FOUND IT!!!! Better calorie recommendations for pregnant women!

MamaBirdBoss

Okay, so I knew that the calories-by-trimester numbers that American women were being given were being pulled out of people's rear ends and were, in fact, contributing to women gaining TOO MUCH WEIGHT in pregnancy because they're too high in the second trimester and impossibly low by the end of the third. I found a study that explained, in fact, that American women who gain too much start to do so in the second trimester (maybe because some idiot told them to eat the same amount in the 2nd trimester as in the 3rd???). But I couldn't find the weight and calorie recommendations that actually have good data.

Well, now I did! They're from the WHO/FAO.

Takeaways:

-Healthy weight women should gain 24 to 31lbs (10 to 14kg), aiming for the middle amount.
-In the first trimester, women who gain a total of 12kg during pregnancy eat 20 calories extra on average a day.
-In the second, they eat 85 calories extra.
-In the third, they eat 350 calories extra.

-These are AVERAGE amounts, so at the beginning of each trimester, they're eating less than that, and at the end, more. (This is why the 300 calories a day guideline is BAD--no healthy-weight mother can healthily stick to that at the end of the of a pregnancy! Everyone eats more than that because the baby is growing fast and demands more!)

-Women's weight gain is most important during the 20th-28th weeks for avoiding underweight babies and premature birth--which means that women need to start measurably gaining by the 20th week to support the baby's growth.

http://www.fao.org/docrep/007/y5686e/y5686e0a.htm#bm10.1

If I can, I'd like to chase down a few more data points on the curve of nutrient increase--end of each trimester would be ideal.

pollypocket1021

This is awesome. Thank you.

MamaBirdBoss

Oh, and I hope it's obvious why telling women they should eat exactly 300 cal a day extra throughout the 2nd and 3rd trimester is completely nonsensical. But in case it's not...

You would gain weight, but your weight gain would gradually slow in the second to third trimester, whereas what it should do is either stay steady in the second to third trimester or even increase a little from the second half of the second, particularly, and into the third.

So let's start with a woman, 5'6", 130lbs. Her BMR is 13001.

She eats 300 calories above original maintenance a day until she reaches 140lbs. NOW, though, her BMR is 13047.

So that would mean that her weight gain would be nearly a sixth SLOWER than it was when she started gaining weight! That's not right!

So she keeps eating exactly 300 calories more and eventually reaches a 20lb weight gain. Then her BMR would be 1,392--nearly a THIRD less than what would be needed to gain weight at the same speed!

And that seriously understates the problem because it assumes she's lying unconscious, not moving her greater mass around.

The recommendations come from people who don't math. :P

What happens, then, is that women gain too fast to start with...and then biology kicks in and tells them that they're MORE hungry later, and then the whole thing turns into a snowballing mess.