Is There a Link Between BMI and Health?

Emily Oster

7 min Read Emily Oster

Emily Oster

Is There a Link Between BMI and Health?

Unpacking the data on weight

Emily Oster

7 min Read

In the past several months, we’ve had a number of posts about weight, food, and health. I interviewed Virginia Sole-Smith about her book Fat Talk: Parenting in the Age of Diet Culture and, separately, I wrote about Ozempic. In response to each of these, we got a lot of feedback and a lot of inquiries. At the top of the question pile was a request to help people better understand the link between BMI, or weight in general, and health.

This question isn’t just an academic one. From an individual standpoint, many people struggle to think about the right health choices — for them and their kids. And for at least some of those people, it’s clear they feel stuck between a message coming out of the medical establishment — lose weight for better health — and messages coming from other angles, arguing that health and size aren’t strongly linked and emphasizing that this link may actually be detrimental.  

This space is complicated from a data standpoint, as you’ll see below, but it’s also an emotionally complicated one. Very few of us have a totally straightforward relationship with food and our bodies. I’ve been reading Cole Kazdin’s new book, What’s Eating Us, which is wonderful and also a stark reminder that eating disorders are, in their various forms, rampant. 

So why write about this at all? As usual, I think data can help, because it can help us see why some groups might want to use a metric like BMI, what it would mean, and to think carefully about whether there is any value. That is what I’m going to try to do today.   

A note: This post will use the words “overweight” and “obesity” because those are used in the scientific literature and have technical meanings. 

And a further note: If this post isn’t for you today, please just skip it. I’ll be back later this week with one on doulas. 


Does BMI measure health? If not, what does it mean? 

I want to start with BMI itself. Stripped of other associations, this is just a number: weight in kilograms divided by height in meters squared. It is one of many ways you could imagine capturing a measure of individual body size. Having a standard metric for something like this can be useful for summarizing population characteristics and comparing across groups.

For example: Let’s say we want to compare the average body sizes for treatment and control groups in a randomized trial. Researchers need a simple way to do this that is consistent across studies. It is best if it doesn’t rely on more complex measurements (like body fat percentage). There are plenty of ways to do this (say, weight in pounds divided by height in feet), but this is the one the medical establishment chose.

Less obviously valuable but possibly still of some use is to divide this into categories. Sometimes we want to capture a feature of a distribution rather than just the average. It may be useful to compare, say, the proportion of people with a BMI over 35 in each of two groups in a study. To make the language more comparable, we can imagine labeling these groups in some way (e.g. BMI Group 1, BMI Group 2). 

Problems arise in these labelings, though — at least two of them. First: the nature of the labels. We’ve grouped and labeled BMI using terms that are not neutral. One could argue this didn’t have to be true, but I think that’s a hard sell. When you label one group “normal weight” and another group “overweight,” it’s difficult to claim neutrality.

A second problem emerges when we start to treat these labels and categories like they mean something. To see why this is, we can look at another example: birth weight. When babies are born, they have a birth weight, quoted in pounds or, in the scientific literature, usually in grams. Babies with very small birth weight are at higher risk for serious complications. At some point, there was a desire to have a way to summarize, at a population level, the share of babies who were in these higher-risk groups. So a convention was adopted: babies below 2,500 grams (about 5.5 pounds) were classified as “low birth weight” and babies below 1,500 grams (3.3 pounds) were classified as “extremely low birth weight.”

It should be obvious that there is no meaningful difference between a baby of 1,499 grams and one that weighs 1,501 grams — two grams is about the weight of a paper clip. These classifications were not designed to do anything other than describe the population in a standard way. And yet: over time, the existence of these cutoffs changed medical practice. In one of my favorite economics papers (see it here), researchers showed that babies born just below the 1,500-gram cutoff got more medical care than those born just above the cutoff and were more likely to survive. This is true even though, on average, higher birth weight increases survival. But because the medical system was reacting as if 1,500 grams actually meant something, they were under-treating babies just above the 1,500-gram cutoff (I wrote a bit more on that paper here).

This is a long digression, but I think it illustrates a general point in medicine, which is that there are a lot of cutoffs for diagnoses that are fairly arbitrary and that we have a tendency to overemphasize. The BMI cutoffs are similar. There is nothing magical about moving from a BMI of 24.9 to a BMI of 25.1. And by focusing on that, we may ignore other signs we should be paying attention to.

Bottom line: In my view, there is little reason to focus on BMI in individual care situations, and even less reason to get obsessed with cutoffs between BMI categories.

Thinking more broadly about weight and health

If we accept that BMI is just a number, and thinking in terms of categorical cutoffs is not useful, this leads to a second question. Is there a link between weight and health at all? That is, is a measure like BMI a signal (albeit an imperfect one) or is it just noise?

The simplest way to ask this is to look at the relationship between body size and health. We can take some metrics of health that we know to be related to morbidity and mortality and ask to what extent they reflect weight. For simplicity, I’m going to focus on two: high blood pressure and diabetes.

To do this analysis, I pulled data from the National Health and Nutrition Examination Survey, or NHANES, which is a nationally representative survey that collects data on many metrics of health. It’s a good data set for this type of analysis because it does not rely on self-reports for weight and health.

Let’s start with blood pressure. The graph below shows (using my calculations in the NHANES data) the distribution of systolic blood pressure for varying BMI groups. The dotted vertical line is at 130, the cutoff for a diagnosis of any hypertension. There is both signal and noise here. On average, blood pressure is higher for individuals with a higher BMI. But: the distributions overlap to a very great extent. There are plenty of people with a BMI below 25 who have high blood pressure, and plenty of people with a BMI over 40 who have normal blood pressure. (To be slightly more technical and precise: in a regression of systolic blood pressure on integer BMI measures, the R-squared is 0.019.)

Chart showing distribution of systolic blood pressure by BMI group

Turning to diabetes, the graph below shows the share of the population with diagnosed Type 2 diabetes by BMI group. Again, we see both signal and noise. Groups with higher BMI have a higher share of diabetes diagnoses. But also: among those with a BMI less than 25, diabetes diagnoses still occur in 6% of people, and among those with a BMI greater than 40, still only about a quarter report a Type 2 diabetes diagnosis.


We can see sources of some of this noise in the data. The graph below shows diabetes diagnosis rates by BMI group, separated into those who reported vigorous exercise in the past week versus those who did not. What is notable here is the protective effect of exercise. People with a BMI over 40 who report vigorous weekly exercise have diabetes rates similar to those with a much lower BMI with no exercise.


One argument that is sometimes made here is that the metric used is simply BMI but that other measures of body size — notably, waist circumference — are more predictive of health. It is absolutely true in the data that waist circumference has a stronger correlation with health. But the data is also very noisy.

Putting this all together, I see a moderate path. It is hard to look at the data and not conclude that body size, however you measure it, has a correlation with health outcomes. And everything we know biologically about metabolic health suggests there is a causal component. It is implausible to suggest that a larger body size is not a risk factor for diabetes, for example.

At the same time: presuming health — even metabolic health — based on a body size measure is subject to enormous error. Assuming that someone has serious health issues just because they are in a higher-BMI category will not be right and, similarly, assuming they do not have health issues in this category because they are in a lower-BMI category is also wrong.

So I guess everyone is both right and wrong, as usual.

A final thought (and a shout-out to Martinus Evans)

I want to pause a minute on the last graph. In a sense, underlying all the push to lose weight is the weight gradient in that graph. Health is worse at higher BMI, on average, and someone with a BMI of 40 is going to be told a version of Look at how much lower your diabetes risk would be if your BMI was 27. Go out there and lose weight. And we know, from a million studies of diet, that in almost all cases that will not happen, because weight loss at that scale (or really at all) is extremely difficult.

What if instead we looked at that graph and saw that the same decline in risk could be accomplished by adding exercise? In the graph, we’re just seeing a correlation, but there is quite a lot of randomized evidence on the value of some exercise for health, even moderate exercise like vigorous walking. You do not need to run many miles every day for these benefits. An after-lunch walk that gets your heart rate up a few times a week — that’s a start, and a good one.

I wonder if we’d be better off if we didn’t focus on weight at all, and instead got more focused on making exercise achievable and welcoming to everyone. We have work to do on this front. Time and space for exercise are not equitable, and too often people in larger bodies are made to feel excluded from sports. But I wonder if we spent as much time on this as we do on encouraging people to diet, we might make progress.

Inspirational weight-loss stories have always been popular (I’m looking at you, People magazine). Perhaps we could lean out on those and lean in on inspirational exercise, as in this amazing article about Martinus Evans.

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We are better writers than influencers, I promise. Thanks to our kids for filming our unboxing videos. People make this look way too easy. 

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We are better writers than influencers, I promise. Thanks to our kids for filming our unboxing videos. People make this look way too easy.

Only two weeks until our book “The Unexpected” is here! Preorder at the link in my bio. 💙
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Exciting news! We have new, high-quality data that says it’s safe to take Tylenol during pregnancy and there is no link between Tylenol exposure and neurodevelopmental issues in kids. Comment “Link” for a DM to an article exploring this groundbreaking study.

While doctors have long said Tylenol was safe, confusing studies, panic headlines, and even a lawsuit have continually stoked fears in parents. As a result, many pregnant women have chosen not to take it, even if it would help them.

This is why good data is so important! When we can trust the data, we can trust our choices. And this study shows there is no blame to be placed on pregnant women here. So if you have a migraine or fever, please take your Tylenol.

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Exciting news! We have new, high-quality data that says it’s safe to take Tylenol during pregnancy and there is no link between Tylenol exposure and neurodevelopmental issues in kids. Comment “Link” for a DM to an article exploring this groundbreaking study.

While doctors have long said Tylenol was safe, confusing studies, panic headlines, and even a lawsuit have continually stoked fears in parents. As a result, many pregnant women have chosen not to take it, even if it would help them.

This is why good data is so important! When we can trust the data, we can trust our choices. And this study shows there is no blame to be placed on pregnant women here. So if you have a migraine or fever, please take your Tylenol.

#tylenol #pregnancy #pregnancyhealth #pregnancytips #parentdata #emilyoster
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How many words should kids say — and when? Comment “Link” for a DM to an article about language development!

For this graph, researchers used a standardized measure of vocabulary size. Parents were given a survey and checked off all the words and sentences they have heard their child say.

They found that the average child—the 50th percentile line—at 24 months has about 300 words. A child at the 10th percentile—near the bottom of the distribution—has only about 50 words. On the other end, a child at the 90th percentile has close to 600 words. One main takeaway from these graphs is the explosion of language after fourteen or sixteen months. 

What’s valuable about this data is it can give us something beyond a general guideline about when to consider early intervention, and also provide reassurance that there is a significant range in this distribution at all young ages. 

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How many words should kids say — and when? Comment “Link” for a DM to an article about language development!

For this graph, researchers used a standardized measure of vocabulary size. Parents were given a survey and checked off all the words and sentences they have heard their child say.

They found that the average child—the 50th percentile line—at 24 months has about 300 words. A child at the 10th percentile—near the bottom of the distribution—has only about 50 words. On the other end, a child at the 90th percentile has close to 600 words. One main takeaway from these graphs is the explosion of language after fourteen or sixteen months.

What’s valuable about this data is it can give us something beyond a general guideline about when to consider early intervention, and also provide reassurance that there is a significant range in this distribution at all young ages.

#cribsheet #emilyoster #parentdata #languagedevelopment #firstwords
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I saw this and literally laughed out loud 😂 Thank you @adamgrant for sharing this gem! Someone let me know who originally created this masterpiece so I can give them the proper credit.

I saw this and literally laughed out loud 😂 Thank you @adamgrant for sharing this gem! Someone let me know who originally created this masterpiece so I can give them the proper credit. ...

Perimenopause comes with a whole host of symptoms, like brain fog, low sex drive, poor energy, and loss of muscle mass. These symptoms can be extremely bothersome and hard to treat. Could testosterone help? Comment “Link” for a DM to an article about the data on testosterone treatment for women in perimenopause.

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Perimenopause comes with a whole host of symptoms, like brain fog, low sex drive, poor energy, and loss of muscle mass. These symptoms can be extremely bothersome and hard to treat. Could testosterone help? Comment “Link” for a DM to an article about the data on testosterone treatment for women in perimenopause.

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What age is best to start swim lessons? Comment “Link” for a DM to an article about water safety for children 💦

Summer is quickly approaching! You might be wondering if it’s the right time to have your kid start swim lessons. The AAP recommends starting between 1 and 4 years old. This is largely based on a randomized trial where young children were put into 8 or 12 weeks of swim lessons. They found that swimming ability and water safety reactions improve in both groups, and more so in the 12 weeks group.

Below this age range though, they are too young to actually learn how to swim. It’s fine to bring your baby into the pool (if you’re holding them) and they might like the water. But starting formal safety-oriented swim lessons before this age isn’t likely to be very helpful.

Most importantly, no matter how old your kid is or how good of a swimmer they are, adult supervision is always necessary!

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What age is best to start swim lessons? Comment “Link” for a DM to an article about water safety for children 💦

Summer is quickly approaching! You might be wondering if it’s the right time to have your kid start swim lessons. The AAP recommends starting between 1 and 4 years old. This is largely based on a randomized trial where young children were put into 8 or 12 weeks of swim lessons. They found that swimming ability and water safety reactions improve in both groups, and more so in the 12 weeks group.

Below this age range though, they are too young to actually learn how to swim. It’s fine to bring your baby into the pool (if you’re holding them) and they might like the water. But starting formal safety-oriented swim lessons before this age isn’t likely to be very helpful.

Most importantly, no matter how old your kid is or how good of a swimmer they are, adult supervision is always necessary!

#swimlessons #watersafety #kidsswimminglessons #poolsafety #emilyoster #parentdata
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Can babies have salt? 🧂 While babies don’t need extra salt beyond what’s in breast milk or formula, the risks of salt toxicity from normal foods are minimal. There are concerns about higher blood pressure in the long term due to a higher salt diet in the first year, but the data on these is not super compelling and the differences are small.

Like with most things, moderation is key! Avoid very salty chips or olives or saltines with your infant. But if you’re doing baby-led weaning, it’s okay for them to share your lightly salted meals. Your baby does not need their own, unsalted, chicken if you’re making yourself a roast. Just skip the super salty stuff.

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Can babies have salt? 🧂 While babies don’t need extra salt beyond what’s in breast milk or formula, the risks of salt toxicity from normal foods are minimal. There are concerns about higher blood pressure in the long term due to a higher salt diet in the first year, but the data on these is not super compelling and the differences are small.

Like with most things, moderation is key! Avoid very salty chips or olives or saltines with your infant. But if you’re doing baby-led weaning, it’s okay for them to share your lightly salted meals. Your baby does not need their own, unsalted, chicken if you’re making yourself a roast. Just skip the super salty stuff.

#emilyoster #parentdata #childnutrition #babynutrition #foodforkids
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Among parenting topics, sleep training is one of the most divisive. Ultimately, it’s important to know that studies looking at the short- and long-term effects of sleep training show no evidence of harm. The data actually shows it can improve infant sleep and lower parental depression.

Even so, while sleep training can be a great option, it will not be for everyone. Just as people can feel judged for sleep training, they can feel judged for not doing it. Engaging in any parenting behavior because it’s what’s expected of you is not a good idea. You have to do what works best for your family! If that’s sleep training, make a plan and implement it. If not, that’s okay too.

What’s your experience with sleep training? Did you feel judged for your decision to do (or not do) it?

#sleeptraining #newparents #babysleep #emilyoster #parentdata

Is sleep training bad? Comment “Link” for a DM to an article breaking down the data on sleep training 😴

Among parenting topics, sleep training is one of the most divisive. Ultimately, it’s important to know that studies looking at the short- and long-term effects of sleep training show no evidence of harm. The data actually shows it can improve infant sleep and lower parental depression.

Even so, while sleep training can be a great option, it will not be for everyone. Just as people can feel judged for sleep training, they can feel judged for not doing it. Engaging in any parenting behavior because it’s what’s expected of you is not a good idea. You have to do what works best for your family! If that’s sleep training, make a plan and implement it. If not, that’s okay too.

What’s your experience with sleep training? Did you feel judged for your decision to do (or not do) it?

#sleeptraining #newparents #babysleep #emilyoster #parentdata
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Does your kid love to stall right before bedtime? 💤 Tell me more about their tactics in the comments below!

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Does your kid love to stall right before bedtime? 💤 Tell me more about their tactics in the comments below!

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Got a big decision to make? 🤔 Comment “Link” for a DM to read about my easy mantra for making hard choices. 

When we face a complicated problem in pregnancy or parenting, and don’t like either option A or B, we often wait around for a secret third option to reveal itself. This magical thinking, as appealing as it is, gets in the way. We need a way to remind ourselves that we need to make an active choice, even if it is hard. The mantra I use for this: “There is no secret option C.”

Having this realization, accepting it, reminding ourselves of it, can help us make the hard decisions and accurately weigh the risks and benefits of our choices.

#parentingquotes #decisionmaking #nosecretoptionc #parentingadvice #emilyoster #parentdata

Got a big decision to make? 🤔 Comment “Link” for a DM to read about my easy mantra for making hard choices.

When we face a complicated problem in pregnancy or parenting, and don’t like either option A or B, we often wait around for a secret third option to reveal itself. This magical thinking, as appealing as it is, gets in the way. We need a way to remind ourselves that we need to make an active choice, even if it is hard. The mantra I use for this: “There is no secret option C.”

Having this realization, accepting it, reminding ourselves of it, can help us make the hard decisions and accurately weigh the risks and benefits of our choices.

#parentingquotes #decisionmaking #nosecretoptionc #parentingadvice #emilyoster #parentdata
...

Excuse the language, but I have such strong feelings about this subject! Sometimes, it feels like there’s no winning as a mother. People pressure you to breastfeed and, in the same breath, shame you for doing it in public. Which is it?!

So yes, they’re being completely unreasonable. You should be able to feed your baby in peace. What are some responses you can give to someone who tells you to cover up? Share in the comments below ⬇️

#breastfeeding #breastfeedinginpublic #breastfeedingmom #motherhood #emilyoster

Excuse the language, but I have such strong feelings about this subject! Sometimes, it feels like there’s no winning as a mother. People pressure you to breastfeed and, in the same breath, shame you for doing it in public. Which is it?!

So yes, they’re being completely unreasonable. You should be able to feed your baby in peace. What are some responses you can give to someone who tells you to cover up? Share in the comments below ⬇️

#breastfeeding #breastfeedinginpublic #breastfeedingmom #motherhood #emilyoster
...

Potty training can feel like a Mount Everest-size challenge, and sadly, our evidence-based guidance is poor. So, I created a survey to collate advice and feedback on success from about 6,000 participants.

How long does potty training take? We found that there is a strong basic pattern here: the later you wait to start, the shorter time it takes to potty train. On average, people who start at under 18 months report it takes them about 12 weeks for their child to be fully trained (using the toilet consistently for both peeing and pooping). For those who start between 3 and 3.5, it’s more like nine days. Keep in mind that for all of these age groups, there is a range of length of time from a few days to over a year. Sometimes parents are told that if you do it right, it only takes a few days. While that is true for some people, it is definitely not the norm.

If you’re in the throes of potty training, hang in there! 

#emilyoster #parentdata #pottytraining #pottytrainingtips #toddlerlife

Potty training can feel like a Mount Everest-size challenge, and sadly, our evidence-based guidance is poor. So, I created a survey to collate advice and feedback on success from about 6,000 participants.

How long does potty training take? We found that there is a strong basic pattern here: the later you wait to start, the shorter time it takes to potty train. On average, people who start at under 18 months report it takes them about 12 weeks for their child to be fully trained (using the toilet consistently for both peeing and pooping). For those who start between 3 and 3.5, it’s more like nine days. Keep in mind that for all of these age groups, there is a range of length of time from a few days to over a year. Sometimes parents are told that if you do it right, it only takes a few days. While that is true for some people, it is definitely not the norm.

If you’re in the throes of potty training, hang in there!

#emilyoster #parentdata #pottytraining #pottytrainingtips #toddlerlife
...

For children or adults with severe food allergies, they can be incredibly scary and restrictive. We may imagine that it’s easy to deal with a peanut allergy by, say, not eating peanut butter sandwiches. But for someone with a severe version of this allergy, they may never be able to go to a restaurant, for fear of a severe reaction to something in the air. Right now, there’s only one approved treatment for severe allergies like this and it’s limited to peanuts.

This is why the new medication Xolair is very exciting. It promises a second possible treatment avenue and one that works for other allergens. A new trail analyzed data from 177 children with severe food allergies. Two-thirds of the treatment group were able to tolerate the specified endpoint, versus just 7% of the placebo group. This is a very large treatment effect, and the authors found similarly large impacts on other allergens. 

There are some caveats: This treatment won’t work for everyone. (One-third of participants did not respond to it.) Additionally, this treatment is an injection given every two to four weeks, indefinitely. This may make it less palatable to children. 

Overall, even with caveats, this is life-changing news for many families!

#xolair #foodallergies #allergies #peanutallergy #emilyoster #parentdata

For children or adults with severe food allergies, they can be incredibly scary and restrictive. We may imagine that it’s easy to deal with a peanut allergy by, say, not eating peanut butter sandwiches. But for someone with a severe version of this allergy, they may never be able to go to a restaurant, for fear of a severe reaction to something in the air. Right now, there’s only one approved treatment for severe allergies like this and it’s limited to peanuts.

This is why the new medication Xolair is very exciting. It promises a second possible treatment avenue and one that works for other allergens. A new trail analyzed data from 177 children with severe food allergies. Two-thirds of the treatment group were able to tolerate the specified endpoint, versus just 7% of the placebo group. This is a very large treatment effect, and the authors found similarly large impacts on other allergens.

There are some caveats: This treatment won’t work for everyone. (One-third of participants did not respond to it.) Additionally, this treatment is an injection given every two to four weeks, indefinitely. This may make it less palatable to children.

Overall, even with caveats, this is life-changing news for many families!

#xolair #foodallergies #allergies #peanutallergy #emilyoster #parentdata
...

If you have a fever during pregnancy, you should take Tylenol, both because it will make you feel better and because of concerns about fever in pregnancy (although these are also overstated).

The evidence that suggests risks to Tylenol focuses largely on more extensive exposure — say, taking it for more than 28 days during pregnancy. There is no credible evidence, even correlational, to suggest that taking it occasionally for a fever or headache would be an issue.

People take Tylenol for a reason. For many people, the choice may be between debilitating weekly migraines and regular Tylenol usage. The impacts studies suggest are very small. In making this decision, we should weigh the real, known benefit against the suggestion of this possible risk. Perhaps not everyone will come out at the same place on this, but it is crucial we give people the tools to make the choice for themselves.

#emilyoster #parentdata #tylenol #pregnancy #pregnancytips

If you have a fever during pregnancy, you should take Tylenol, both because it will make you feel better and because of concerns about fever in pregnancy (although these are also overstated).

The evidence that suggests risks to Tylenol focuses largely on more extensive exposure — say, taking it for more than 28 days during pregnancy. There is no credible evidence, even correlational, to suggest that taking it occasionally for a fever or headache would be an issue.

People take Tylenol for a reason. For many people, the choice may be between debilitating weekly migraines and regular Tylenol usage. The impacts studies suggest are very small. In making this decision, we should weigh the real, known benefit against the suggestion of this possible risk. Perhaps not everyone will come out at the same place on this, but it is crucial we give people the tools to make the choice for themselves.

#emilyoster #parentdata #tylenol #pregnancy #pregnancytips
...

Parenting trends are like Cabbage Patch Kids: they’re usually only popular because a bunch of people are using them! Most of the time, these trends are not based on new scientific research, and even if they are, that new research doesn’t reflect all of what we’ve studied before.

In the future, before hopping onto the latest trend, check the data first. Unlike Cabbage Patch Kids, parenting trends can add a lot of unnecessary stress and challenges to your plate. What’s a recent trend that you’ve been wondering about?

#parentdata #emilyoster #parentingtips #parentingadvice #parentinghacks

Parenting trends are like Cabbage Patch Kids: they’re usually only popular because a bunch of people are using them! Most of the time, these trends are not based on new scientific research, and even if they are, that new research doesn’t reflect all of what we’ve studied before.

In the future, before hopping onto the latest trend, check the data first. Unlike Cabbage Patch Kids, parenting trends can add a lot of unnecessary stress and challenges to your plate. What’s a recent trend that you’ve been wondering about?

#parentdata #emilyoster #parentingtips #parentingadvice #parentinghacks
...

As of this week, 1 million copies of my books have been sold. This feels humbling and, frankly, unbelievable. I’m so thankful to those of you who’ve read and passed along your recommendations of the books.

When I wrote Expecting Better, I had no plan for all of this — I wrote that book because I felt compelled to write it, because it was the book I wanted to read. As I’ve come out with more books, and now ParentData, I am closer to seeing what I hope we can all create. That is: a world where everyone has access to reliable data, based on causal evidence, to make informed, confident decisions that work for their families.

I’m so grateful you’re all here as a part of this, and I want to thank you! If you’ve been waiting for the right moment to sign up for full access to ParentData, this is it. ⭐️ Comment “Link” for a DM with a discount code for 20% off of a new monthly or annual subscription to ParentData! 

Thank you again for being the best community of readers and internet-friends on the planet. I am so lucky to have you all here.

#parentdata #emilyoster #expectingbetter #cribsheet #familyfirm #parentingcommunity

As of this week, 1 million copies of my books have been sold. This feels humbling and, frankly, unbelievable. I’m so thankful to those of you who’ve read and passed along your recommendations of the books.

When I wrote Expecting Better, I had no plan for all of this — I wrote that book because I felt compelled to write it, because it was the book I wanted to read. As I’ve come out with more books, and now ParentData, I am closer to seeing what I hope we can all create. That is: a world where everyone has access to reliable data, based on causal evidence, to make informed, confident decisions that work for their families.

I’m so grateful you’re all here as a part of this, and I want to thank you! If you’ve been waiting for the right moment to sign up for full access to ParentData, this is it. ⭐️ Comment “Link” for a DM with a discount code for 20% off of a new monthly or annual subscription to ParentData!

Thank you again for being the best community of readers and internet-friends on the planet. I am so lucky to have you all here.

#parentdata #emilyoster #expectingbetter #cribsheet #familyfirm #parentingcommunity
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Just eat your Cheerios and move on.

Just eat your Cheerios and move on. ...

The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide

The AAP’s guidelines recommend sleeping in the same room as your baby “ideally for the first six months.” However, the risk of SIDS is dramatically lower after four months, and the evidence in favor of the protective effect of room sharing is quite weak (both overall and even more so after four months). There is also growing evidence that infants who sleep in their own room by four months sleep better at four months, better at nine months, and even better at 30 months.

With this in mind, it’s worth asking why this recommendation continues at all — or at least why the AAP doesn’t push it back to four months. They say decreased arousals from sleep are linked to SIDS, which could mean that babies sleeping in their own room is risky. But this link is extremely indirect, and they do not show direct evidence to support it.

According to the data we have, parents should sleep in the same room as a baby for as long as it works for them! Sharing a room with a child may have negative impacts on both child and adult sleep. We should give families more help in navigating these trade-offs and making the decisions that work best for them.

#emilyoster #parentdata #roomsharing #sids #parentingguide
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