Skip to Content
Biotechnology and health

Why the sci-fi dream of cryonics never died

The idea that humans could be frozen and later brought back has survived for decades. The hope is still alive and even growing today—never mind that it’s still not possible.

October 14, 2022
An open door in a corrugated metal building
The entrance to the Moscow storage facility of KrioRus, which was until recently the only cryonics company in Eurasia.Alessandro Gandolfi

When Aaron Drake flew from Arizona to the Yinfeng Biological Group in China’s eastern Jinan province in 2016, he was whisked into a state-of-the-art biotech hub. More than 1,000 staffers—including an army of PhDs and MDs—were working on things like studies of the stem cells in umbilical cord blood. The center specialized in research on human cells, from gene testing to tailored cancer treatments. 

But it also had other plans: cylindrical stainless-steel tanks would eventually contain corpses suspended in liquid nitrogen. The tanks weren’t installed yet, but Yinfeng hoped Drake would help with that while it invested some $7 million to get the new project off the ground. As its high-profile new hire, he was there to guide China’s first forays into cryonics, or freezing corpses for reanimation.

The environment was something of a shift for Drake, who had spent the previous seven years as the medical response director of the Alcor Life Extension Foundation. Though it was the longtime leader in cryonics, Alcor was still a small nonprofit. It had been freezing the bodies and brains of its members, with the idea of one day bringing them back to life, since 1976. 

The foundation, and cryonics in general, had long survived outside of mainstream acceptance. Typically shunned by the scientific community, cryonics is best known for its appearance in sci-fi films like 2001: A Space Odyssey. But its adherents have held on to a dream that at some point in the future, advances in medicine will allow for resuscitation and additional years on Earth. Over decades, small, tantalizing developments in related technology, as well as high-­profile frozen test subjects like Ted Williams, have kept the hope alive. Today, nearly 200 dead patients are frozen in Alcor’s cryogenic chambers at temperatures of −196 °C, including a handful of celebrities, who have paid tens of thousands of dollars for the goal of “possible revival” and ultimately “reintegration into society.”

But it’s the recent involvement of Yinfeng that signals something of a new era for cryonics. With impressive financial resources, government support, and scientific staff, it’s one of a handful of new labs focused on expanding the consumer appeal of cryonics and trying anew to bring credibility to the long-disputed theory of human reanimation. Just a year after Drake came on board as research director of the Shandong Yinfeng Life Science Research Institute, the subsidiary of the Yinfeng Biological Group overseeing the cryonics program, the institute performed its first cryopreservation. Its storage vats now hold about a dozen clients who are paying upwards of $200,000 to preserve the whole body. 

Still, the field remains rooted in faith rather than any real evidence that it works. “It’s a hopeless aspiration that reveals an appalling ignorance of biology,” says Clive Coen, a neuroscientist and professor at King’s College London.

Even if one day you could perfectly thaw a frozen human body, you would still just have a warm dead body on your hands.

The cryonics process typically goes something like this: Upon a person’s death, a response team begins the process of cooling the corpse to a low temperature and performs cardiopulmonary support to sustain blood flow to the brain and organs. Then the body is moved to a cryonics facility, where an organ preservation solution is pumped through the veins before the body is submerged in liquid nitrogen. This process should commence within one hour of death—the longer the wait, the greater the damage to the body’s cells. Then, once the frozen cadaver is ensconced in the cryogenic chamber, the hope of the dead begins. 

Since its beginnings in the late 1960s, the field has attracted opprobrium from the scientific community, particularly its more respectable cousin cryobiology—the study of how freezing and low temperatures affect living organisms and biological materials. The Society for Cryobiology even banned its members from involvement in cryonics in the 1980s, with a former society president lambasting the field as closer to “fraud than either faith or science.” 

In recent years, though, it has grabbed the attention of the libertarian techno-­optimist crowd, mostly tech moguls dreaming of their own immortality. And a number of new startups are expanding the playing field. Tomorrow Biostasis in Berlin became the first cryonics company in Western Europe in 2019, for example, and in early 2022, Southern Cryonics opened a facility in Australia. 

“More researchers are open to longer-­term, futuristic topics than there might have been 20 years ago or so,” says Tomorrow Biostasis founder Emil Kendziorra. 

The Society for Cryobiology has even dropped its past cryonics-related restrictions. And now its president, cryobiologist and biogerontologist Greg Fahy, is behind a company called 21st Century Medicine, which develops techniques to cryogenically preserve human organs and tissues. (Still, the society said in a statement to MIT Technology Review that cryonics “is an act of speculation or hope, not science.”)

Today, around 500 people are preserved in liquid nitrogen globally, the vast majority in the United States. Around 4,000 people are on waiting lists of cryonics facilities around the world, says Kendziorra. Alcor has around 1,500 members, and Tomorrow Biostasis already has 300 clients paying a relatively accessible monthly membership fee of €25 (with €200,000 payable at the time of death).

Despite a lack of evidence that dead people could one day be brought back to life, cryonicists perhaps unsurprisingly remain optimistic, noting that tissues like sperm, embryo, and stem cells can be successfully cryopreserved and thawed right now, and that researchers claim to have cryogenically frozen and thawed small worms and rabbit kidneys. Researchers at 21st Century Medicine, for instance, cryopreserved and thawed a rabbit brain in 2016 and a pig brain in 2018. 

But Dayong Gaom, a cryobiologist and professor at the University of Washington, points out preserving the brain’s structure does not mean preserving its functions. KCL’s Coen says it’s “disingenuous” to say these studies support the aims of cryonics and maintains that brain structures are far too complex to be adequately preserved and revived in the way cryonicists claim.  

There’s also been some progress, though, in finding a way to rewarm frozen tissues. A research group at the University of Minnesota showed that nanowarming techniques, using radio-frequency-excited nanoparticles of iron oxide, could work on larger samples of 50 millimeters. The team has now successfully thawed whole rat organs in a way that preserves cell structure and is nontoxic to cells, with a view to restoring the organ’s functions. It is now experimenting with pig organs.

Yinfeng is devoted to solving the same problem—it’s currently experimenting with cryogenic methods to preserve individual human organs and amputated extremities to boost China’s national transplant program. 

But none of these developments lead to a possible way to eventually revive a living person. Even if one day you could perfectly thaw a frozen human body, you would still just have a warm dead body on your hands. The hardest part to reverse—death itself—remains an enigma.

This is not lost on Drake. But the clients seeking cryonics services are often “either agnostic or atheist,” he says. “Instead of a faith in a supreme being, they have faith in science—that science, more specifically medical science, will eventually figure this out.”

Laurie Clarke is a technology journalist based in the UK.

Deep Dive

Biotechnology and health

How scientists traced a mysterious covid case back to six toilets

When wastewater surveillance turns into a hunt for a single infected individual, the ethics get tricky.

An AI-driven “factory of drugs” claims to have hit a big milestone

Insilico is part of a wave of companies betting on AI as the "next amazing revolution" in biology

The quest to legitimize longevity medicine

Longevity clinics offer a mix of services that largely cater to the wealthy. Now there’s a push to establish their work as a credible medical field.

There is a new most expensive drug in the world. Price tag: $4.25 million

But will the latest gene therapy suffer the curse of the costliest drug?

Stay connected

Illustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at with a list of newsletters you’d like to receive.