Let’s say you are dying of starvation. You pull one of your teeth out, causing blood to slowly seep into your mouth, which you swallow. The calories from the blood getting digested will delay the time you die of starvation, right? Or will losing blood while starving kill you faster?
If you have calories in your blood, you should leave them in there to get used instead of taking them out and back in. You wouldn’t be adding usable energy, you already had it.
You have energy stored in fat and muscle, but your body already is going to try and consume those without all that added stress of eating yourself from the outside.
You can never, ever get a net gain from self cannibalism of any kind. Digesting takes energy, and you’re also having to heal/replace whatever it is you’re eating.
Besides, the amount of blood that will come from a pulled tooth isn’t enough to do anything useful. You wouldn’t even gain minutes from it if the source was external.
That would be akin to running a hose out of your car’s gas tank and back in. You’d use some gas for the pumping and add none back in the process.
Something to consider is that your body relies on blood glucose as its primary energy source. During starvation, glucose levels are severely depleted. This triggers your body to start using stored fatty acids. All remaining glucose is reserved for the brain to use.
By removing blood from your body and moving it to your stomach, you’re essentially moving that precious energy to an organ that can’t as readily make it available to the tissues that need it.
Thanks to the thermic effect, it also takes energy to digest and metabolize food. You’d be expending extra energy to digest the blood that was already in your body, where it was perfectly content carrying usable energy where it was needed.
