samtalksfunny:

Expanding on my last post about supersoldier metabolism… bear in mind I’m not a doctor or a nutritionist, just an enthusiastic and curious amateur, so I welcome input or corrections.

So.  Couple of questions.  Enough about the raw calories required for supersoldiering… What about alcohol? What about painkillers? It’s NOT the case, I don’t think, that ‘supersoldier metabolism is just too fast for them.’  I think there’s a lot more going on.

1. We need to consider that individual response to alcohol is ALREADY variable: different people can metabolize alcohol more or less well. Much of our ability to metabolize alcohol usefully is genetic. So genetic modification could easily fix any problems that occur due to the byproducts of oxidizing alcohol.

2. Second option is that supersoldiers’ enhanced healing ability comes in and ‘cleans up’ the tissue damage caused by these byproducts.  Presumably that’s just the result of enhanced immune function.

OK.  Now what about the common canonical issue with supersoldiers and how their ‘metabolism’ gets rid of drugs or reduces the effect.

1. Let’s consider opioids.  These work similarly to the body’s own painkillers.  Easy reason this might not work well with supersoldiers?  Frankly, it’s very likely that their bodies undergo such chronic acute trauma that they actually develop a tolerance to their own endogenous opioids.  Thus, exogenous painkillers wouldn’t work except in massive doses–and it would be a vicious cycle, as, presumably, supersoldiers ALSO adapt more quickly to increased dosage and would become tolerant to THAT, too. I like this theory because it explains how they aren’t necessarily sustaining less damage or feeling less pain than a normal person would; they’re simply healing faster.  Therefore, it makes sense that their internal painkilling drugs wold have to work overtime and that they would develop a tolerance to their own pain-suppressing neurochemicals.  

2. Aspirin or other anti-inflammatories: seems pretty straightforward. The endogenous anti-inflammatory response is too fast to need ‘help’ from aspirin or ibuprofen.  MAYBE they have enhanced ability to convert omega-6 fatty acids to omega-3 to take advantage of eicosanoids/other stuff that fights inflammation, etc.  Or maybe SHIELD nutritionists/HYDRA nutritionists(??? dude HYDRA NUTRITIONISTS I want that job) give Captain America/The Winter Soldier a lot of fish oil.  Well hey, the Russians eat a lot of smoked fish!

oh my god now I want to write a fanfic where a HYDRA nutritionist recommends they feed the Winter Soldier more herring that would be amazing.

ETA: oh my god it would be RED herring if the Russians gave it to him.

ETA 2: this sounds like a Hydra Trash Party fic (”Brock Rumlow feeds the asset a herring”) except it would just be literally a freaking herring.

P.S. I have way, way more thoughts on all of this but it’s getting a little technical…

samtalksfunny:

I’ve been reading a lot of fics that handwave the ‘supersoldier metabolism’ (Captain America, Winter Soldier).  Some thoughts.

1. There is startlingly little variance in actual metabolism, aka BMR, among  normal human beings (steroid users are KIND OF outliers, but primarily all that changes is that more surplus calories go to muscle tissue, not fat–so, sort of like supersoldiers). What variance in BMR there is may be attributed to lean tissue increase (aka, more muscles more burn) and increased activity even if it’s unconscious (NEAT). 

2. The astounding amounts of food some athletes eat are attributable primarily to their ability to tolerate huge workloads. I.e. if Michael Phelps weren’t so fast a swimmer and thus able to swim so far and so hard in a single session, he wouldn’t burn calories like he does when training.  (And, indeed, when he isn’t training, he doesn’t have to eat that much).  So it’s not like if Captain America lay around doing nothing he’d still need that much food.  But when he’s running a half-marathon in 30 minutes, he’d be burning just as many calories as if a normal 240-pound man ran a half marathon in an hour and 30 minutes. [By the way, that’s me being very generous… I’ve never met a 240-lb man who can run a half marathon in 1:30.  I weighed about half that much when I did it myself, that’s a sub-7:00-mile pace.]  So that would mean he’s burning roughly 2400 calories… in THIRTY MINUTES.  Think about that.  It’s not that his resting metabolism even needs to be so high–it’s that he’s able to do this superhuman feat and that requires tremendous energy.

3. I think probably supersoldiers are just super-fit. Their mitochondria are able to synthesize ATP at an unprecedented rate.  NOW, seeing THAT, you might think: okay, so they require a lot of carbohydrate, but what happens if they didn’t pack a Power Bar? (First of all, they very likely do keep extra fuel on hand).  Also–why don’t they waste away if deprived of food? 

4. Well, because they’re probably metabolically FLEXIBLE.  I imagine they are able to use ketones for fuel more efficiently than normal people, for one thing–i.e. can use fat for fuel more efficiently than normal humans, vs. relying on carbohydrate; some ultra-endurance athletes train themselves to do this.  There has been some interesting, though potentially sketchy, research on exogenous ketones as a performance enhancer, too. I guess with supersoldiers they might be endogenous!  (exogenous–supplied from outside; endogenous–produced in the body)  Some of this research was about enhancing Navy SEALs’ ability to perform in depth dives. Hey, maybe that’s how the Winter Soldier rescued Cap.

5. I also imagine supersoldiers may be able to metabolically downregulate more quickly than normal humans do–i.e. their BMR can radically adjust itself.  And finally, they can store more glycogen than normal people.  But really, burning fat more efficiently would be the most likely explanation, since so many thousands of calories of fat are available on even relatively lean people (and note that I don’t think the superheroes are sub-7% bodyfat! Note that actual soldiers are not meant to attain very low body fat, as it’s a liability in the field).  

6. By the way, metabolic flexibility/the idea of superheroes being able to attain some sort of hibernation state… kind of explains why Cap survived being frozen and why the Winter Soldier was able to hold up during cryo so well.

7. As a side note, the reason Alexander Peirce probably offered the Winter Soldier milk is that intracellular calcium is super-important for muscle contraction.  I bet SHIELD nutritionists make sure Steve gets plenty of calcium, potassium, and magnesium–though with caloric requirements in the quintuple digits it’s difficult to get a shortfall of anything.