Maybe we’re all just batteries. That’s the bad news for Keanu Reeves’ Neo, who wakes up from a chemically-induced slumber and discovers he’s nothing more than a pack of double-A’s connected to a massive power station run by evil robot overlords in the dystopian sci-fi film “The Matrix.”
But what if the power potential of human electric current wasn’t so post-apocalyptic? As the International Energy Agency notes, global demand for power rose 2.3% in 2018, which represents the biggest increase in the last decade. Ever since Ben Franklin first decided that flying kites in dangerous weather was solid scientific practice, humans have been finding new ways to use electricity — and discovering that demand never stops.
The bad news? You’re no coppertop. The better news? Bioelectricity is essential to life — and may drive the future of human development.
A Shocking History
Harvesting electricity from human activity is nothing new. As Knowable Magazine notes, breathing can produce more than 0.80 watts, body heat can generate up to 4.8 watts, and the motion of your arms creates a stunning 60 watts of power.
But the notion of electricity as fundamental to biological life isn’t quite so clear-cut. According to Quartz, while there were some experiments measuring human electrical currents in the mid-1920s, it’s wasn’t until 1949 that Alan Hodgkin and Andrew Huxley identified the movement of ions across cell nerve membranes. The pair took home a Nobel Prize for their work, but this electric revolution was quickly outpaced by the double-helix discovery of DNA. For decades, genes became the best-fit scientific foundation for biology, while electricity research was short-circuited.
Then, in 1976, Erwin Neher and Bert Sakmann developed a tool capable of circumventing bioelectricity’s biggest problem: studying ion movements without killing their cellular transport mediums. And later, in 2012, Richard Nuccitelli created a device sensitive and subtle enough to track human electric currents on skin, and discovered that, when skin cells are wounded, they emit an “injury current” that calls for help from other cells. The larger the wound, the bigger the current — and the current decreases with age. Other work found that charges inside embryo cells significantly affected development. As NOVA states, “Researchers overwhelmingly agree that bioelectric currents are essential to nerve and muscle function.”
With the human nervous system constantly generating a fluctuating electric current, why can’t we all just plug in and power up? It all comes down to the two halves of electric potential: positive and negative charges.
The electricity we’re most familiar with — the kind Franklin flew kites for and that powers our smartphones, dishwashers and light bulbs — depends on the flow of negatively-charged electrons to produce a current. Meanwhile, in our bodies, it’s the movement of positively-charged ions — such as potassium, sodium and calcium — passing through cell membranes that create electric potential. And while this variable voltage is essential to keep hearts beating, limbs moving and minds functioning, it’s not great for typical electrical applications. For example, when animal cells take in sodium and chloride ions and discharge potassium ions, the result is a voltage between -40 to -80 mV across membranes, significantly less than a single watch battery.
However, as it turns out, human electric current offers significant potential for internal applications.
The biggest potential for human-produced power? Improved healing. Studies published in the journal Advances in Wound Care have shown that supplementing the body’s electric current with outside electrical stimulation can help to reduce the recovery time needed for bedsores, which are some of the most difficult wounds to mitigate, let alone fully heal. Similar work has shown improvements in healing bone fractures.
Next on the list? Cancer. While research in the 1920s demonstrated a connection between changing electric gradients and cancerous tumors, cell mutations are the most commonly cited cause of cancer concerns. Now, there’s speculation that misregulation of electric currents may lead to cellular communication challenges — in effect, cells “forget” they’re part of a larger network and begin acting selfishly by hoarding resources and growing out of control. Research from the University of Nottingham found that biologically-generated currents underpin specific cancer cell behaviors, and new techniques using a combination of gene therapy and light-activated ion channels have seen success treating cancer in tadpoles.
However, despite steady progress, challenges remain. Human genomes are far more complex than those of rats or tadpoles, and gene therapies face significant regulatory challenges. Electric treatments for wound healing also struggle with standardization — how long should currents be applied to wounds for maximum effect without causing secondary damage? At what voltage? Using what type of device? Is alternating current (AC) or direct current (DC) safer? More effective?
The result is a kind of cautious optimism. While bioelectric benefits are grounded in solid science, more testing and research is necessary to standardize and streamline medical processes.
The Ion Imperative
Bioelectric research offers the tantalizing potential to tap the inherent power of the human nervous system, but we’re not there yet.
Still, there’s good reason to be optimistic. Mike Levin of Tufts University, whose lab is on the leading edge of human electric current research, puts it simply: “Understanding the bioelectricity, biomechanics, and transcriptional circuits that allow cells to cooperate toward large-scale goals is the key to regenerative medicine, birth defects, cancer reprogramming, aging, synthetic bioengineering, and even new AI.”
Put simply? We’re not batteries — thanks to positive bioelectric potential, we’re even better.
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