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Bryan Johnson has taken his reverse aging journey to new levels, conducting “the world’s first multigenerational plasma exchange” with his then 17-year-old son and 70-year-old father earlier this year. His hefty team of 30-plus doctors approved the protocol as a way to potentially influence age-related brain decline.
But now, Johnson has concluded there were “no benefits” after religiously checking a range of biomarkers from his fluid. In a tweet he shared earlier this week, Johnson said he underwent six, 1-liter “young plasma exchanges”—and that one was his son’s plasma.
“Young plasma exchange may be beneficial for biologically older populations or certain conditions,” Johnson's tweet reads. “Does not in my case stack benefit on top of my existing interventions. Alternative methods of plasma exchange or young plasma fractions hold promise.”
The procedure removes a liter of blood from a young donor, which is then extracted into red blood cells, white blood cells, platelets, and plasma (roughly 55% of our blood is plasma, according to the Red Cross). The converted plasma is then injected into the recipient with the goal of regenerating parts of the body in the name of anti-aging. Johnson and his son both gave their blood; Johnson had his son’s plasma injected into his veins while his own plasma was injected into his father’s veins for an intergenerational trifecta experiment, according to Bloomberg.
Johnson's father's results are “still pending,” he added in the tweet.
Since Bloomberg profiled him in January, Johnson has become known for his extravagance and discipline by spending millions of dollars on anti-aging remedies, publicly documenting his anti-aging regime under the name “Project Blueprint.” It consists of a strict diet, exercise, sleep routine, and consistent organ and blood tests to determine if he is becoming biologically younger. Plasma transfusion is just one of the many procedures he has undergone in the name of longevity, although it's deemed controversial. (Johnson’s team did not reply to a request for comment.)
The young blood controversy
Ambrosia, a start-up in California, sold young plasma transfusions for $8,000 per liter beginning in 2017. However, it shut down in 2019 when the Federal Food and Drug Administration (FDA) warned against these types of plasma transfers, Business Insider reported.
“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,” the FDA’s 2019 statement reads, referring to age-related diseases like heart disease and Alzheimer's.
The statement continues: “Treatments using plasma from young donors have not gone through the rigorous testing that the FDA normally requires in order to confirm the therapeutic benefit of a product and to ensure its safety. As a result, the reported uses of these products should not be assumed to be safe or effective.”
Plasma transfers have been used for severe infections, burns, and blood disorders, but evidence has not concluded their use for anti-aging purposes.
“We have not learned enough to suggest this is a viable human treatment for anything,” Charles Brenner, a biochemist at City of Hope National Medical Center in Los Angeles, told Bloomberg. “To me, it’s gross, evidence-free, and relatively dangerous.”
According to a study published in the American Chemical Society publications in 2019, researchers examined how young blood transfusions affected the cognitive function of mice. The results suggested older mice experienced signs of regeneration in their brains, muscles, and some tissues. Still, these associations have not been proven in humans.
“Research to slow or halt aging is more complex than searching for regenerative factors in blood,” Irina M. Conboy from the University of California, Berkeley, said in the study.
And after the FDA cautioned against young plasma transfers, research has instead turned its attention elsewhere.
“In the wake of the initial fervor surrounding young blood, researchers are taking a more measured approach. Rather than trying to reverse aging, they’re identifying the molecular factors responsible for the changes seen in parabiosis experiments in hopes of targeting specific diseases associated with aging, such as age-related macular degeneration or Alzheimer’s disease,” the 2019 research paper reads.
While Johnson is throwing darts at the longevity board and seeing what sticks, young plasma transfusions don't seem to make the cut. He announced on Twitter that the therapy has been discontinued.