Why can't breast-fed babies gain too much weight?

[escher]

I've read over and over that an exclusively breast-fed baby can't gain too much weight or get too much milk. Why is that true? I've heard (in Penelope Leach's Your Baby and Child) that babies whose moms have a large milk supply sometimes gain weight faster (but she says they won't gain more weight than is healthy). Why could it not be that they would get too much milk?

(Back story: My five week old nursling is a big baby and growing fast, I have a large milk supply, and I wonder if he is getting too much milk from me.)

Thank you!

[LindyGirl]

It's for a couple of reasons. The first is that babies must actively nurse to the degree that they're hungry, as opposed to bottle feeding, where a baby passively receives milk continuously, regardless of whether they're still hungry.

Babies alter the way they suck on the breast based on their need. Sometimes, when they're hungry, they suck long and hard to get as much milk as possible. When their bellies are full and they're almost asleep, they nurse in a shallow, tongue-fluttering way.

Also, your body makes different kinds of milk. The milk at the front of the breast has a higher water content for quenching thirst, while the hind milk is higher in fat and is more satiating. Your body adjusts the formula of milk based on information it gets from your baby's saliva -- it can produce antibodies against illness, etc. And milk changes as the baby gets older, too.

[Megan73]

What did he weigh at birth and how much does he weigh now? Is your doctor suggesting he's "overweight"?
It's totally normal for breastfed babies to gain fast. The typical BF baby doubles birthweight between three and four months then weight gain levels off. The average FF baby doesn't double birthweight until six months but keeps gaining at the same rate. That's why BF babies appear to "fall off" standard growth charts designed for FF babies.

[LindyGirl]

I forgot to mention: my first baby was very big (and I did not have a super abundant milk supply). He was consistently in the 140th percentile on the growth chart, super chubby, and exclusively breastfed. My doctor was always pleased that he was so roly-poly, and would take him around to the nurses saying, "See? THIS is what an EBF baby looks like!" (My second was a skinny baby and nursed even more than my first, so I just chalked their body differences to genetics. Both are normal, as long as they're growing steadily.)

[escher]

Thanks for the responses. I hadn't really realized that it is normal for breast-fed babies to gain faster at first then to level off. That's helpful to know.

Our baby was 8 pounds 7 ounces at birth, lost 10% of his weight while in the hospital, and was up to 10 pounds 3 ounces at three weeks. His pediatrician thought he was perfectly fine then. We haven't weighed him since then, but he is clearly still growing since he is outgrowing many of his clothes!

LindyGirl: But what if my breasts give him milk (in a fast drip) even if he isn't actively sucking? Couldn't he then get more milk than he needs? He does regularly spit up, and my midwife says he is spitting up the excess that he doesn't need. But if he can passively get milk from me, it seems like it could be similar to how bottle-fed babies can be overfed. What do you think?

[LindyGirl]

But see, if a baby's tummy is uncomfortably full, it will latch off and/or spit up. Babies are instinctive nursers, which means they're not like adults who overeat for emotional issues or other reasons. When they've had enough, they stop.

I think you can cross this off your list of things to worry about. A baby who's growing well is a good thing! :)

[wishin'&hopin']

Our guy was 7 pounds 12 ounces at birth and never lost any weight and I had oversupply and he was an avid nurser...he gained quickly and at 4 months was in the 95thish percentiles for height and weight.  Then at about 6 months his growth slowed considerably and by 9 months he found his true growth curve, 50th (weight) and 75th (height) percentiles--where he has stayed.  Breast fed babies "tend" to grow quickly and as their needs change breast milk composition and the manner in which they nurse changes...so my still in the 50th/75th percentile nursling (19 months) who nurses around 5 times a day and is a fairly avid eater of solids really did grow fast at first but then slowed WAY down.  

[BabySmurf]

believe me, if a baby doesn't want milk, he won't drink it.  i don't have time to find the link right now, but normal breastfeeding patterns in infants are to nurse very frequently - my DS was most definitely latched more than unlatched during the first few months (having a sling GREATLY improved my ability to do anything rather than just sit and nurse....although I did my fair share of that).

remember that nature is smart, and that our bodies adapt to the cues that we are getting and babies are constantly giving cues.  if you are pumping you will notice that sometimes your milk will be very watery, and other times it will be very creamy, and others in between.  the consistency changes to fit a baby's needs - both during the day and through out each feeding.  If your baby is gaining well, then you don't have anything to worry about.

like a pp, my baby only lost 4 ounces when we took him home from the hospital, and grew off the charts very quickly.  he didn't even "level off" by six months, and is now 29.5lbs at one.   doctor is very pleased. 

[Megan73]

Honestly, the weight gain you describe doesn't seem extraordinary. Nor is being overfull the only reason babies spit up. I would cross this off your list of things too worry about, too!
Here's a good link from kellymom:
http://www.kellymom.com/babyconcerns/growth/weight-toomuch.html