2y ago

How many calories does a standard whole blood donation burn?

So I just went and donated blood again and durring the recovery period it occured to me that it takes quite a bit of work for your body to regenerate that lost blood volume and the actual blood cells. Regrowing that many cells seems like it would be fairly energetically intensive. So how many calories does producing all those new blood cells actually consume? Is there even a way to know that?

22 comments

Oh man, instead of my daily workout, I could just donate daily! After a few months, I’d be a blood making machine!
- But once your body gets used to pumping out so much extra blood, if you skip donate day you will plump up and explode
  
  Nah man, I’ll look vascular and jacked!!
- If you're however old you are now and still not a blood making machine, I'd say see a doctor.
  
  As a chronically anemic person, I need other people's blood making machines.
  Go donate if you can! I will take your sweet, sweet red blood cells.
The number floating around the web is 650 calories but I haven't been able to track down the actual source.
(Google Scholar is no help at all. Whoever these UCSD researchers are, I have no bloody clue.)
- So I can shotgun two pints of beer after a donation (gotta rehydrate!) and still be a couple hundred calories ahead? Win-win!
  
  And you'll get drunker due to the blood loss!
  
  Jokes aside, you shouldn't drink alcohol the day before and after your donation
- Hmm. Not as much as I hoped. You could probably eat that many calories in the free snacks they have afterwords without anyone even looking at you funny.
  
  Eat the snacks before donating. That way your blood glucose spikes and you 'burn' maximum calories.
It’s something you’ll never truly figure out and can’t really as your body is a constant state of maintenance. When my brother was rushed to the hospital with pneumonia, the next day he didn’t really grow a beard. Makes sense. When you’re at deaths door, maybe don’t worry about growing hair.
Your body is always managing resources.
Basically it’s going to take the energy needed from other maintenance items (hair, nails, skin, etc.) and devote them to blood manufacturing. It’s also going to cut your energy to save calories so you’ll feel pretty sluggish for a bit.
How we currently deal with calories is just wildly misleading.
- Yeah. "Calories in calories out" is correct in theory but it is an oversimplification. Most people burn a vastly majority of their calories "at rest" by just maintaining their body temperature.
I've always been under the belief it's a day's worth of calories.
I dunno. I usually give platelets.

22 comments