on tests". It's more like, out of the group of kids we studied, some formula fed kids scored higher and others scored lower. But it averaged out to a few points lower.
There are so many other, much more important factors in raising a healthy kid. The breastfeeding vs formula is hardly worth the brainpower.
This is an absurd case parent-shaming. Most parents already have a high level of anxiety that they are not doing enough for their kids. Let's not shame them for getting sleep so that they can be awake and have better interactions with their children.
Also, outright calling someone a bad parent because you don't agree with one of their methods is unnecessarily cruel.
A few hours of extra sleep can be the difference between a functional and non-functional household.
People don't often seem the grasp the variability of the difficulties that different babies can throw at parents. It really is just harder for some parents than others.
Grow up. People are different than you. You don't know their life and you obviously haven't experienced enough of the world to recognize how difficult it can be for some mothers to get enough sleep to function. Especially if she is recovering from a difficult pregnancy and/or delivery. Add to that the high incidence of post-partum depression and losing sleep can be all the more damaging.
As our very pro-breastfeeding lactation consultant wisely told us with our first child, "Breastfeeding is best, but your child will benefit so much more from a mentally well and rested mother."
Personal attacks (and there is nothing more personal than parenting) will get you banned here.
You have a long history of breaking the site guidelines and we've already had to warn you with this account as well. I don't want to ban you again, but we need you to follow HN's rules. If you'd please review https://news.ycombinator.com/newsguidelines.html and stick to them, we'd appreciate it.
Again, that'd be an argument against breastfeeding, given that millenials were born at a peak time for breastfeeding. Really, though, it's probably got nothing to do with breastfeeding.
The father can do everything except breastfeeding, so there’s no reason (except illness) to divide labour on exactly the thing that evolution built the mother to do.
There are cots which attach to the parent’s bed and special blouses which allow for easy breastfeeding without undressing.
The whole process is as simple as dragging the baby over, taking one breast out and bringing them near to it. The baby will take care of the rest.
Mothers do get sleep, including during the day together with the baby. There are solutions out there for many frequent or rare problems. A good midwife and experienced mothers in the family / circle of friends are priceless.
Who gives a shit how evolution "built the mother"? It also built us to walk the plains and jog slowly after ruminants for hours on end to feed our tribes. In 2022, what the mother probably needs to do is get up in the morning reasonably refreshed and get in to her office.
The WHO and any local health org worth its salt cares. Parents that want the best for their baby do. The more appropriate question is who wants to ignore the medical consensus and why.
Of course some women can’t breastfeed and they deserve support. But downplaying the benefits of breastfeeding because it may hurt the feelings of some mothers is not the way to go.
It’s disappointing but not surprising that you’re saying that mothers need to go to work in the US. AFAIK in many parts of Europe they take many months off (often 6-12) to spend time with the baby. For some of them, it’s the only time in their life that they’ll get the chance to do that. Work can wait.
Why do mothers need to work in the US in the first 6 months of their baby’s life? Why can’t one of the richest countries in the world pay them to stay at home?
The rest of the thread discusses, and I think mostly debunks, the notion that breastfeeding is vitally important for infant health. I'm just here to take potshots at appeals to the naturalist fallacy, that if nature "designed" something some way, it's important for us to continue honoring that design. No, it isn't.
As for parental leave: why not pay men to stay home? Why the presumption that women must be the ones to sacrifice their careers? Because "breastfeeding"? That's a pitiful justification.
Thankfully nobody's likely to be reading HN for advice on breastfeeding, debunked or not. :-) They're going to look at the recommendations of the WHO, their country's equivalent or talk to their doctor or midwife. All of which would recommend breastfeeding, since that's the current scientific consensus. The EU in particular highlights the importance of breastfeeding for at least six months.
I'll say this though - breastfeeding can be a complete mystery for new parents and doctors are often clueless about it. A competent midwife which is familiar with the typical issues is priceless. It's good that there's formula available for those cases where the woman can't breastfeed or the baby is having difficulties and the parent's don't know what to do and can't find competent help.
In the EU, the parents get a number of months which can be split between them. Fathers in Germany for example take a few months off. Because breastfeeding, because moms often want to spend time with their babies and yes, sadly often also because they earn more.
The way you phrase this makes it sound like your experiences (direct or indirect) with breastfeeding have been easy. You should know that it can be very difficult for a lot of mothers, in any number of ways.
Having such a strong prior on preferring it has made many people's lives much harder than necessary.
On the contrary, it was not easy at all but that’s a story for another day.
My argument is merely that our opening position, until proven otherwise, should be that the child benefits. (It can, unfortunately, simultaneously be hard for the mother and beneficial for the child. Many aspects of parenting are.)
And again I do think it’s important to note that huge numbers of children grow up well on formula. So if breastfeeding doesn’t work out for whatever reason there’s no reason to lose sleep over it. We can suspect it is beneficial and yet make a rational choice to forego it based on other factors.
If it doesn’t work then it doesn’t work, ok, use formula. But if those sacrifices are things like being tired, sore breasts, etc there are normal and there are solutions available.
If his way of "trying to feel better about it" was to critically analyze and summarize 30 (or maybe 100) years of published research on the subject, then he's a hero in my mind. I'd choose to take that over your 100 bucks any day of the week.
Can anybody TL;DR this? I tried scrolling past the thousands of words to find a conclusive sentence and it basically just said “Why does nobody know about this?”
This does not elicit faith that the author has any insight whatsoever.
Edit:
I’m not particularly motivated by talk of IQ in general because the groups that get fixated on it rarely have overlap with my own interest in human cognition. I’ve found this stuff to often be sensationalist navelgazing nothingness at best.
TLDR: breastfeeding has a lot of benefits but IQ is not consistently correlated in the literature.
I find IQ topics go as you suggest, generally.
Parenting topics around IQ are a slightly different beast: middle-class American parents (at least) are obsessed with making their baby smarter than your baby. It has been a thing for 35+ years. Something about the competitiveness of the boomers in the mid-80s spiked a baby IQ frenzy that has only worsened.
I think the author is very smart at selling Substack Subscriptions to post-COVID moms.
Dear prospective parents, esp first time parents, hoping to be perfect parents, I just want to tell you, after 4 kids, just do what works for you.
Your sanity has a bigger influence on the well being of your child than any single factor like religiously breastfeeding.
Breastfeeding is incredibly convenient when the mom is not working, and cost efficient. But if it becomes impossibly inconvenient or costly, eg while mom is working, dont beat yourself up if you have to resort to formula to bridge the gaps.
Also, baby formula marketing would lead you to believe that formula with omega3 will make your babies smarter too. That's probably the lie you should disbelieve in.
Raising a confident well adjusted child is more important to me than high IQ, and there is no objective way to measure that.
Nothing wrong with wanting to be a good parent... But yes, everyone will have (conflicting) advice for you but you are the parents. Nature will do its thing anyways.
I won't argue with you. But I will change the emphasis.
If you can breastfeed your baby, do it. Give it a real go.
But if it is leading to a true loss of sanity, let it go.
I've raised 3 and breastfeeding was a part of each baby's start. There were reasons why none of them made to the promoted 1 year target. But I saw real benefits that I associate with breastfeeding in each child up to today.
Is all breast milk made equal? Is it not possible that some mothers milk is deficient for some reason (diet, genetics, health issues etc)? It's not usually tested after a child is born.
No. There is variability in the nutrients, microRNA it contains, the microbiome and levels of heavy metals.
Diet before, during and after pregnancy can affect the nutritional composition, and it can be low in vitamin D, iodine, iron, and vitamin K. Vitamin D and K are usually supplemented (K is given at birth).
Some women (around 30% iirc, can't find the number atm) do not have B. infantis because of low gut diversity, which is really important for infant gut health and long term immunity. Infants are usually exposed during vaginal birth, so babies born by c-section are at risk for not having B. infantis colonize their gut. Breastmilk can be a source of B. infantis.
Some communities with heavy environmental contamination have had lead levels as high as 41.1 ppb [1]. Baseline heavy metal content for most areas tends to be more in line with formula.
Unrelated to the IQ question, AIUI not all formula is created equally.
One of the things that caused Robert Lustig [0] to go down the "fructose is a poison" rabbit-hole was he had parents with obeseinfants coming to him for help. What he found was the WIC-provided formula these mothers were giving these children was full of fructose making the infants obese. I think you'd struggle to produce a similar outcome via breastfeeding.
Quite. When there’s a profit motive behind one of two things being compared, and the other is the way things have been for quite literally millions of years, skepticism towards the former should be turned up to full.
This applies to any other long term study of whether X affects Y in human. Now replace X with coffee, wine, fruits, medicine... and replace Y with IQ, cancer risk, mental health, ....
Emily Oster has reviewed the literature pretty comprehensively and the best evidence we have is that breastfeeding has some short term benefits over formula, especially if you live somewhere without safe water. But no significant long term benefits.
Bf is really hard for a lot of women, and other women (me) don’t enjoy it. It’s really painful in the beginning, means that I’m solely responsible for feedings and night wakeups, puts me at risk of mastitis, thrush and postpartum depression (probably exacerbated by lack of sleep), requires me to stay close to home for months. There’s nothing special about breastfeeding apart from this feeling people have that “natural” is better. You probably wouldn’t limit your own food intake to what’s “natural” - what you can kill or grow within walking distance of your home - why would you limit your baby’s in the same way?
> ... and postpartum depression (probably exacerbated by lack of sleep)
I remember back in the early 2010's there was this 'hack' going around where you could manage to only sleep for 2 hours or something a day, but you had to grab sleep every 4 hours for 15 minutes to get the REM cycle in. I'm likely totally off on the schedule, but the gist was very little sleep.
Recently, a sibling became a parent and I was reminded of that 'hack' and told them. My sibling just laughed and said 'Oh, so nerds discovered motherhood huh?'.
My interpretation is that after removing the social bias which is usually prevalent in related studies and discussions, not much of an effect can be observed.
126 comments
[ 5.0 ms ] story [ 187 ms ] threadAs the children mature, the heritability of their IQ grows from roughly 0.45 to 0.8 (similar to height) [1]. The fact that the age of the child at the time of the IQ test is such a large factor is often not accounted for in research, which creates inconsistent results. Ideally, breastfeeding research would compare the IQ at adult age of children that were breastfed for different durations, normalized against their parents IQ.
https://en.wikipedia.org/wiki/Heritability_of_IQ#:~:text=Ear....
However, it’s important to realize that environment is generally fairly constrained in these studies. A Twin study is hardly comparing Sierra Leone with Japan, or the Netherlands with North Korea. Extremes like iodine deficiency, disease, or fetal alcohol syndrome are similarly excluded.
FWIW, you see the similar trend in adopted children - as they grow older, their IQ trends from being close to their adoptive parents to getting closer to their (completely uninvolved) biological parent.
except if you look at the other comparisons made (eg. "Unrelated children—Reared together—Adults "), the correlation factor can go quite a bit lower than 0.7-0.8 (eg. 0.04). The fact the correlation can go this low casts doubt on your theory that the environment is "constrained".
“Same person (tested twice) .95 Identical twins—Reared together .86 Fraternal twins—Reared together .55 Biological siblings—Reared together .47 Unrelated children—Reared together .30 Parent-child—Living together .42 Adoptive parent – child – Living together 0.19 Identical twins—Reared apart .76 Fraternal twins—Reared apart .35 Biological siblings—Reared apart .24”
So siblings reared apart had less correlation than unrelated children living together.
Like what “raised separate” means.
Was one raised in a Soviet gulag while the other was raised in an Israeli kibbutz?
That makes me think it's just a generic "I don't like this conclusion so I'll criticize it" Joker card that people play, and not a legitimate debunking.
Sure. To take this line of reasoning to its conclusion, an environment that has no oxygen or is otherwise uninhabitable, would prevent any human from living or having any mental abilities whatsoever. In this sense, environmental influences would completely dominate genetics. Similarly, changing 50% of a human's DNA would have them live life as a stalk of wheat.
What's your point?
Breastmilk contains the most microRNA of any body fluid[1] and has the potential to modulate gene expression, so there may be ways breastfeeding affects the genome that we don't understand yet. How long a child is breastfed is associated with epigenetic differences in children.[2]
Breastfeeding is negatively associated with the methylation of LEP. Childhood obesity is associated with lower cognitive performance.[3]
1. AAP talk on long term breastfeeding epigenetic effects: https://www.youtube.com/watch?v=-bUeSqPOCTc
2. https://pubmed.ncbi.nlm.nih.gov/32443666/
3. https://onlinelibrary.wiley.com/doi/10.1002/oby.22192
Maybe one way to think about it is this: walk into an elementary school and interact with kids in a classroom for any amount of time you want, access all their test scores. Then guess which kids were breastfed and which were not. I would bet that you wouldn’t do much better than chance.
If you spent a day with a class of kids you'd probably (unless asking them specific questions about it) not be able to guess any specifics of their parents' different parenting techniques, does that mean that parenting doesn't matter and kids should just be ignored when not being fed?
The effect of having loving parents completely dominates whether you breastfeed or bottle or formula.
1) Because large effects are more robust than tiny effects to things like researcher bias, choice of statistical methods, and experimental error.
2) because perturbing large effects are more likely to see real world difference for every day life than small effects. The conclusion from studies of breastfeeding versus bottle is it does not matter because it is a tiny and likely negligible effect (even if the effect is highly statistically significant).
The older one had not enough breastfeeding and had much more minor illness over the years.
The younger one had all breastfeeding during the early time and only had 2 illness in the similar time period.
As for others, I cannot comment yet. Let's see.
Also n=2 and controlled experiment are so generic that it becomes a joke itself. And a paper? Wow, you probably never read a paper. A high school course report would be more meaningful than a few sentences.
Overall, I am absolutely abhorred by the lack of intelligence of this comment.
Quickthrower2's first sentence is the useful one.
Nobody wants to think they're a bad parent and the vast commercial interests here don't make this any easier.
I don't think we have enough data.
In my experience it’s been the opposite. There’s stigma around breastfeeding in public. People aren’t breastfeeding and using formula because of a lack of education and the associated stigma.
I think these studies are a big part of it. There’s pressure from doctors and hospital staff to breastfeed when you have a new baby, and a key part of the sales pitch is increased IQ. It’s not hard to see how that causes serious guilt for moms who use formula.
Of course this is anecdata.
Ours UCSF, pressured and pressured my wife to breastfeed even though her milk was having massive problems coming in. Instead of allowing formula they only allowed donor breast milk supplementation by tubes that were taped to my wife's nipples, to attempt to prevent "nipple confusion".
The way it was explained to us, the idea is to continue to stimulate milk production while supplementing. We used it for a week until production was sufficient. I personally enjoyed this as it allowed me to be more involved and removed the stress of knowing if we were feeding our child enough while still getting what we could from breastfeeding.
We definitely had a great hospital. With all the stress and lack of sleep, I'm not sure I would've kept calm if they'd imposed stuff that way. Not letting you the choice of using formula when using the breastfeeding aid seems crazy.
Or breastfeeding from a wet nurse vs breastfeeding from one's biological mother?
Sounds like we still know so little, but I'd be curious about these two questions as well.
Breastfeeding is important for attachment and mental health, see:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1459116/#:~:tex....
In the absence of health issues to the mother, breastfeeding is always preferable.
It was such a blessing. We got better sleep (tried it both ways), kid got fed more efficiently so wake time was shorter, nice bonding. Neither parent was so heavy a sleeper as to be a danger, no one was intoxicated either.
It’s important to never drink alcohol or go to bed impaired in any way.
The analysis presented here seems convincing in the sense that we don’t have good evidence that breastfeeding increases IQ. But from what I remember there is good evidence that it improves the baby’s immune system among many other things.
So bottom line is in the absence of massive amounts of strong evidence against breastfeeding, by default you should favour it. And if in the end the IQ effect isn’t real at least you improved your baby’s health (and hence survival chances). If you have the option to breastfeed, go for it.
And as the article stated, if for whatever reason you cannot or will not you probably don’t need to feel too bad about it because the effects while positive are at the margin to the best of our current knowledge and formula is getting better every decade.
Losing that flexibility would be worthwhile only if there was strong evidence that breastfeeding had advantages that can’t be replicated with formula. On that front it should be noted that the vast majority of GenX and older millennials were formula fed, as breastfeeding rates plummeted in the 1970s and 1980s. If there was a massive impact from that it would have been apparent.
And finally, I think it's incredibly selfish to argue about equitably splitting feeding times, at the likely expense of your child's health and growth.
Young adults and men seem to be less healthy than ever. Plummeting testosterone, crazy rates of allergies, increased suicide rates, high depression.... But your right, if feeding them processed junk was bad, we'd see signs of it by now.
Young adults and men are less healthy than ever because we play on our computers instead of tilling soil and fighting in wars.
It is associated with less GI infections, ear infections, asthma, lower blood pressure, lower cholesterol and risk of type 2 diabetes.
1. https://www.researchgate.net/publication/261881391_Epigeneti...
2. https://www.sciencedirect.com/science/article/pii/S193131282...
As a counterpoint I’ll say that to the extent that the transfer of antibodies prevents or reduces infant illness, that is a win in the dimensions you describe on its own. A sick infant is both wildly impractical and hard to bond with.
For example, in this interventional cohort study with breastfeeding promotion [1], ”the percent of children having pneumonia and gastroenteritis declined 32.2% and 14.6%, respectively, after the intervention.”
[1] https://www.nec.navajo-nsn.gov/Portals/0/NN%20Research/Biolo...
Does breastfeeding negatively impact father-child bond ? I find it highly unlikely. We do know for a fact that it’s better for health.
Exclusive breastfeeding (not exclusively feeding breastmilk, but exclusively breastfeeding) would to a certain extent, yes.
In early stages of life the mother’s presence will never not be essential.
And the science shows that the health benefits are minimal.
All the nurses, midwives, and doctors I know declare otherwise
Also breastfeeding is much more convenient when traveling.
I think using formula was heavily promoted as a way to establish equality, and many people turned a blind eye on the drawbacks for the sake of progress.
It’s a good thing that we are now prioritizing babies’ health.
Maybe on average, but specific cases can vary wildly. Some foods that the breastfeeding mother consumes can cause issues. Milk, soy, and caffeine are known troublemakers - but good luck finding out which one is the source of stomach issues for your baby!
Regarding milk, avoiding it for a few days and checking for improvements is enough to see if it’s the culprit.
There are so many other, much more important factors in raising a healthy kid. The breastfeeding vs formula is hardly worth the brainpower.
Also, outright calling someone a bad parent because you don't agree with one of their methods is unnecessarily cruel.
People don't often seem the grasp the variability of the difficulties that different babies can throw at parents. It really is just harder for some parents than others.
As our very pro-breastfeeding lactation consultant wisely told us with our first child, "Breastfeeding is best, but your child will benefit so much more from a mentally well and rested mother."
You have a long history of breaking the site guidelines and we've already had to warn you with this account as well. I don't want to ban you again, but we need you to follow HN's rules. If you'd please review https://news.ycombinator.com/newsguidelines.html and stick to them, we'd appreciate it.
That's the conclusion of a new study that looked at markers of physical and mental health across the generations."[1]
Of course, there could be many reasons for that.
[1]https://www.webmd.com/a-to-z-guides/news/20210325/gen-x-mill...
The whole process is as simple as dragging the baby over, taking one breast out and bringing them near to it. The baby will take care of the rest.
Mothers do get sleep, including during the day together with the baby. There are solutions out there for many frequent or rare problems. A good midwife and experienced mothers in the family / circle of friends are priceless.
Of course some women can’t breastfeed and they deserve support. But downplaying the benefits of breastfeeding because it may hurt the feelings of some mothers is not the way to go.
It’s disappointing but not surprising that you’re saying that mothers need to go to work in the US. AFAIK in many parts of Europe they take many months off (often 6-12) to spend time with the baby. For some of them, it’s the only time in their life that they’ll get the chance to do that. Work can wait.
Why do mothers need to work in the US in the first 6 months of their baby’s life? Why can’t one of the richest countries in the world pay them to stay at home?
As for parental leave: why not pay men to stay home? Why the presumption that women must be the ones to sacrifice their careers? Because "breastfeeding"? That's a pitiful justification.
I'll say this though - breastfeeding can be a complete mystery for new parents and doctors are often clueless about it. A competent midwife which is familiar with the typical issues is priceless. It's good that there's formula available for those cases where the woman can't breastfeed or the baby is having difficulties and the parent's don't know what to do and can't find competent help.
In the EU, the parents get a number of months which can be split between them. Fathers in Germany for example take a few months off. Because breastfeeding, because moms often want to spend time with their babies and yes, sadly often also because they earn more.
Having such a strong prior on preferring it has made many people's lives much harder than necessary.
My argument is merely that our opening position, until proven otherwise, should be that the child benefits. (It can, unfortunately, simultaneously be hard for the mother and beneficial for the child. Many aspects of parenting are.)
And again I do think it’s important to note that huge numbers of children grow up well on formula. So if breastfeeding doesn’t work out for whatever reason there’s no reason to lose sleep over it. We can suspect it is beneficial and yet make a rational choice to forego it based on other factors.
There is a good reason they tell you to put your own oxygen mask on before helping your child in the case of a depressurizing plane.
I think it just protects them while they are fed, does not offer long term protection.
Anecdotally ours started to get way more sick in daycare after we stopped breastfeeding, but it also coincided with autumn season.
>But from what I remember there is good evidence that it improves the baby’s immune system among many other things.
>So bottom line is in the absence of massive amounts of strong evidence against breastfeeding, by default you should favour it.
These are all bad arguments.
It does, it means that newborns don't have to be born developed enough to get their own food.
Even more so it's developing a formula milk industry; it's got to be a huge advantage.
This does not elicit faith that the author has any insight whatsoever.
Edit:
I’m not particularly motivated by talk of IQ in general because the groups that get fixated on it rarely have overlap with my own interest in human cognition. I’ve found this stuff to often be sensationalist navelgazing nothingness at best.
I find IQ topics go as you suggest, generally.
Parenting topics around IQ are a slightly different beast: middle-class American parents (at least) are obsessed with making their baby smarter than your baby. It has been a thing for 35+ years. Something about the competitiveness of the boomers in the mid-80s spiked a baby IQ frenzy that has only worsened.
I think the author is very smart at selling Substack Subscriptions to post-COVID moms.
Your sanity has a bigger influence on the well being of your child than any single factor like religiously breastfeeding.
Breastfeeding is incredibly convenient when the mom is not working, and cost efficient. But if it becomes impossibly inconvenient or costly, eg while mom is working, dont beat yourself up if you have to resort to formula to bridge the gaps.
Also, baby formula marketing would lead you to believe that formula with omega3 will make your babies smarter too. That's probably the lie you should disbelieve in.
Raising a confident well adjusted child is more important to me than high IQ, and there is no objective way to measure that.
If you can breastfeed your baby, do it. Give it a real go.
But if it is leading to a true loss of sanity, let it go.
I've raised 3 and breastfeeding was a part of each baby's start. There were reasons why none of them made to the promoted 1 year target. But I saw real benefits that I associate with breastfeeding in each child up to today.
Diet before, during and after pregnancy can affect the nutritional composition, and it can be low in vitamin D, iodine, iron, and vitamin K. Vitamin D and K are usually supplemented (K is given at birth).
Some women (around 30% iirc, can't find the number atm) do not have B. infantis because of low gut diversity, which is really important for infant gut health and long term immunity. Infants are usually exposed during vaginal birth, so babies born by c-section are at risk for not having B. infantis colonize their gut. Breastmilk can be a source of B. infantis.
Some communities with heavy environmental contamination have had lead levels as high as 41.1 ppb [1]. Baseline heavy metal content for most areas tends to be more in line with formula.
1. https://jpnim.com/index.php/jpnim/article/view/040223
One of the things that caused Robert Lustig [0] to go down the "fructose is a poison" rabbit-hole was he had parents with obese infants coming to him for help. What he found was the WIC-provided formula these mothers were giving these children was full of fructose making the infants obese. I think you'd struggle to produce a similar outcome via breastfeeding.
[0] https://profiles.ucsf.edu/robert.lustig
Reduces `type 2 diabetes` risk. https://www.nmcd-journal.com/article/S0939-4753(13)00274-3/f...
It reduced the risk of reduced risk of breast cancer, ovarian cancer, and endometrial cancer. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4670483/
Do I need to mention maternal bond as well as weight loss? Instead of dieting or stuff like that, it's a more healthier option.
Just see the 1970s Nestle scandal. https://en.wikibooks.org/wiki/Professionalism/The_Nestl%C3%A...
See also sunscreen [1].
[1]: https://www.outsideonline.com/health/wellness/sunscreen-sun-...
https://www.who.int/health-topics/breastfeeding
Too clever by half springs to mind with this article.
Bf is really hard for a lot of women, and other women (me) don’t enjoy it. It’s really painful in the beginning, means that I’m solely responsible for feedings and night wakeups, puts me at risk of mastitis, thrush and postpartum depression (probably exacerbated by lack of sleep), requires me to stay close to home for months. There’s nothing special about breastfeeding apart from this feeling people have that “natural” is better. You probably wouldn’t limit your own food intake to what’s “natural” - what you can kill or grow within walking distance of your home - why would you limit your baby’s in the same way?
I remember back in the early 2010's there was this 'hack' going around where you could manage to only sleep for 2 hours or something a day, but you had to grab sleep every 4 hours for 15 minutes to get the REM cycle in. I'm likely totally off on the schedule, but the gist was very little sleep.
Recently, a sibling became a parent and I was reminded of that 'hack' and told them. My sibling just laughed and said 'Oh, so nerds discovered motherhood huh?'.
My interpretation is that after removing the social bias which is usually prevalent in related studies and discussions, not much of an effect can be observed.