5 ms·

Why you lose a pound of weight at night in your sleep

pdog 13y ago
Is this actually true, or is it water vapor (H2O) that we're expelling each night?
usea 13y ago
Just because you're inhaling molecules that have 2 oxygen atoms, and exhaling molecules that have 2 oxygen atoms for every 1 carbon atom, doesn't mean you're exhaling more matter than you're inhaling. The numbers are ratios. They don't imply a larger volume. Not to mention the composition of what you inhale and exhale is not simply oxygen and carbon dioxide. As it usually goes, reality is much more nuanced than this short article implies. I know nothing about this topic. I definitely don't know enough to say this reason for losing weight is wrong. However, the explanation is utterly unconvincing. edit: apparently there's a youtube video that didn't load for me the first time. I think it's trying to say that for the same volume CO₂, there's more mass? I think I should have avoided commenting on a subject that I know little about.
gus_massa 13y ago
See the video! It's has interesting information in spite of the informal format. Back of the envelope calculations at 5:15 (I checked them and look legit) Experimental measures at 2:06 and 4:07.
- gus_massa 13y ago
  But it's also possible to gain some mass from the Oxygen in the air. The burning reactions for example typical compounds are: Typical sugar (Glucose) C6H12O6 C6H12O6 + 6 x O2 (air) ---> 6 x CO2 (air) + 6 x H2O 6 Carbons get exhaled, and you lost a little of mass. Typical Fatty Acid (Palmitic) CH3(CH2)14COOH CH3-(CH2)14-COOH + 23 x O2 (air) ---> 16 x CO2 (air) + 16 x H2O 16 Carbons get exhaled, but 14 Oxygens get absorbed in water. The mass of the Oxigens (14x16) is slightly more than the mass of the Carbons (16x12), so you gain a little of mass. But this is much smaller. Typical aminoacid: more complicated. I think that the total mass lost dew to the first kind of reaction is much bigger than the total mass gained dew to the second. So the calculations in the video are probably a good approximation. (Anyway, most of the difference is water (transpiration / exhaling).)

pdog 13y ago

Is this actually true, or is it water vapor (H2O) that we're expelling each night?

usea 13y ago

Just because you're inhaling molecules that have 2 oxygen atoms, and exhaling molecules that have 2 oxygen atoms for every 1 carbon atom, doesn't mean you're exhaling more matter than you're inhaling. The numbers are ratios. They don't imply a larger volume. Not to mention the composition of what you inhale and exhale is not simply oxygen and carbon dioxide. As it usually goes, reality is much more nuanced than this short article implies. I know nothing about this topic. I definitely don't know enough to say this reason for losing weight is wrong. However, the explanation is utterly unconvincing. edit: apparently there's a youtube video that didn't load for me the first time. I think it's trying to say that for the same volume CO₂, there's more mass? I think I should have avoided commenting on a subject that I know little about.

gus_massa 13y ago

See the video! It's has interesting information in spite of the informal format. Back of the envelope calculations at 5:15 (I checked them and look legit) Experimental measures at 2:06 and 4:07.

gus_massa 13y ago
But it's also possible to gain some mass from the Oxygen in the air. The burning reactions for example typical compounds are: Typical sugar (Glucose) C6H12O6 C6H12O6 + 6 x O2 (air) ---> 6 x CO2 (air) + 6 x H2O 6 Carbons get exhaled, and you lost a little of mass. Typical Fatty Acid (Palmitic) CH3(CH2)14COOH CH3-(CH2)14-COOH + 23 x O2 (air) ---> 16 x CO2 (air) + 16 x H2O 16 Carbons get exhaled, but 14 Oxygens get absorbed in water. The mass of the Oxigens (14x16) is slightly more than the mass of the Carbons (16x12), so you gain a little of mass. But this is much smaller. Typical aminoacid: more complicated. I think that the total mass lost dew to the first kind of reaction is much bigger than the total mass gained dew to the second. So the calculations in the video are probably a good approximation. (Anyway, most of the difference is water (transpiration / exhaling).)