The FDA has warned old people to stop infusing plasma from young people in order to slow down the aging process, saying it has "no proven clinical benefit" according to Bloomberg.

In a Tuesday safety alert, the agency suggested that old people getting scammed with $8,000 per liter plasma to treat age-related issues including dementia, Parkinson's disease, Alzheimer's disease and heart disease.

"There is no proven clinical benefit of infusion of plasma from young donors to cure, mitigate, treat or prevent these conditions, and there are risks associated with the use of any plasma product," reads a statement from FDA Commissioner Scott Gottlieb and Peter Marks, who leads the agency's biologics center.

The idea of infusing young blood to fight aging has attracted technology entrepreneurs like billionaire Peter Thiel and was lampooned in a 2017 episode of the HBO show “Silicon Valley.” Thiel’s reported interest was sparked by a company called Ambrosia, which has locations in five states across the U.S. and sells one liter of blood plasma from donors between the ages of 16 and 25 for $8,000, according to its website. Gottlieb and Marks said none of the plasma treatments has gone through the rigorous testing required by the agency. Ambrosia says “experiments in mice called parabiosis provided the inspiration to deliver treatments with young plasma.” The FDA approval typically requires human trials before companies can make a specific health claim about a product.

"The reported uses of these products should not be assumed to be safe or effective," said Gottlieb and Marks. "We strongly discourage consumers from pursuing this therapy outside of clinical trials under appropriate institutional review board and regulatory oversight."

Plasma infusions are an FDA approved treatment intrauma settings or for people whose blood doesn't coagulate, however the agency notes there are risks, including circulatory overload, allergic reactions, lung injury and the transmission of infectious diseases.

"We’re concerned that some patients are being preyed upon by unscrupulous actors touting treatments of plasma from young donors as cures and remedies," say Gottlieb and Marks. "Such treatments have no proven clinical benefits for the uses for which these clinics are advertising them, and are potentially harmful."

As we noted in January, Ambrosia was launched by Stanford University graduate Jesse Karmazin, who charges $8,000 for one liter of young blood, and $12,000 for two liters. Karmazin, who isn’t a licensed medical practitioner, told reporters last year that he had hoped to open his first clinic in New York City by the end of 2018 - however following Tuesday's FDA announcement, they are no longer treating patients according to their website.

As of last fall, the company had performed the procedure on about 150 people ranging in age from 35 to 92, while 81% of those people participated in the company's clinical trial. The trial gave patients one and a half liters of plasma from a donor between the ages of 16 and 25 and was conducted with David Wright, a physician who has his own intravenous blood therapy center in California.

Trial participants footed the bill for their own treatments - while the results of their clinical trials have not been publicly released.

"The trial was an investigational study. We saw some interesting things, and we do plan to publish that data. And we want to begin to open clinics where the treatment will be made available," the company's COO said... several months before he left.

And now, it appears that those wanting to procure young blood will need to hunt elsewhere.