And finally… suckers

Ambrosia, a start-up based in San Francisco, has already injected two and a half litres of plasma into more than 100 patients / customers with an average age of 60.

Founder Jesse Karmazin, 32, claims: “It could help improve things such as appearance or diabetes or heart function or memory. These are all the aspects of ageing that have a common cause. I’m not really in the camp of saying this will provide immortality but I think it comes pretty close, essentially.”

He added: “We’re already seeing people look better after just one treatment. It’s like plastic surgery from the inside out.”

The firm buys surplus blood from blood banks, from teenage donors where possible.

The two and a half litres of plasma is a mix of blood from several donors.