when is 6oz not 6oz? Baby formula measuring.

November 6, 2009 5:31 AM

How do you measure how much formula your infant is eating?

This sounds like a silly question, I know, but I'm confused.

I make my daughter's bottles as she needs them. As explained on the formula container, I mix one scoop of formula for two ounces of water. I put 6 oz of water in the bottle, add three scoops and mix. When I'm done, the bottle contains more than 7 oz.

I have a friend who mixes all her formula in advance. So she puts 30 oz of water in a container, adds 15 scoops of formula, and mixes. When she wants to feed her baby 6 oz, she pours 6 oz of formula into the bottle.

We both say our babies are eating 6 oz. My theory is that she is getting 6 oz worth of the powder, so 6 oz worth of calories. Her theory is she's drinking 6 oz of liquid, so, that's 6 oz.

I realize it doesn't really matter as long as I'm consistent, and that I should ask my pediatrician. But I'd like to know how other people measure, or think it should be measured, or what they believe logically makes sense (or if there is an actual right answer, that would be great, but I have no idea where to find it!)

posted by dpx.mfx to food & drink (12 comments total)

Definitely measure what she consumes in ounces, not the "ounces worth of powder" that she consumes.

What's relevant is how much "formula" she's getting, not how much "powder". Formula is the stuff you end up after you've mixed the powder with the water.

And, frankly, it can make a big difference. I make it in batches these days because she's eating so much, so I will pour a bottle of 6oz exactly. But back when I was making it one bottle at a time, I would definitely check the level once I'd finished mixing. And I think that 6oz becomes almost 7oz when mixed. If you have 5 or 6 feeds a day and she's finishing all of those bottles, that's an extra feed's worth of formula. Definitely relevant.

I'm fairly confident that this is the right answer, by the way. :)
posted by HopStopDon'tShop at 5:48 AM on November 6, 2009

what they believe logically makes sense.

My daughter will be a year old in about a week. She stopped nursing at 8 months, and got formula as a supplement ranging from almost none when she was small to most of her nutrition before she was weaned. We always counted the amount with the prescribed amount from the formula directions: as in, "the formula package says two scoops makes four ounces, we added two scoops to four ounces of water, baby drank that, so she had four ounces despite the fact that it was slightly more than that after it was prepared."

You should err on the conservative side because you're trying to make sure she gets enough formula. But here's the advice from a still-new parent who just went through what you are now: Don't worry about it too much. If your baby is noticeably not drinking, seems off and is making super-concentrated brown pee, then you need to talk to your doctor. But the difference between baby drinking 18 ounces of formula versus 21 is not going to interest your doctor.

I say this because my daughter went through a period of diminished intake at around four months, and we were mildly worried about it. We mentioned it at a checkup, said that we were struggling to get the recommended amount in her, and our doctor asked if she had difficulty swallowing or GI distress. We said that she didn't, and she (the doctor) said that's fine and nonchalantly asked us an unrelated question. It's natural to get hung up on everything as new parent, but if the baby seems comfortable it's fine. Keep track, certainly, but don't freak out if some days your baby doesn't want much. If we were to have another kid, we'd worry so much less having been through it once.
posted by Mayor Curley at 6:00 AM on November 6, 2009

I just went through this. Don't get to freaked out about it. Sometimes babies drink more, sometimes less. Just monitor to make sure it's fairly consistent. The doctor is checking at each visit to make sure the baby is gaining weight.
posted by kenliu at 6:10 AM on November 6, 2009 [1 favorite]

I see that I read your question wrong, my bad. What other people say, I guess: the difference between a 7 oz bottle or a 6 oz bottle wouldn't matter too much, as long as you yourself know which method you're using and as long as your kid gets enough to eat.

As a data point: I measure 8 oz of water and then add the required amount of formula for 8 oz., so I use your method instead of your friend's. I guess most people do it that way.
posted by NekulturnY at 6:24 AM on November 6, 2009

I think the "extra" ounce you get when you make one bottle at a time is mostly air. You shake the bottle quite hard to get it mixed and that foams it up (some of it visible as actual foam on top, but much of is simply throughout the bottle). The powder is very fine, and dissolves easily, so I don't think it's adding an ounce of volume to the water the way a rock would if you dropped it in. It's not clear if you're asking because you're concerned or just curious, but as others have said, it's no big deal if you're worrying about it.
posted by cocoagirl at 6:27 AM on November 6, 2009 [1 favorite]

When I add three scoops of formula powder to 6 oz of water, the result appears to me as 6.5 oz of formula. If baby drinks it all, she just drank 6.5 oz.

Mayor Curley and kenliu are right tho - the numbers are insignificant. Is your baby eating, peeing, pooing and acting healthy? Then she's fine.
posted by gnutron at 6:52 AM on November 6, 2009

I'm also in the "don't worry about the measurement" camp. If there's input, output, and happiness then you're doing OK. I only measured with my son for bragging rights/astonishment as the the little guy was taking bottles that, if you scaled up the volume based on the proportion of his mass to an adult, would be equivalent to an adult drinking a gallon of milk in under 15 minutes.
posted by plinth at 8:15 AM on November 6, 2009

Since when do babies know that each feeding must consist of exactly six ounces? Ours sometimes wanted more than one bottle at a feeding, sometimes less, which made the whole question of precision measurement completely moot.

Babies want food when they're hungry, and they stop eating when they're full: if you mix it a bit thicker they will drink less; if you mix it a bit thinner they'll ask for more.

It doesn't matter even if you're inconsistent about how you measure. My wife and I discovered late in the game that we were mixing it differently: I tended to put in formula first and then top off with water; she did it the other way around. I don't recall which of us was correctly following the instructions on the box, but I don't think it matters at all.

(I even speculate that a little variation in the bottle -- we didn't stick to a single formula brand, and for complicated logistical reasons even switched back and forth between formula and frozen breast milk at one point -- is what helped him be a not-at-all picky eater later on. Sample size of this study = 1; results inconclusive. More funding obviously required)

Close enough is close enough.
posted by ook at 8:43 AM on November 6, 2009

To be clear, I'm not worried in the sense that I don't think she's getting enough to eat -- she gets plenty of formula and now solids, too. But when the doctor says "how much does she eat" (approximately), I multiply the number of bottles times 6 (or it used to be five). And when my friend who measures the other way and I compare how much our kids -- who are a week apart -- are eating, we just realized we are talking about two different things.

Ook, my husband used to also add the formula first, then the water. The box says to do it the other way, and we found that if you add too much formula without enough water, we had gas/constipation issues. Took us a while to figure out what it was -- she only seemed that way during the week (when he was feeding her all her bottles) and not on the weekends (when I was). Other than that we've been blessed with a baby who seems to eat anything - breast milk, formula, baby food, people food -- in whatever vessel we serve it -- breast, any kind of bottle, spoons, fingers. I know it isn't that easy for everyone, so I feel especially blessed.
posted by dpx.mfx at 10:04 AM on November 6, 2009

we found that if you add too much formula without enough water, we had gas/constipation issues.

Interesting. I'm surprised it made that much of a difference -- it didn't seem to for us. I guess that's the problem with sample size = 1...
posted by ook at 11:46 AM on November 6, 2009

A breastfeeding mother has no clue how much her child is getting in a feeding. Why the amount in a feeding important (to you or your doctor)? A healthy, thriving child is all the measurement you need.
posted by Joleta at 7:46 PM on November 6, 2009

I think when the doctor asks about how much your baby is eating, it's just to check whether it is in a normal range, and probably also to force you to think about it. The doctor isn't going to know how much food your particular baby needs, but she is familiar with what is typical for babies at a given age.
posted by kenliu at 9:46 PM on November 7, 2009