What is young blood / plasma exchange, and does it actually work?
Plasma exchange clearly works in mice, but in humans there is still no evidence whatsoever of efficacy or safety. Do not be tempted by commercial providers offering young plasma as a rejuvenation treatment.
Young blood or plasma exchange is based on a simple idea: if you surgically connect the circulatory systems of a young and an old animal, the old tissues recover more effectively. This has been studied extensively in mice. In those experiments, tissue repair and stem cell function in old mice improved in a clearly visible way. The most plausible explanation is that young blood contains substances that slow ageing, while old blood contains substances that promote it.
What blood does to the brain and blood vessels is telling. Mouse studies show that administering young plasma produces partial cognitive recovery and improves brain plasticity in the memory region. Blood also influences how permeable the blood-brain barrier is and how many small blood vessels are present in the brain. The effects are measurable, but they always involve mice, not humans.
A related idea is the use of tiny vesicles released by stem cells. Animal research shows that these vesicles can restore blood vessel formation in old mice to levels comparable to those of young animals, and that markers of cellular ageing in organs decrease. This too has so far been demonstrated exclusively in mice.
Whether this works in humans is the big open question. The researchers themselves acknowledge that there are serious hurdles: safety has not been established, practical implementation is complex, and it is uncertain whether the effects seen in mice will also occur in humans. Early clinical studies are under way, but results in humans have not yet been published based on the available studies. The US regulator has already issued warnings about commercial plasma transfusions marketed as rejuvenation, with companies offering young plasma without any proven benefit in humans.
All claims are based on reviews; the animal research (mice, parabiosis) is the most fully developed. No published human RCT results are available in the sources provided. One source (PMID 37367945) has not been further indexed by PubMed.
Is donating blood regularly good for your health?
Regular blood donation is safe for many people, but it can deplete your iron stores, especially if you menstruate or donate frequently. Have your ferritin level checked regularly and discuss your donation frequency with your doctor if you want to become pregnant or are feeling tired.
Does red light therapy really have an effect on your cells?
Red light therapy has a biologically plausible effect on cells, with positive clinical indications for pain and recovery, but standard doses are lacking and home devices have not been sufficiently studied. Interest is justified, but keep your expectations realistic until more standardised research is available.
Can fasting really rejuvenate your cells?
Fasting has clear cell-rejuvenating effects in animal research, but in humans the evidence is still limited to small studies using biomarkers. The most promising findings have not yet been confirmed in large human studies, so caution is warranted.
Does quercetin work against ageing and inflammation?
Quercetin shows promising signals in the laboratory and in animals, but in humans there is not yet solid evidence. Taking supplements on the basis of this early-stage research gets too far ahead of the science.
Does hyperbaric oxygen therapy help against ageing?
HBOT shows interesting signals in small, early studies regarding telomere length and cerebral blood flow, but the evidence is too thin and too susceptible to bias to recommend it as an anti-ageing treatment. Wait for larger, independent trials before taking on the considerable costs.
What do we really know about metformin and ageing?
Metformin may extend your healthy years by helping to prevent disease, from diabetes to heart and vascular disease. Whether it also slows ageing itself in people without diabetes is for the TAME trial to show, the first large study to test that directly. If you are considering it for that reason, expect stomach and bowel complaints and a falling folate level.