That's a good question. It depends on many factors like age and frequency, which might be why it's so popular with college students! Donations clear the blood

That's a good question. It depends on many factors like age and frequency, which might be why it's so popular with college students! Donations clear the blood of stuff like cholesterol and microplastics, so the first donation can leave one feeling better the next day. Donating twice a week can be more taxing on the body and result in stuff like a lower body temperature, slower heartbeat and lower blood pressure because the heart doesn't have to work so hard to pump thinner blood. I'm mostly concerned about using up the body's regenerative ability, since nobody knows how many times that plasma can be synthesized over a lifetime. But many of the components in blood have a natural recycling rate anyway. I suspect that the body can't tell if it's building new plasma from old plasma or nutrients in food though. Without more evidence, I feel that it's better to rely on the expertise of the medical community than speculation. Just my two cents, YMMV.