This just makes me think that one of the main source of global warming is human population ( as co2 producers).
Exhaled CO2 is in equilibrium with plants inhaling CO2 to provide us food, so exhaling isn't considered a factor in global warming.
When we lose weight, where does it go?
91–100 of 131 posts
Re: When we lose weight, where does it go?
#92Earlier quoted context omitted.
> unfortunately it's water containing a bunch of heavy metals and other nasty stuff, which usually ends up flushed into the municipal sanitary sewer. Probably still better than it going up the chimney and into the atmosphere, but it would be nice if there was a way to capture and isolate those pollutants in that relatively concentrated state, before they end up mixed in with everyone's bathtub water. You can't be cla…
It would be nice if treatment plants did that.
Treatment plants in general obviously do do that.
Re: When we lose weight, where does it go?
#93Earlier quoted context omitted.
> But the most basic, predominate mechanism is that you're literally burning carbon and exhaling CO2. Well, again, you're burning oil (or if you're starving, meat), not carbon. It's mostly carbon by mass, but not by molarity.
That's not a more accurate representation than "burning carbon". The specifics are irrelevant and can sometimes even obscure basic relationships. The point is recognizing the relationship to more familiar forms of combustion and oxidation in day-to-day life; that's how you orient yourself when you come to the question for the first time. My middle school biology class would have been in the early 1990s when many of t…
> The specifics are irrelevant and can sometimes even obscure basic relationships. The point is recognizing the relationship to more familiar forms of combustion and oxidation in day-to-day life; that's how you orient yourself when you come to the question for the first time.
I would guess that there are two familiar forms of combustion in day-to-day life: burning wood, and burning gasoline. Only the second is referred to as "combustion" in the vernacular. (Since it happens in an "internal combustion engine".)
Neither involves burning pure carbon; one burns carbohydrates and one burns petroleum. The definition of "combustion" that I was taught in chemistry class was "any reaction that produces carbon dioxide and water".
But you might have a very different day-to-day life and chemistry education, I guess.
Re: When we lose weight, where does it go?
#94This just makes me think that one of the main source of global warming is human population ( as co2 producers).
The TED talk that is linked in other comments debunks this too. All the CO2 exhaled by humans is short-term carbon that was recently taken out of the atmosphere by a plant. All plants and animals are short-term carbon sinks. The damage is caused by burning fossil fuels.
I suppose there might be a few artificial ingredients that are made from petroleum feedstock, and thus human metabolism cause it's first release as CO2, but it's tiny compared to the sugars and fats we consume from plants and animals.
Re: When we lose weight, where does it go?
#95Re: When we lose weight, where does it go?
#96Likewise, where does that tree in your backyard come from? It is the product of carbon dioxide and water. edit: The significance of this thought is when a child is asked where a tree or plant comes from, at least in the US, they inevitably answer the ground when the answer should be rain that falls from the sky and air. With the naive notion a tree comes from the ground we miss the obvious which is the ground doesn't…
Veritasium has an entertaining video on this [1]. Trees get weirder and weirder every time I think about them.
Re: When we lose weight, where does it go?
#97https://www.bmj.com/content/349/bmj.g7257 Meerman, R., & Brown, A. J. (2014). When somebody loses weight, where does the fat go? BMJ, 349(dec16 13), g7257–g7257. https://doi.org/10.1136/bmj.g7257 >Our calculations show that the lungs are the primary excretory organ for fat.
The survey in that study always left me with some complicated feelings. How is it possible that 100% of family doctors get this wrong, and what does this mean for their core competencies? Don't get me wrong, I'm humble enough to understand they know infinitely more than I do, and I respect that their education and experience makes them completely capable of doing their job. But then how can they miss such a trivial u…
> completely capable of doing their job [...] But then how can they miss such a trivial understanding [...] It just doesn't match up.
People badly underestimate how very rapidly understanding degrades as you move away from someone's focus of expertise.
You might laugh if you heard a conversation "You're a Doctor? Yes, of medieval french literature. Good, what do you think of my blood pressure medication?". Or people looking to their local TV meteorologist for climate-change-isn't-real expertise. Or "he's a Scientist!".
The press gets excited when say first-tier business school students don't know what causes Earth's seasons. But if the last time they touched a topic was middle school, it shouldn't shock to find a middle-school-ish understanding. Asking a protein chemist a quantum chemistry question is perhaps like asking a years-ago "I hate studying for quals" graduate student. If something isn't a focus, there's little selection pressure to prune misconceptions.
But perhaps one expects a 5-year old asking "What color is that Sun ball thing?" of first-tier astronomy graduate students to go well? Doesn't. And many of the few who get it right, learned it discussing common misconceptions in astronomy education, rather than from their own.
As you move away from people's active focus, understanding can become ramshackle startlingly fast.
Re: When we lose weight, where does it go?
#98For the science geeks, here's a great TEDx demonstration with lab experiments: "The mathematics of weight loss " https://www.youtube.com/watch?v=vuIlsN32WaE
The presenter in the video is one of the authors of the article.
Re: When we lose weight, where does it go?
#99Water and CO2? (And, of course, some other byproducts, but by and large.) I mean, I think this is a well-known answer, no? Sorry I don't mean to sound facetious, I haven't opened the article, so I may be surprised, but I thought this was standard knowledge (at least, it was taught in middle school and high school, even though that's been a while ago for me).
It's actually like 85% to 90% CO2 by weight IIRC, can't remember the chemistry off the top of my head, but I remember being shocked by that.
You literally breathe most of the weight off.
Edit: Found a source, memory was about right. Per this info-graphic [0] and this paper [1], approximately 84% of fat loss by mass is exhaled as CO2.
[0]https://www.bmj.com/content/bmj/349/bmj.g7257/F2.large.jpg [1]https://www.bmj.com/content/bmj/349/bmj.g7257.full.pdf
Re: When we lose weight, where does it go?
#100Earlier quoted context omitted.
Not that well known in some circles. I decided this year to lose some weight and only worked out the mechanics of it after researching throughly. It never factored into my education or general knowledge. It was demotivating to be honest knowing how much of me I had to breathe out. I will say that it was one of the best changes I ever made to my life.
> I will say that it was one of the best changes I ever made to my life. Wohoo! That's awesome, congrats! :) It is rather surprising just how much air needs to be exchanged, which is crazy and definitely not intuitive. (And I could definitely see how it could be demotivating... but, hey, we do breathe out quite a bit!)
Wow interesting. So I feel like I don’t breathe correctly. Could it be the reason why I can’t lose weight :D?