Eating for 2 after all...

Oishii

I've been reading some interesting research that suggests our 9 month pregnancies are linked to our metabolisms. Basically, we give birth once our metabolisms can no longer process enough calories to supply both baby and mother:


http://blogs.smithsonianmag.com/hominids/2012/08/timing-of-childbirth-evolved-to-match-womens-energy-limits/

The figure quoted is 2-2.5 x BMR. So, by the time you give birth you really may be able to 'eat for two' without gaining excess weight.

This may explain why my weight shot up for 6 months but has been in a month-long plateau: even if I eat as much, it just gets used up!

Rubyayn

What a neat article!! A lot of that makes sense.

igottaworkout

That article seems faulty..

- historically childbirth has always been dangerous, not just in 'modern times'
- what about people who have multiples? They have an even higher caloric requirement
- women are still the source of all energy for the baby because of breastfeeding which increases as the baby gets larger
- saying that natural selection has not had enough time to widen women's pelvis to account for larger babies (which is also speculation to say babies are larger now because of lack of historical data) is stupid because our medical intervention allows women to survive that would have died off through natural selection, so that will never happen unless they start letting women die during birth
- not to mention that it would be easy to gain more weight as the pregnancy goes on.. as most people do and many carry into 10 months still gaining weight and increasing energy output. I lost a lb just before birth probably because the body cleans out the bowels just before birth which doesn't say that my body couldn't keep gaining more weight.

I hate articles that have so many errors of logic and are spouted as 'science'

Oishii

That article seems faulty..

- historically childbirth has always been dangerous, not just in 'modern times'

What does this have to do with the article? Childbirth is difficult for humans in comparison to other animals, which is what the research is about. That is the interesting contrast.

- what about people who have multiples? They have an even higher caloric requirement

Which is why twins are usually born smaller and earlier.

- women are still the source of all energy for the baby because of breastfeeding which increases as the baby gets larger

The research doesn't touch on this at all. A number of people see a contradiction here, but I don't see why.

- saying that natural selection has not had enough time to widen women's pelvis to account for larger babies (which is also speculation to say babies are larger now because of lack of historical data) is stupid because our medical intervention allows women to survive that would have died off through natural selection, so that will never happen unless they start letting women die during birth

I don't think I saw this in the article, and certainly not in the research. Maybe I chose a poor article (I wanted one with the BMR reference which isn't in the press release or abstract).

- not to mention that it would be easy to gain more weight as the pregnancy goes on.. as most people do and many carry into 10 months still gaining weight and increasing energy output. I lost a lb just before birth probably because the body cleans out the bowels just before birth which doesn't say that my body couldn't keep gaining more weight.

What your body can't usefully metabolise will be turned to fat. This research is about human evolution, not weight gain in pregnancy.

I hate articles that have so many errors of logic and are spouted as 'science'

I'll have to reread it. My refutations are based on the content of the research, not this particular article. What I do when bad science grates on me is look for the source they used and see what I think of that instead. I'll post those later.

Oishii

I Reread the article and I can see that you might find the last paragraph annoying, but that was not the core of the research. Also 'relatively recently' in evolutionary terms does not equate to 'modern times'.i suspect that last paragraph was a journalist trying to round off an article as I haven't seen it in any of the other articles on it.

igottaworkout

I don't think you got my point.. I'm not trying to attack you. That article is written very badly and with bad research/conclusions and not thought out well. If the research doesn't address something essential that can negate all of their findings that means it is pretty much pointless.

Just think about it.. some people can be 400lb+ and still support their energy requirements. I'm 143lb at 38 weeks and could certainly keep growing up to 400lb without my body running out of energy (although of course I don't want to and watch what I eat). Obviously something else triggers birth, perhaps the placenta starts to degenerate or something else entirely.

Oishii

I don't think you got my point.. I'm not trying to attack you. That article is written very badly and with bad research/conclusions and not thought out well. If the research doesn't address something essential that can negate all of their findings that means it is pretty much pointless.

Just think about it.. some people can be 400lb+ and still support their energy requirements. I'm 143lb at 38 weeks and could certainly keep growing up to 400lb without my body running out of energy (although of course I don't want to and watch what I eat). Obviously something else triggers birth, perhaps the placenta starts to degenerate or something else entirely.

A lot of very big people have very big problems getting pregnant and getting through a pregnancy, so I don't think that's a valid argument against the research. Personally, I find the research quite convincing and don't see the holes you think you see. Ignore the last paragraph, and I think it's a fairly fair representation of an interesting piece of research.

What it is saying is that a pregnant body can only metabolise (ie, turn into energy) 2-2.5 times its normal BMR (which should be higher the heavier you are), and that by the end of 9 months, to support a growing baby, that maximum number of calories you are capable of processing is exceeded. Her methods seem pretty solid to me, as does the science, and I still can't see how you think anything you have written contradicts the essence of this research.

Of course you can eat more than you can metabolise and this will turn into fat and be stored to use later.