# Microwaving breast milk: bad?
**URL:** https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366
**Category:** Factual Questions
**Created:** [February 2, 2003, 9:31pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366 "2003-02-02T21:31:52Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@nogginhead](https://boards.straightdope.com/u/nogginhead)
#### Post date: [February 2, 2003, 9:31pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/1 "2003-02-02T21:31:52Z")
All of the material I’ve seen on freezing breast milk (from pump manufacturers, pediatricians, etc.) say that you should never microwave breast milk to thaw it.
One very plausible reason they give is that there may be hot spots in the milk.
They also claim that microwaving will somehow diminish the nutritive value of the milk. Is this possible?
Does anyone know the dope on this?
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### Author:  [@SC\_Wolf](https://boards.straightdope.com/u/SC_Wolf)
#### Post date: [February 2, 2003, 10:22pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/2 "2003-02-02T22:22:57Z")
I can say without fear of contridiction that this practice is certainly frowned upon when the milk is still in its original container.
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### Author:  [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)
#### Post date: [February 2, 2003, 10:43pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/3 "2003-02-02T22:43:14Z")
Microwaves are known to break down complex molecules, which is why things like tea don’t taste quite so good when heated in a microwave. I doubt that a whole lot of research has been done on the subject, but generally with all things baby related everyone takes the better safe than sorry approach.
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### Author:  [@Mangetout](https://boards.straightdope.com/u/Mangetout)
#### Post date: [February 2, 2003, 10:48pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/4 "2003-02-02T22:48:15Z")
I believe that there was a case in a newborn intensive care unit where expressed milk was being _kept warm_ in a microwave heater, but the babies did not flourish; IIRC it was discovered that some of the complex lipids and proteins were being broken down by prolonged exposure.
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### Author:  [@MsRobyn](https://boards.straightdope.com/u/MsRobyn)
#### Post date: [February 3, 2003, 1:28am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/5 "2003-02-03T01:28:15Z")
Microwaving food in general will diminish the nutritive value somewhat.
It is Very Bad to microwave food for babies. Nutrients break down (as has already been said), and more important, microwave ovens can make food very hot very quickly. Babies have been burned very badly from this. The best way to thaw stored breastmilk or formula is to place it in warm (not hot) water until it’s at an appropriate temperature. I keep a pot on the stove with water; when Aaron is ready to eat, I put the bottle in the water, turn the stove on, and heat the water until it’s at a good temperature, then turn the stove off and let the bottle finish heating. I’ve yet to make a bottle that was too hot for him.
Jarred foods can be heated in the microwave, but it takes no more than 20 seconds, max. More time than that renders the food too hot to eat. Timing is critical; I heated a jar of food yesterday for 25 seconds, and it was too hot.
Robin
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### Author:  [@Primaflora](https://boards.straightdope.com/u/Primaflora)
#### Post date: [February 3, 2003, 1:34am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/6 "2003-02-03T01:34:14Z")
[http://www.lalecheleague.org/FAQ/microwave.html](http://www.lalecheleague.org/FAQ/microwave.html)
has all the info you need
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### Author:  [@nogginhead](https://boards.straightdope.com/u/nogginhead)
#### Post date: [February 3, 2003, 3:57am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/7 "2003-02-03T03:57:04Z")
I guess I wasn’t clear enough in the OP. I recognize that hot spots can be a problem.
I’m looking for **scientific reasons** , not regurgitations, about why microwaving is bad in terms of nutritive value. Thank you especially, engineer\_comp\_geek and mangetout.
Here’s what the helpful link to the la leche league has to say:
> [@](#):
>
> Can human milk be heated in the microwave?
>
> “Human milk should not be heated in a microwave oven” states LLLI’s BREASTFEEDING ANSWER BOOK, Revised Edition, 1997 on page 191. Warming your stored milk in the microwave causes it to heat unevenly, creating “hot spots” that may burn your baby’s mouth. Furthermore, valuable immunological components will be destroyed.
>
> Frozen or refrigerated human milk is best heated under cool then warm running water. If running water is not available, a pan of water can be heated on the stove. The container of milk can be placed in the warm water once it has been removed from the heat source. The milk should not be heated directly on the stove.
Do they think that people can’t understand what, exactly, will happen?
The only useful thing here is “Furthermore, valuable mmunological components will be destroyed.” (Since anyone can figure out how to make sure there are no hot spots.) Though of course there are no cites for this claim, which is common to all claims of this nature I have seen. In keeping with the aim of the board, I am trying to avoid received wisdom in preference for actual facts.
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### Author:  [@Primaflora](https://boards.straightdope.com/u/Primaflora)
#### Post date: [February 3, 2003, 4:09am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/8 "2003-02-03T04:09:57Z")
Why, yes Nogginhead, they do think that people do not realise that hot spots occur because, geez, well, it does occur and babies do get burned so they do think it’s worth mentioning.
I’m so sorry that I bothered to look up that page for you and I’m so sorry that in response to your less than clear OP, you didn’t receive the precise, exact information which you seek. However I have a solution for my role in this and that solution is to cease looking for the information you want. It is out there, there are places you can ask but I won’t be bothering. Chances are if I go and search lactnet for you you’d just say something about received wisdom anyway.
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### Author:  [@China\_Guy](https://boards.straightdope.com/u/China_Guy)
#### Post date: [February 3, 2003, 8:27am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/9 "2003-02-03T08:27:57Z")
Well, you’re not supposed to heat formula in a microwave either as it breaks down some of the nutritive effects. Sorry no cites.
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### Author:  [@Mangetout](https://boards.straightdope.com/u/Mangetout)
#### Post date: [February 3, 2003, 8:43am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/10 "2003-02-03T08:43:48Z")
Here’s a [link](http://boards.straightdope.com/sdmb/showthread.php?&threadid=140182) to a previous discussion of the topic (which contains the story I was recalling, but alas there is still no cite for it.)
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### Author:  [@Mangetout](https://boards.straightdope.com/u/Mangetout)
#### Post date: [February 3, 2003, 9:00am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/11 "2003-02-03T09:00:40Z")
I must admit, I’m skeptical about the story of breast milk being maintained at body temperature - it is impossible that the milk would be aseptically collected and stored, so keeping it warm would provide the ideal conditions for bacterial growth.
(Mmmmm…breast milk yoghurt)
**nogginhead** : you might like to try adding **SITE:.ac.uk** or **SITE:.edu** to your google searches on the subject - this should limit the search to academic sites.
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### Author:  [@diffdam](https://boards.straightdope.com/u/diffdam)
#### Post date: [February 3, 2003, 11:53am UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/12 "2003-02-03T11:53:31Z")
Microwaving is well known to destroy vitamins & useful proteins, can cause “off” flavours if used for meat.It really is very unsuitable for such a delicate mixture.
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### Author:  [@Mangetout](https://boards.straightdope.com/u/Mangetout)
#### Post date: [February 3, 2003, 12:01pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/13 "2003-02-03T12:01:51Z")
What I think would be useful to know is whether this (alleged) degradation in nutrient value is caused by local superheating or by the microwave emissions disrupting complex molecules more directly.
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### Author:  [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)
#### Post date: [February 3, 2003, 12:10pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/14 "2003-02-03T12:10:26Z")
> [@](#):
>
> I’m looking for scientific reasons, not regurgitations
_Never_ say _regurgitations_ when talking about milk, breast or otherwise…
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### Author:  [@Pleonast](https://boards.straightdope.com/u/Pleonast)
#### Post date: [February 3, 2003, 1:36pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/15 "2003-02-03T13:36:01Z")
I seem to remember that one of the components of breast milk is living immunological cells. Microwaving will kill these live cells. I did a quick Google search and found these sites/cites: [FamilyResource.com](http://www.familyresource.com/health/16/285/) and [Yale-New Haven Hospital](http://www.ynhh.org/maternity/breastfeeding/pumps.html).
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### Author:  [@nogginhead](https://boards.straightdope.com/u/nogginhead)
#### Post date: [February 3, 2003, 2:17pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/16 "2003-02-03T14:17:06Z")
> [@](#):
>
> \*Originally posted by diffdam \*
> \*\*Microwaving is well known to destroy vitamins & useful proteins, can cause “off” flavours if used for meat.It really is very unsuitable for such a delicate mixture. \*\*
Got a cite for this? It would be very helpful.
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### Author:  [@nogginhead](https://boards.straightdope.com/u/nogginhead)
#### Post date: [February 3, 2003, 2:18pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/17 "2003-02-03T14:18:29Z")
> [@](#):
>
> \*Originally posted by CalMeacham \*
> \*\*_Never_ say _regurgitations_ when talking about milk, breast or otherwise… \*\*
If only you’d seen the massive projectile spit-up my 6-week-old launched yesterday… no wonder it was the first word that came to mind.
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### Author:  [@Mr.Moto](https://boards.straightdope.com/u/Mr.Moto)
#### Post date: [February 3, 2003, 2:19pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/18 "2003-02-03T14:19:52Z")
We just heat water in the nuker and warm the formula/breast milk in it. Or we use a bottle warmer, which works much faster.
Before the anti-formula nazis strike, let me point out that we had premature twins.
The twins are doing great, btw.
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### Author:  [@nogginhead](https://boards.straightdope.com/u/nogginhead)
#### Post date: [February 3, 2003, 2:40pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/19 "2003-02-03T14:40:15Z")
Congratulations on the twins and best wishes for their continued health.
But don’t expect to escape the well-intentioned do-gooding.
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### Author:  [@manwithaplan](https://boards.straightdope.com/u/manwithaplan)
#### Post date: [February 3, 2003, 4:34pm UTC](https://boards.straightdope.com/t/microwaving-breast-milk-bad/152366/20 "2003-02-03T16:34:01Z")
Our little one was breast-fed until she was about four months and my wife returned to work. She has been fed formula since (she is now eight months old) and up to very recently, we heated it in a pot of warm water. In the last few weeks we have been heating the formula in the microwave (while being very careful to avoid hot spots) and have done likewise with her mushy potatoes/veg/fish/meat. Is there evidence that this is less nutritious for her? If so, I would be happy to revert to heating her formula in a pot but it is incredibly convenient to make up batches of food for her and freeze them in ice cube trays to be heated up in the microwave.
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