Can My Baby Wean Before One Year?

Emily Oster

3 min Read Emily Oster

Emily Oster

Can My Baby Wean Before One Year?

Q&A on hiding formula

Emily Oster

3 min Read

Hello, my 10-month-old is weaning off formula herself. I’ve tried hiding it in food. Switching it to an open cup and a straw cup. She just doesn’t want it anymore. She eats three full, balanced meals a day with plenty of dairy sources. Is it okay to switch to cow’s milk? She is in the 92nd percentile for weight and the 100th for height.

—Meagan

This question gets at what I think is a deep and confusing space: the transition away from formula or breast milk at one year. There is a standard message. First: that your child should use formula through a year and then switch to milk. Second: that you should breastfeed for a year but if you want to continue doing so after a year, that’s great.

The messaging invites two questions. First: why does formula use end at a year and breast milk does not? And second, why exactly a year?

To the first question: By a year, most kids are getting a lot of their nutrition through solid food sources, regardless of whether they were using formula or breast milk. This makes either of these less important as a food source. But since breastfeeding for an extended period is something people do for many reasons, there are reasons they might want to continue even as it becomes less important as a food source. In contrast, formula is only a food source, so there isn’t really any reason to continue using it past where its food value is higher.

To the second question: Nothing in medicine has a cutoff like this. There is no magical moment at 12 months when children switch from needing formula to needing cow’s milk. The most important nutrient difference at this time is iron — formula has more than cow’s milk, and for a kid who is consuming formula as a huge share of their calories, switching that all to milk before they are consuming a lot of solid food could lead to iron deficiency. (Cow’s milk also has more protein and calcium, which is useful for a toddler.)

It sounds like this is not the situation you are in, if your child is eating three solid food meals a day. In this case, moving away from formula could make sense. This is an example of something you should discuss with your pediatrician before doing anything rash! There may be a desire to introduce some supplements, or target the diet, to make sure your child is getting their iron and other nutrient needs met.

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I’m calling on you today to share your story. I know that many of you have experienced complications during pregnancy, birth, or postpartum. It’s not something we want to talk about, but it’s important that we do. Not just for awareness, but to help people going through it feel a little less alone.

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OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio!

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio!

OUT NOW: My new book “The Unexpected: Navigating Pregnancy During and After Complications” is available on April 30th. All of my other books came out of my own experiences. I wrote them to answer questions I had, as a pregnant woman and then as a new parent. “The Unexpected” is a book not to answer my own questions but to answer yours. Specifically, to answer the thousands of questions I’ve gotten over the past decade from people whose pregnancies were more complicated than they had expected. This is for you. 💛 Order now at my link in bio! ...

Is side sleeping important during pregnancy? Comment “Link” for a DM to an article on whether sleep position affects pregnancy outcomes.

Being pregnant makes you tired, and as time goes by, it gets increasingly hard to get comfortable. You were probably instructed to sleep on your side and not your back, but it turns out that advice is not based on very good data.

We now have much better data on this, and the bulk of the evidence seems to reject the link between sleep position and stillbirth or other negative outcomes. So go ahead and get some sleep however you are most comfortable. 💤

Sources:
📖 #ExpectingBetter pp. 160-163
📈 Robert M. Silver et al., “Prospective Evaluation of Maternal Sleep Position Through 30 Weeks of Gestation and Adverse Pregnancy Outcomes,” Obstetrics and Gynecology 134, no. 4 (2019): 667–76. 

#emilyoster #pregnancy #pregnancytips #sleepingposition #pregnantlife

Is side sleeping important during pregnancy? Comment “Link” for a DM to an article on whether sleep position affects pregnancy outcomes.

Being pregnant makes you tired, and as time goes by, it gets increasingly hard to get comfortable. You were probably instructed to sleep on your side and not your back, but it turns out that advice is not based on very good data.

We now have much better data on this, and the bulk of the evidence seems to reject the link between sleep position and stillbirth or other negative outcomes. So go ahead and get some sleep however you are most comfortable. 💤

Sources:
📖 #ExpectingBetter pp. 160-163
📈 Robert M. Silver et al., “Prospective Evaluation of Maternal Sleep Position Through 30 Weeks of Gestation and Adverse Pregnancy Outcomes,” Obstetrics and Gynecology 134, no. 4 (2019): 667–76.

#emilyoster #pregnancy #pregnancytips #sleepingposition #pregnantlife
...

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I co-wrote #TheUnexpected with my friend and maternal fetal medicine specialist, Dr. Nathan Fox. The unfortunate reality is that about half of pregnancies include complications such as preeclampsia, miscarriage, preterm birth, and postpartum depression. Because these are things not talked about enough, it can not only be an isolating experience, but it can also make treatment harder to access.

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My new book, “The Unexpected: Navigating Pregnancy During and After Complications” is available for preorder at the link in my bio!

I co-wrote #TheUnexpected with my friend and maternal fetal medicine specialist, Dr. Nathan Fox. The unfortunate reality is that about half of pregnancies include complications such as preeclampsia, miscarriage, preterm birth, and postpartum depression. Because these are things not talked about enough, it can not only be an isolating experience, but it can also make treatment harder to access.

The book lays out the data on recurrence and delves into treatment options shown to lower risk for these conditions in subsequent pregnancies. It also guides you through how to have productive conversations and make shared decisions with your doctor. I hope none of you need this book, but if you do, it’ll be here for you 💛

#pregnancy #pregnancycomplications #pregnancyjourney #preeclampsiaawareness #postpartumjourney #emilyoster
...

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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. 💙
...

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.

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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
...

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

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
...

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.

#perimenopause #perimenopausehealth #womenshealth #hormoneimbalance #emilyoster #parentdata
...

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

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
...

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

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
...

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

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
...

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

#funnytweets #bedtime #nightimeroutine #parentinghumor #parentingmemes

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

#funnytweets #bedtime #nightimeroutine #parentinghumor #parentingmemes
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