Can You Re-warm Formula? What Are the "Rules", I Am a Formula Novice!

Updated on September 24, 2008
L.T. asks from La Mesa, CA
5 answers

Hi Ladies-
My breast milk has sadly all but dried up and we had to go onto formula, so now...I'm a little out of my element. This may seem stupid, but there doesn't seem to be any good rule of thumb to go by...except on the can, it says once prepared & kept cold, it's good for 24 hours, and that you must discard a bottle w/in one hour of feeding. Okay, I know of day-cares that push it to 2 hours and re-warm bottles that have been sucked on, and hospitals believe it or not that will still feed from a bottle w/ in 4 hours (yuck!). I really don't want to make my daughter ill, and don't really care about wasting some formula, just need to know what to do. Here's an example of my dilemma, say you prepare a warm bottle, offer it, baby won't even let it touch her lips, so do you throw it out, or put it back in fridge and use that one within 24 hours? Say she drank only 2oz, is that bottle only good for 1 or 2 hours...and can you re-warm it? Uggh...this sounds so silly to me like I should know's not rocket science! Anyway...just trying to make life a little easier for me and safer for 9 mo old baby Lily. Thanks in advance!

P.S. I'm still nursing as often as she wants...but I just don't have the volume:-( She really seems to need the milk between her solids and sips of water throughout the day. She will also take cold formula from a sippy at mealtime.

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answers from San Diego on

Hi L.,

Due to a medical issue wherein I had to be on some unresearched (for breastfeeding) drugs when I first gave birth, I was unable to breast feed. I pumped and dumped as much as I could, but ended up having to do only formula, so we too had some of the same questions when we were starting out.

I agree with the other two ladies here who posted. Specifically, we do the same as Charlotte did - we don't heat the bottles at all, we just make the bottle with room temp bottled water. Which is also a plus for when we're out and about, he's not used to heated food, so it's no big deal when he gets it at room temperature.

Yes, if you were to re-heat it after he's been drinking it, bacteria could grow. Just toss it after 24 hours if it's been in the fridge and if it's been out for more than hour, also toss it. If he's drank off of it at all, technically, you're supposed to toss it after 1 hour even if you refrigerate it, but you're right that some people don't. Again, the reason is bacteria.

As a side note, they also say not to heat formula then put it in a thermos if you're taking your baby out for the same reason - bacteria could grow inside the thermos. We usually put the scoops of formula in one bottle and the amount of water needed in another bottle, then when he gets hungry, we just quickly mix the water into the formula bottle and shake it up - good to go. You have to figure, your breast milk isn't heated, it's at about room temp, so they're used to it anyway.

Have fun!;)

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answers from San Diego on

don't feel dumb--even the pamphlets and such out there are not consistent! I don't think reheating is okay after it touched lips. I throw out unused formula if it has been sitting out for 1 hour. If it never touched her lips, you can put in in the fridge and use later (24hrs).

BTW--a mommy-to-mommy tip: I never heat the water when I mix formula and it makes life SOOOOO much EASIER! No microwaves, stoves, or stupid bottle warmers. I just got baby used to it early on. It is really nice when you are out and about, b/c you can just pre-fill the bottle with water, carry it in the diaper bag, and it's ready to go when you are (just add pre-measured formula when ready)... and not worry about temperature.

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answers from San Diego on

Hi L.,

We never kept a bottle in the fridge more than 24 hours once prepared. And if the bottle had been heated once, I would only reheat it once more after that. We actually don't initially heat the bottles either. We kept bottled water on the counter and prepare the formula with that and our son has always liked it room-temp. If he didn't finish it, we refrigerated and still would only reheat once and then discard, even if I added on top of what was in there.

By the way, your baby will need more than just ONE bottle per day. When our son was 9 months old, our Pedi recommended that he still get in at least 20oz a day. We gave him 8oz in the morning and two more 6oz feedings, one with lunch and one with dinner. In addition, of course the baby needs solids, our son eats what we eat.




answers from San Diego on

I believe it tells you on the formula containers about re-heating. As far as I know it isn't safe to re-heat.

P.S. Your milk might pick up again, so if you want to continue BF keep it up, becuase the less the baby nurses the more quickly you'll lose your milk.



answers from San Diego on

Hi Tara, I never re heat formula, or breast mild in my daycare, and I never re heated my babies formula, either, I have always had cats, so I would just give them the left over. When I had my first baby 25 years ago and Balboa Naval Hospita, which i loved and had a blast, they had training times for us first time moms, we were told that if you reuse a bottle you are feeding your baby bacteria, so to this day I don't re use or re heat formula. When my babies were 9 months they only had one bottle a day and that was a morning bottle while I was preparing their cereal, they were on a 3 meals a day plus baby snacks and their sippy cup schdule. Don't think you should know everything, asking questions just shows you want the best for Lily. Good Job Mom, J. L.

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