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>They drink blood because their own blood accumulates factors that accelerate aging, and they need to periodically dilute it. Feeding isn’t nutrition. It’s dialysis.

This seems to be the emerging consensus. When you get older your metabolism creates all kinds of crap that circulates in the blood.

You would like to have boosted kidneys parallel to real ones that can detect and remove all the slightly wrong proteins.

2 comments

To reframe the argument, it's more likely that mechanisms for clearing cellular debris become less effective with age.

Are there any reasons for this to work on non-vampires? :D

That was my thought as well. At least naively, it seems to follow that regularly donating blood might have health benefits. A typical donation is half a liter, and a person has about 5 liters of blood, so donating should in theory remove about 10% of the crap you've got circulating, right?

Edit: You can donate every 2 months, so donating as often as possible would roughly halve the crud every year (0.9^6 ~= 0.53, ignoring the natural increase over time).

I don't think it's very effective.

It's your metabolism that produces that junk with increasing ratio of stuff that you need. If you just remove blood, the ratio of good stuff to bad stuff does not change. Same with kidney filtering if they can't recognize the difference.

Blood transfusion from younger person gives you blood with better ratio.

The article includes a citation that explicitly states the opposite. Specifically citation 20 from the section "The Twist" (which is itself all about this idea):

> [20] Mehdipour, M. et al. “Rejuvenation of three germ layers tissues by exchanging old blood plasma with saline-albumin.” Aging 12(10), 8790–8819, 2020. The UC Berkeley team found that diluting old blood plasma with saline and albumin produced rejuvenating effects comparable to young blood — suggesting the mechanism is removing pro-aging factors rather than adding youth factors. This was, at the time of publication, the strongest evidence that old blood is the problem, not that young blood is the solution.

Maybe regularly donating blood would have more negative effects from losing good stuff than positive effects from losing bad stuff, or maybe not. There is evidence that it could be a net positive though.

And even aside from the buildup of crud due to normal aging, environmental crud (nano/microplastics, PFAS, etc) is not produced by the body. It's still not totally settled science whether all of those things have negative effects, but regular blood donation would help clear it out, at least a little.

I was waiting for someone to consider the idea of synthetic dilutants.

But a further horror is: you’re dumping your crud on the person getting your transfusion? I guess it’s better than dying in ER.

Yeah, unless your blood is significantly more cruddy than average, the recipient shouldn't really care that you had ulterior motives behind donating.

The article confirms what I just wrote. Albumins are proteins. If you add more albumins, the ratio changes.

dilution = change of ratio. Just giving blood is not dilution.

> it seems to follow that regularly donating blood might have health benefits

It's pretty effective if you have excess iron (hemochromatosis) and your local vampires accept your donation; some don't because a donation where you get a significant benefit isn't a donation for the sole reason of helping others (and a free cookie). In that case, traditional bloodletting may be required.

In New Zealand, you are stopped at 75 (or 81 if given an exemption) assuming you started donating before 71.

You can't start donating blood after 71.

From age section: https://www.nzblood.co.nz/become-a-donor/am-i-eligible/detai...

Yeah, that is donating, now I wonder donating AND receiving (from a healthy individual). :D

Why do you think Gavin Belson had a blood bag? This has been a trope for a while. They even had blood bags in the Fury Road movie, but that was more of a continuous supply than just trying to refresh like Gavin. I don't think using movie tropes in a discussion on vampires is out of line here

2 months for whole blood IIRC. You can do every 2 weeks for platelets, but I am not sure if that removes the crud or not. There's other donations with varying frequency (red, plasma, etc.).

I'm assuming this is in the US? I'm curious why it's 2 months there but 3 or 4 (men/women) in the UK.

I don't donate whole blood too often (they usually want me for platelets every 2 weeks if they can get it).

https://versiti.org/ways-to-give/about-blood-donation/blood-...

56 days or 8 weeks for whole blood.

It doesn't say why.

More vampires further north, so most people have less extra blood?

But more seriously, it seems like 2 months is enough for most people, but not everyone. So it just comes down to whether you want to turn some people away at donation time because their iron is too low, or make everyone wait a bit longer between regular donations.