One US based start-up wants to give older people young blood transfusions.
San Francisco based 'Ambrosia' will run a controversial trial showcasing the 'advantage' of young blood transfusions.
They claim: "Regular transfusions of the blood of a younger, physically fit donor can significantly retard the aging process."
Anyone over the age of 35 can enroll as a recipient, provided they can afford $8,000 per transfusion.
The blood will come directly from banks and only the plasma is transferred to the recipient.
The trial and method is based on a 2014 Stanford study in which old mice were given the blood of young mice - they reportedly then behaved as if they were younger.
The trial's 600 subjects are age 60 and average but scientists are already sceptical of the study.