Fed up with your kids bleeding you dry or just in need of some young blood?
Ambrosia is a startup charging customers US$8,000 for a transfusion of blood from a donor under 25.
Now it's conducting what it describes as a clinical trial on some of the 100 recipients of these transfusions to measure the health effects.
At this stage, the only good evidence comes from animal studies on mice, where an older mouse is surgically connected to a younger mouse, and they share blood.
This gory-sounding procedure is called parabiosis and the result seems to be that the young mice get sick and the older mice feel great.
But critics claim it's shonky science, pointing to the problems of running a human study where the participants are effectively paying to participate, and there's no control group to measure the placebo effect.
We speak to Ambrosia's founder Jesse Karmazin about the approach, and to Professor Matt Kaeberlein who studies ageing at the University of Washington about the value of the proposed study.