Losing weight while you sleep?

Factual Questions
1

http://www.npr.org/blogs/krulwich/2013/06/19/193556929/every-night-you-lose-more-than-a-pound-while-youre-asleep-for-the-oddest-reason?utm_source=npr&utm_medium=facebook&utm_campaign=20130621

This article claims that you breathe out a pound worth of carbon via carbon dioxide every 8 hours of sleep you get.

Is this claim credible? I assume if NPR is running it, it is, but I really wonder. Can anyone do the math on this?

Wouldn’t the H2O you’re breathing out weigh a HELL of a lot more than the C int he CO2 you’re breathing out?

2

Not credible.

See this past thread. CO2 does not magically appear.It is the product of metabolic processes. In post #25 Michael63129 did some calculating and showed that to produce 1# of CO2 you’d need to be burning through over 2700 Calories in your sleep. No, you do not respire that much in your sleep. You of course burn through some calories and lose some weight, but a fraction of that amount.

Breathing out moisture if the air is low humidity is a factor, not sure how big of one.

In post #44 I linked to a study that showed that people lose weight more in their sleep more from sweating more, specifically during slow wave sleep.

3

No it doesn’t. It claims one mechanism of several that add up to a pound is the loss of carbon. I just skimmed the video, but it sounds like the claim they make is that carbon loss adds up to about 100 grams (quarter pound).