Death, according to members of the longevity movement, can and should be delayed by fighting the process of human ageing. Some hope it could be ‘defeated’ entirely.
Backed by billionaires and propelled to prominence by high-profile figurehead Bryan Johnson, many of the processes and techniques employed in attempts to ‘live forever’ sit within experimental medicine and less-proven fields. But some of the most effective methods that are likely to significantly lengthen human lifespans are in development at biomedical engineering firms and research laboratories.
An elixir of ever-lasting life seems unlikely to ever leave the pages of fiction – but engineering approaches could soon start to extend the average human lifetime.
Printed organs
Online longevity regimens detail the technology already used by Johnson and his acolytes, including red light therapy devices and temperature-controlled beds to maximise sleep quality. Other large bits of kit include Dexa scanners, which measure bone health, muscle mass and other factors, and hyperbaric chambers for oxygen therapy.
Tracking and optimising biometrics is another core tenet of the longevity movement, so wearables such as the Oura Ring 4, which tracks metrics including heart health, stress and metabolic health, are also frequently discussed.
These technologies are already well developed, and many similar products will likely enter the market as those who can afford it seek to delay the inevitable. But truly ‘defeating death’ will require more radical solutions, several of which are the focus of cutting-edge biomedical research.
“We have a good sense of understanding of what the fundamental mechanisms of ageing are,” says Professor Richard Faragher, past chair of the British Society for Research on Ageing and member of the scientific advisory board of the Longevity Vision Fund, which seeks to support early-stage companies with a mission to improve healthy human longevity. Sectors covered by the fund include the use of AI in healthcare, early diagnostics and drug delivery platforms.
Faragher’s work focuses on cellular senescence, in which cells stop dividing but do not die. Accumulation of these cells is a major cause of ageing.
Some evidence shows that human ageing processes are probably responsible for the failure of medical technology such as bioartificial livers, Faragher says. The external devices use functioning liver cells to temporarily replace critical functions of the human organ.
“This is an area within bioengineering that is rather under-recognised,” he says. “We’re going to have to think much more carefully about how to engineer these things for an ageing population.”
In future, bioprinting – using additive manufacturing technology to print new organs using scaffolds and cell-containing bio-inks – could offer an even more advanced approach. Being developed at research institutes around the world, such as Wake Forest University in North Carolina, bioprinted organs made using patients’ own cells could one day offer accessible replacements for failing organs.
Many challenges remain to be solved, however, including ensuring delivery of nutrients to the cells throughout an artificial organ. Considerable uncertainty remains around the approach, according to Faragher. “An artificially printed 3D liver may be a fascinating research project, but it’s a hell of a long way from something that’s useful,” says Faragher, who is also a professor of biogerontology at the University of Brighton.
“Do I think there’s a future for this stuff? Yes. Do I think there’s an assured route by which it goes on? No… there are innumerable false starts.”
Brain-computer interfaces
Building new livers or hearts is one thing – replacing the human brain, often described as the most complex known object in the universe, is quite another. It is nonetheless being explored, such as in the work of Jean Hébert at the US Advanced Research Projects Agency for Health, who reportedly aims to replace brain tissue bit by bit.
Intrinsically tied to health and ageing, other biomedical engineering approaches could have a more immediate impact on brain functionality and ability to communicate with the rest of the body. Brain-computer interfaces (BCI), for example, are already restoring abilities for those who have lost them.
There are two main types of BCI, says Dr Ian Daly, senior lecturer in BCI and AI at the University of Essex: invasive and non-invasive. Elon Musk’s Neuralink implants are an invasive example, requiring surgery and implantation of a set of electrodes inside the brain. These are currently designed for people with very severe levels of disability, Daly says, such as near-complete locked-in syndrome. The devices can control robotic limbs or voice technology.
Non-invasive BCI use neuroimaging methods such as electroencephalogram (EEG) or neuro-infrared spectroscopy. Much safer than invasive options, according to Daly, they can be used far more widely. Applications also include communication or rehabilitation after brain injuries or stroke. The decoding accuracy for individual actions is slightly lower, however: 70-80%, compared with roughly 90%.
The devices record and process signals from the brain, restoring control over functions. “If you have a stroke that affects your ability to control, say, your arm, then we can use the BCI to retrain the unaffected parts of the brain to learn to control that limb,” Daly says.
“BCI can be applicable as a sort of medical tool to help rehabilitate and help to provide medical assistance to people who suffer from the sort of disabilities that are more likely to happen as we age.”
While some longevity enthusiasts might hope for even more ambitious applications of BCI technology, such as ‘downloading’ the brain to preserve consciousness after the body has died, Daly says such concepts are a long way away.
“We’ve all seen sci-fi movies like The Matrix, where they have very sophisticated fantasies of what a BCI could be,” he says. “We’re not there yet. We’re a long, long, long way from that at the moment…
“What we do now is we’re decoding discrete actions. So if you want to turn your wheelchair to the left or the right, we can do that, right? If you want to upload your innermost thoughts or your consciousness or your sense of self – no, no, that’s in the realm of sci-fi still.”
Meanwhile, there are some practical challenges that remain to be solved to optimise current devices. Work is ongoing to separate neural signals from noise and to build improved AI systems to decode the signal more accurately.
“With invasive systems, we have issues with biocompatibility and rejection of the implant. We have issues around managing infection, managing risk… how do you manage that the system effectively remains operational for years and years?” Daly asks.
“We also have issues of coverage. So implanted systems, they are typically small chips that we implant in one area of the brain, and that allows us to do one thing usually. So if we implant in the motor cortex, we can decode motor actions. In speech cortex, we can decode speech – but it’s just a small part of the brain that we’re able to decode. So there are issues with sort of broad coverage.”
Deep freeze
Looking ahead, other longevity-enhancing technologies could include nanobots for targeted drug delivery or cancer treatment, and cryonics, with wealthy adopters hoping their frozen bodies could one day be returned to life. The technology is still unproven in humans, despite recent small-scale success with mouse brain tissue.
Despite many of the approaches being fraught with moral and ethical issues, billionaire backing means they are likely to develop significantly in the coming decades. Of course, death can only truly be ‘defeated’ if the technologies are available for more people than the extremely wealthy – and that is likely to take considerably longer.
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