New Tests Measure Your Body’s Biological Age, Offering a Glimpse into the Future of Health Care
What if a simple blood test revealed how fast you're aging, and this meant more to you and your insurance company than the number of candles on your birthday cake?
The question of why individuals thrive or decline has loomed large in 2020, with COVID-19 harming people of all ages, while leaving others asymptomatic. Meanwhile, scientists have produced new measures, called aging clocks, that attempt to predict mortality and may eventually affect how we perceive aging.
Take, for example, "senior" athletes who perform more like 50-year-olds. But people over 65 are lumped into one category, whether they are winning marathons or using a walker. Meanwhile, I'm entering "middle age," a label just as vague. It's frustrating to have a better grasp on the lifecycle of my phone than my own body.
That could change soon, due to clock technology. In 2013, UCLA biostatistician Steven Horvath took a new approach to an old carnival trick, guessing people's ages by looking at epigenetics: how chemical compounds in our cells turn genetic instructions on or off. Exercise, pollutants, and other aspects of lifestyle and environment can flip these switches, converting a skin cell into a hair cell, for example. Then, hair may sprout from your ears.
Horvath's epigenetic clock approximated age within just a few years; an above-average estimate suggested fast aging. This "basically changed everything," said Vadim Gladyshev, a Harvard geneticist, leading to more epigenetic clocks and, just since May, additional clocks of the heart, products of cell metabolism, and microbes in a person's mouth and gut.
Machine learning is fueling these discoveries. Scientists send algorithms hunting through jungles of health data for factors related to physical demise. "Nothing in [the aging] industry has progressed as much as biomarkers," said Alex Zhavoronkov, CEO of Deep Longevity, a pioneer in learning-based clocks.
Researchers told LeapsMag that this tech could help identify age-related vulnerabilities to diseases—including COVID-19—and protective drugs.
Clocking disease vulnerability
In July, Yale researcher Morgan Levine found people were more likely to be hospitalized and die from COVID-19 if their aging clocks were ticking ahead of their calendar years. This effect held regardless of pre-existing conditions.
The study used Levine's biological aging clock, called PhenoAge, which is more accurate than previous versions. To develop it, she looked at data on health indices over several decades, focusing on nine hallmarks of aging—such as inflammation—that correspond to when people die. Then she used AI to find which epigenetic patterns in blood samples were strongly associated with physical aging. The PhenoAge clock reads these patterns to predict biological age; mortality goes up 62 percent among the fastest agers.
The cocktail, aimed at restoring immune function, reversed age by an average of 2.5 years, according to an epigenetic clock measurement taken before and after the intervention.
Because PhenoAge links chronic inflammation to aging and vulnerability, Levine proposed treating "inflammaging" to counter COVID-19.
Gladyshev reported similar findings, and Nir Barzilai, director of the Institute of Aging Research at Albert Einstein College of Medicine, agreed that biological age deserves greater focus. PhenoAge is an important innovation, he said, but most precise when measuring average age across large populations. Until clocks—including his blood protein version—account for differences in how individuals age, "Multi-morbidity is really the major biomarker" for a given person. Barzilai thinks individuals over 65 with two or more diseases are biologically older than their chronological age—about half the population in this study.
He believes COVID-19 efforts aren't taking stock of these differences. "The scientists are living in silos," he said, with many unaware aging has a biology that can be targeted.
The missed opportunities could be profound, especially for lower-income communities with disproportionately advanced aging. Barzilai has read eight different observational studies finding decreased COVID-19 severity among people taking metformin, the diabetes drug, which is believed to slow down the major hallmarks of biological aging, such as inflammation. Once a vaccine is identified, biologically older people could supplement it with metformin, but the medical establishment requires lengthy clinical trials. "The conservatism is taking over in days of war," Barzilai said.
Drug benefits on time
Clocks, once validated, could gauge drug effectiveness against age-related diseases quicker and cheaper than trials that track health outcomes over many years, expediting FDA approval of such therapies. For this to happen, though, the FDA must see evidence that rewinding clocks or improving related biomarkers leads to clinical benefits for patients. Researchers believe that clinical applications for at least some of these clocks are five to 10 years away.
Progress was made in last year's TRIIM trial, run by immunologist Gregory Fahy at Stanford Medical Center. People in their 50s took growth hormone, metformin and another diabetes drug, dehydroepiandrosterone, for 12 months. The cocktail, aimed at restoring immune function, reversed age by an average of 2.5 years, according to an epigenetic clock measurement taken before and after the intervention. Don't quit your gym just yet; TRIIM included just nine Caucasian men. A follow-up with 85 diverse participants begins next month.
But even group averages of epigenetic measures can be questionable, explained Willard Freeman, a researcher with the Reynolds Oklahoma Center on Aging. Consider this odd finding: heroin addicts tend to have younger epigenetic ages. "With the exception of Keith Richards, I don't think heroin is a great way to live a long healthy life," Freeman said.
Such confounders reveal that scientists—and AI—are still struggling to unearth the roots of aging. Do clocks simply reflect damage, mirrors to show who's the frailest of them all? Or do they programmatically drive aging? The answer involves vast complexity, like trying to deduce the direct causes of a 17-car pileup on a potholed road in foggy conditions. Except, instead of 17 cars, it's millions of epigenetic sites and thousands of potential genes, RNA molecules and blood proteins acting on aging and each other.
Because the various measures—epigenetics, microbes, etc.—capture distinct aging dimensions, an important goal is unifying them into one "mosaic of biological ages," as Levine called it. Gladyshev said more datasets are needed. Just yesterday, though, Zhavoronkov launched Deep Longevity's groundbreaking composite of metrics to consumers – something that was previously available only to clinicians. The iPhone app allows users to upload their own samples and tracks aging on multiple levels – epigenetic, behavioral, microbiome, and more. It even includes a deep psychological clock asking if people feel as old as they are. Perhaps Twain's adage about mind over matter is evidence-backed.
Zhavoronkov appeared youthful in our Zoom interview, but admitted self-testing shows an advanced age because "I do not sleep"; indeed, he'd scheduled me at midnight Hong Kong time. Perhaps explaining his insomnia, he fears economic collapse if age-related diseases cost the global economy over $30 trillion by 2030. Rather than seeking eternal life, researchers like Zhavoronkov aim to increase health span: fully living our final decades without excess pain and hospital bills.
It's also a lucrative sales pitch to 7.8 billion aging humans.
Get your bio age
Levine, the Yale scientist, has partnered with Elysium Health to sell Index, an epigenetic measure launched in late 2019, direct to consumers, using their saliva samples. Elysium will roll out additional measures as research progresses, starting with an assessment of how fast someone is accumulating cells that no longer divide. "The more measures to capture specific processes, the more we can actually understand what's unique for an individual," Levine said.
Another company, InsideTracker, with an advisory board headlined by Harvard's David Sinclair, eschews the quirkiness of epigenetics. Its new InnerAge 2.0 test, announced this month, analyzes 18 blood biomarkers associated with longevity.
"You can imagine payers clamoring to charge people for costs with a kind of personal responsibility to them."
Because aging isn't considered a disease, consumer aging tests don't require FDA approval, and some researchers are skeptical of their use in the near future. "I'm on the fence as to whether these things are ready to be rolled out," said Freeman, the Oklahoma researcher. "We need to do our traditional experimental study design to [be] confident they're actually useful."
Then, 50-year-olds who are biologically 45 may wait five years for their first colonoscopy, Barzilai said. Despite some forerunners, clinical applications for individuals are mostly prospective, yet I was intrigued. Could these clocks reveal if I'm following the footsteps of the super-agers? Or will I rack up the hospital bills of Zhavoronkov's nightmares?
I sent my blood for testing with InsideTracker. Fearing the worst—an InnerAge accelerated by a couple of decades—I asked thought leaders where this technology is headed.
Insurance 2030
With continued advances, by 2030 you'll learn your biological age with a glance at your wristwatch. You won't be the only monitor; your insurance company may send an alert if your age goes too high, threatening lost rewards.
If this seems implausible, consider that life insurer John Hancock already tracks a VitalityAge. With Obamacare incentivizing companies to engage policyholders in improving health, many are dangling rewards for fitness. BlueCross BlueShield covers 25 percent of InsideTracker's cost, and UnitedHealthcare offers a suite of such programs, including "missions" for policyholders to lower their Rally age. "People underestimate the amount of time they're sedentary," said Michael Bess, vice president of healthcare strategies. "So having this technology to drive positive reinforcement is just another way to encourage healthy behavior."
It's unclear if these programs will close health gaps, or simply attract customers already prioritizing fitness. And insurers could raise your premium if you don't measure up. Obamacare forbids discrimination based on pre-existing conditions, but will accelerated age qualify for this protection?
Liz McFall, a sociologist at the University of Edinburgh, thinks the answer depends on whether we view aging as controllable. "You can imagine payers clamoring to charge people for costs with a kind of personal responsibility to them," she said.
That outcome troubles Mark Rothstein, director of the Institute of Bioethics at the University of Louisville. "For those living with air pollution and unsafe water, in food deserts and where you can't safely exercise, then [insurers] take the results in terms of biological stressors, now you're adding insult to injury," he said.
Government could subsidize aging clocks and interventions for older people with fewer resources for controlling their health—and the greatest room for improving their epigenetic age. Rothstein supports that policy, but said, "I don't see it happening."
Bio age working for you
2030 again. A job posting seeks a "go-getter," so you attach a doctor's note to your resume proving you're ten years younger than your chronological age.
This prospect intrigued Cathy Ventrell-Monsees, senior advisor at the Equal Employment Opportunity Commission. "Any marker other than age is a step forward," she said. "Age simply doesn't determine any kind of cognitive or physical ability."
What if the assessment isn't voluntary? Armed with AI, future employers could surveil a candidate's biological age from their head-shot. Haut.ai is already marketing an uncannily accurate PhotoAgeClock. Its CEO, Anastasia Georgievskaya, noted this tech's promise in other contexts; it could help people literally see the connection between healthier lifestyles and looking young and attractive. "The images keep people quite engaged," she told me.
Updating laws could minimize drawbacks. Employers are already prohibited from using genetic information to discriminate (think 23andMe). The ban could be extended to epigenetics. "I would imagine biomarkers for aging go a similar path as genetic nondiscrimination," said McFall, the sociologist.
Will we use aging clocks to screen candidates for the highest office? Barzilai, the Albert Einstein College of Medicine researcher, believes Trump and Biden have similar biological ages. But one of Barzilai's factors, BMI, is warped by Trump miraculously getting taller. "Usually people get shorter with age," Barzilai said. "His weight has been increasing, but his BMI stays the same."
As for my bio age? InnerAge suggested I'm four years younger—and by boosting my iron levels, the program suggests, I could be younger still.
We need standards for these tests, and customers must understand their shortcomings. With such transparency, though, the benefits could be compelling. In March, Theresa Brown, a 44-year-old from Kansas, learned her InnerAge was 57.2. She followed InsideTracker's recommendations, including regular intermittent fasting. Retested five months later, her age had dropped to 34.1. "It's not that I guaranteed another 10 or 20 years to my life. It's that it encourages me. Whether I really am or not, I just feel younger. I'll take that."
Which leads back to Zhavoronkov's psychological clock. Perhaps lowering our InnerAges can be the self-fulfilling prophesy that helps Theresa and me age like the super-athletes who thrive longer than expected. McFall noted the power of simple, sufficiently credible goals for encouraging better health. Think 10,000 steps per day, she said.
Want to be 34 again? Just do it.
Yet, many people's budgets just don't allow gym memberships, nutritious groceries, or futuristic aging clocks. Bill Gates cautioned we overestimate progress in the next two years, while underestimating the next ten. Policies should ensure that age testing and interventions are distributed fairly.
"Within the next 5 to 10 years," said Gladyshev, "there will be drugs and lifestyle changes which could actually increase lifespan or healthspan for the entire population."
This man spent over 70 years in an iron lung. What he was able to accomplish is amazing.
It’s a sight we don’t normally see these days: A man lying prone in a big, metal tube with his head sticking out of one end. But it wasn’t so long ago that this sight was unfortunately much more common.
In the first half of the 20th century, tens of thousands of people each year were infected by polio—a highly contagious virus that attacks nerves in the spinal cord and brainstem. Many people survived polio, but a small percentage of people who did were left permanently paralyzed from the virus, requiring support to help them breathe. This support, known as an “iron lung,” manually pulled oxygen in and out of a person’s lungs by changing the pressure inside the machine.
Paul Alexander was one of several thousand who were infected and paralyzed by polio in 1952. That year, a polio epidemic swept the United States, forcing businesses to close and polio wards in hospitals all over the country to fill up with sick children. When Paul caught polio in the summer of 1952, doctors urged his parents to let him rest and recover at home, since the hospital in his home suburb of Dallas, Texas was already overrun with polio patients.
Paul rested in bed for a few days with aching limbs and a fever. But his condition quickly got worse. Within a week, Paul could no longer speak or swallow, and his parents rushed him to the local hospital where the doctors performed an emergency procedure to help him breathe. Paul woke from the surgery three days later, and found himself unable to move and lying inside an iron lung in the polio ward, surrounded by rows of other paralyzed children.
Hospitals were commonly filled with polio patients who had been paralyzed by the virus before a vaccine became widely available in 1955. Associated Press
Paul struggled inside the polio ward for the next 18 months, bored and restless and needing to hold his breath when the nurses opened the iron lung to help him bathe. The doctors on the ward frequently told his parents that Paul was going to die.But against all odds, Paul lived. And with help from a physical therapist, Paul was able to thrive—sometimes for small periods outside the iron lung.
The way Paul did this was to practice glossopharyngeal breathing (or as Paul called it, “frog breathing”), where he would trap air in his mouth and force it down his throat and into his lungs by flattening his tongue. This breathing technique, taught to him by his physical therapist, would allow Paul to leave the iron lung for increasing periods of time.
With help from his iron lung (and for small periods of time without it), Paul managed to live a full, happy, and sometimes record-breaking life. At 21, Paul became the first person in Dallas, Texas to graduate high school without attending class in person, owing his success to memorization rather than taking notes. After high school, Paul received a scholarship to Southern Methodist University and pursued his dream of becoming a trial lawyer and successfully represented clients in court.
Paul Alexander, pictured here in his early 20s, mastered a type of breathing technique that allowed him to spend short amounts of time outside his iron lung. Paul Alexander
Paul practiced law in North Texas for more than 30 years, using a modified wheelchair that held his body upright. During his career, Paul even represented members of the biker gang Hells Angels—and became so close with them he was named an honorary member.Throughout his long life, Paul was also able to fly on a plane, visit the beach, adopt a dog, fall in love, and write a memoir using a plastic stick to tap out a draft on a keyboard. In recent years, Paul joined TikTok and became a viral sensation with more than 330,000 followers. In one of his first videos, Paul advocated for vaccination and warned against another polio epidemic.
Paul was reportedly hospitalized with COVID-19 at the end of February and died on March 11th, 2024. He currently holds the Guiness World Record for longest survival inside an iron lung—71 years.
Polio thankfully no longer circulates in the United States, or in most of the world, thanks to vaccines. But Paul continues to serve as a reminder of the importance of vaccination—and the power of the human spirit.
““I’ve got some big dreams. I’m not going to accept from anybody their limitations,” he said in a 2022 interview with CNN. “My life is incredible.”
When doctors couldn’t stop her daughter’s seizures, this mom earned a PhD and found a treatment herself.
Twenty-eight years ago, Tracy Dixon-Salazaar woke to the sound of her daughter, two-year-old Savannah, in the midst of a medical emergency.
“I entered [Savannah’s room] to see her tiny little body jerking about violently in her bed,” Tracy said in an interview. “I thought she was choking.” When she and her husband frantically called 911, the paramedic told them it was likely that Savannah had had a seizure—a term neither Tracy nor her husband had ever heard before.
Over the next several years, Savannah’s seizures continued and worsened. By age five Savannah was having seizures dozens of times each day, and her parents noticed significant developmental delays. Savannah was unable to use the restroom and functioned more like a toddler than a five-year-old.
Doctors were mystified: Tracy and her husband had no family history of seizures, and there was no event—such as an injury or infection—that could have caused them. Doctors were also confused as to why Savannah’s seizures were happening so frequently despite trying different seizure medications.
Doctors eventually diagnosed Savannah with Lennox-Gaustaut Syndrome, or LGS, an epilepsy disorder with no cure and a poor prognosis. People with LGS are often resistant to several kinds of anti-seizure medications, and often suffer from developmental delays and behavioral problems. People with LGS also have a higher chance of injury as well as a higher chance of sudden unexpected death (SUDEP) due to the frequent seizures. In about 70 percent of cases, LGS has an identifiable cause such as a brain injury or genetic syndrome. In about 30 percent of cases, however, the cause is unknown.
Watching her daughter struggle through repeated seizures was devastating to Tracy and the rest of the family.
“This disease, it comes into your life. It’s uninvited. It’s unannounced and it takes over every aspect of your daily life,” said Tracy in an interview with Today.com. “Plus it’s attacking the thing that is most precious to you—your kid.”
Desperate to find some answers, Tracy began combing the medical literature for information about epilepsy and LGS. She enrolled in college courses to better understand the papers she was reading.
“Ironically, I thought I needed to go to college to take English classes to understand these papers—but soon learned it wasn’t English classes I needed, It was science,” Tracy said. When she took her first college science course, Tracy says, she “fell in love with the subject.”
Tracy was now a caregiver to Savannah, who continued to have hundreds of seizures a month, as well as a full-time student, studying late into the night and while her kids were at school, using classwork as “an outlet for the pain.”
“I couldn’t help my daughter,” Tracy said. “Studying was something I could do.”
Twelve years later, Tracy had earned a PhD in neurobiology.
After her post-doctoral training, Tracy started working at a lab that explored the genetics of epilepsy. Savannah’s doctors hadn’t found a genetic cause for her seizures, so Tracy decided to sequence her genome again to check for other abnormalities—and what she found was life-changing.
Tracy discovered that Savannah had a calcium channel mutation, meaning that too much calcium was passing through Savannah’s neural pathways, leading to seizures. The information made sense to Tracy: Anti-seizure medications often leech calcium from a person’s bones. When doctors had prescribed Savannah calcium supplements in the past to counteract these effects, her seizures had gotten worse every time she took the medication. Tracy took her discovery to Savannah’s doctor, who agreed to prescribe her a calcium blocker.
The change in Savannah was almost immediate.
Within two weeks, Savannah’s seizures had decreased by 95 percent. Once on a daily seven-drug regimen, she was soon weaned to just four, and then three. Amazingly, Tracy started to notice changes in Savannah’s personality and development, too.
“She just exploded in her personality and her talking and her walking and her potty training and oh my gosh she is just so sassy,” Tracy said in an interview.
Since starting the calcium blocker eleven years ago, Savannah has continued to make enormous strides. Though still unable to read or write, Savannah enjoys puzzles and social media. She’s “obsessed” with boys, says Tracy. And while Tracy suspects she’ll never be able to live independently, she and her daughter can now share more “normal” moments—something she never anticipated at the start of Savannah’s journey with LGS. While preparing for an event, Savannah helped Tracy get ready.
“We picked out a dress and it was the first time in our lives that we did something normal as a mother and a daughter,” she said. “It was pretty cool.”