Biological age tests: Should you get one?

If you’ve heard of billionaire Bryan Johnson, you’ve likely encountered the phrase “bio age testing.”

Johnson, the subject of the Netflix documentary Don’t Die, says he’s on a quest to achieve the lowest possible “biological age” (also known as bio age).

He reportedly spends millions each year on anti-aging treatments—dozens of daily supplements, weekly acid peels for his skin, injections to boost collagen production, hyperbaric oxygen therapy, and plasma infusions extracted from his 17-year-old son’s body.

To determine what’s working, Johnson has undergone numerous tests to assess his bio age. Johnson says these tests show his age is now 5.1 years younger than when he embarked on his anti-aging quest.

Apparently, he’s aging in reverse.

Granted, not everyone’s buying it. A New York Times exposé, for example, claims Johnson’s biological age, in reality, has increased by 10 years.¹

Still, Johnson’s “don’t die” crusade is gaining traction.

Bio age tests are a frequent topic on popular podcasts by Peter Attia, Joe Rogan, and Andrew Huberman. Google “bio age testing” and you’ll see dozens of ads for mail-order blood or urine testing kits that claim to reveal your biological age, pace of aging, and more. With prices tumbling into affordability, it’s natural to wonder…

Should you or your client sign up for bio age testing?

If so, which test is best? Just as importantly, what should you do with the information?

In this story, you’ll learn:

What is your bio age?

Your biological age (bio age) refers to how your cells function. It’s not necessarily the same as your chronological age, which refers to the number of candles on your birthday cake.

For example, let’s say Chang, a 50-year-old man, works at a desk, spends his free time in front of the TV, lives in the most polluted city in the world, eats a candy bar for lunch, and smokes. On the other hand, Jabari, a different 50-year-old man, hits the gym several times a week, lives in the mountains, doesn’t smoke, relishes his five servings of veggies a day, meditates, and spends most evenings in his garden.

Genetics aside, you’d be wise to wager that Jabari’s bio age is younger than Chang’s.

How do these tests measure bio age?

Bio age testing kits measure one or more biological markers of aging, also known as biomarkers.

For example, some tests focus on the size of your telomeres, the protective caps at the ends of chromosomes. Others measure DNA methylation, a physiological process that chemically alters DNA.

Once a company isolates and measures these markers from your blood or urine, it plugs the bio data into a formula that calculates your bio age.

However, if you see a doctor with any regularity, you’re likely already tracking some biomarkers of aging. For example, biomarkers such as blood pressure, cholesterol levels, and blood glucose can help predict your risk of future cardiovascular disease, a leading cause of premature death.

What’s the point of biomarker testing?

Biomarker testing can help you monitor your wellness proactively rather than waiting for disease symptoms to appear.

For some, it also serves as a motivator. If you learn you have the bones of someone 20 years older, this may give you the nudge you need to start strength training consistently.

In addition, biomarkers provide objective data, allowing you to track and evaluate various health-related actions quantitatively. By monitoring your blood pressure, you might learn that consistent exercise helps, but your late-afternoon energy drink does the opposite.

5 FREE biomarker tests

You don’t have to be a billionaire (or even a millionaire) to track biomarkers of aging.

In this section, we’ll cover several massively underappreciated, scientifically validated tests you can use to gain insight into your bio age—for FREE.

Before scientists developed high-tech blood-based bio age tests, researchers used these free tests to calculate the pace of aging in the people they studied.

FREE biomarker test #1: Get off the floor

People who are fitter and stronger tend to live longer.²

That’s because muscles do more than just move us around. They also secrete anti-inflammatory substances, help to regulate blood sugar, slow cellular aging, protect the lining of the arteries, and more. All this helps reduce the risk of age-related diseases, such as type 2 diabetes, high blood pressure, and heart disease, a phenomenon we explore in our article, The New Science of Muscle.

Related to strength, your ability to balance is also key. If you’re middle-aged or older and can’t stand on one foot for at least 10 seconds, your risk of dying in the next seven years is double that of someone who can stand for longer, according to a study of 1,700 people.³

The Sitting-Rising Test (SRT) is one way to assess both strength and balance at the same time.

People with low scores on this test have a higher risk of dying from cardiovascular disease, according to a 12-year study of 4,200 adults between the ages of 46 and 75.⁴

▶ How to measure it

Lower yourself to the floor with your legs in a crisscross position. Then, with your legs in the same position, stand back up. As you stand, notice if you must use a part of your body—hand, shin, knee—as leverage.

To score yourself, start with 10 points. Then, for each body part you used to stand, deduct a point. Subtract a half point if you became unsteady or lost your balance.

Keep in mind that this (and other tests) serve as a proxy for your fitness. A low score indicates that your balance and coordination, muscle strength and power, and mobility may all require some attention.

FREE biomarker test #2: Squeeze a ball

Like the SRT test, your grip strength provides insight into your overall fitness. If the muscles in your hands are weak, the muscles throughout your body are more likely to be weak, too.

Poor grip strength can also predict future muscle weakness. In one study, people with a weak grip were more likely to walk slowly and be unable to rise from a chair, complete rigorous housework, or climb a flight of steps 25 years later.⁵

Low grip strength has also been associated with:⁶

• Low bone mineral density
• Increased risk of falls
• Poor nutritional status
• Depression
• Poor sleep, cognitive function, and/or quality of life
• Increased risk of heart disease, cancer, and premature mortality

According to one study, grip strength was a better indicator of longevity (or lack thereof) than blood pressure.⁷

▶ How to measure it

Grab a standard tennis ball, and squeeze as hard as you can, for as long as you can.

If you can manage 15 to 30 seconds before your grip fatigues, you’re doing fine. Ninety seconds puts you well above average—anything over 90 ranks you solidly in the upper-third percentile.

If you’re below 15, keep in mind that this test is also just one indicator of your overall strength. (And squeezing balls to improve grip strength without training the rest of your body is unlikely to make significant improvements in your overall health and fitness.)

A hand-held dynamometer—available for use at most occupational therapists’ and some gyms—can also test grip strength. (If you’re willing to shell out some cash, you can buy your own for somewhere between $100 and $500.)

FREE biomarker test #3: Stand on one foot

An ability to balance on one foot for an extended period can help reduce your risk of falls, one of the leading causes of injury-related death among older adults.

In addition, many different bodily systems—the eyes, inner ear, skeletal muscles, and brain—must work together to help you stay upright.

Conditions like diabetes, heart disease, and cancer can all affect balance. As a result, an inability to stand on one foot can serve as a warning sign for eroding health and fitness.⁸

▶ How to measure it

Stand near a wall or chair for safety. Keep your eyes open and hands on your hips. Then, lift your dominant leg and start timing yourself. Once you put your foot down, stop the clock. Repeat the test with your non-dominant leg.

Once you have your times, compare them to the following averages, from a study out of Duke University, to see how you did compared to your age-matched peers.⁹

FREE biomarker test #4: How you feel

Sometimes you know why you’re tired, such as the morning after binge-watching the last few episodes of a thriller. Once you catch up on your sleep, the weariness lifts.

That’s not the same thing as fatigue, which describes persistent exhaustion that worsens over time and interferes with life. In addition to feeling physically tired, someone who’s fatigued feels mentally dull and emotionally exhausted.

Think of fatigue as an early sign that something’s off, especially if you don’t know the cause.

Let’s say you’ve already ruled out the usual suspects like too much caffeine, dehydration, too much alcohol, medication side effects, chronic stress, or too much or too little exercise. What’s left is likely a sleep disorder or a developing health problem such as anemia, obesity, depression, cancer, or diabetes, to name a few.

If you’re 60 or older, fatiguability—or how worn out you feel after an activity—can also predict longevity.

According to research out of the University of Pittsburgh Medical Center, the higher someone scores in fatiguability, the higher their risk of death in the future.¹⁰ Other research has linked high fatiguability with declines in gait speed, walking ability, and other tests of fitness.¹¹

▶ How to measure it

To measure fatigability, use a tool called the Pittsburgh Fatigability Scale. Using a 0 (no fatigue) to 5 (extreme fatigue) scale, rate how fatigued you think you would feel after completing the following activities:

If you score less than 15, you’re doing well. Scores between 15 and 24 are a warning sign. Anything 25 and above is regarded as severe, and worth mentioning to your healthcare professional.¹²

FREE biomarker test #5: Body composition

Despite popular belief, both too little and too much body fat can influence health for the worse, as we explore in our infographic, Is body fat good or bad for you?

Your muscle mass also plays a role, which is why someone’s body composition matters more than their weight.

The gold standard methods that estimate body composition—underwater weighing, air displacement (Bod Pod), and dual-energy X-ray absorptiometry (DEXA)—certainly aren’t free.

However, a recent study determined that a good old-fashioned (and cheap) tape measure can provide a comparably accurate estimate of body composition.¹³

▶ How to measure it

To use a tape measure to keep track of your body fat percentage, measure:

• The widest part of your neck
• The narrowest part of your waist (For some people, this will be at the navel. For others, it might be slightly above the navel)
• The widest part of your hips

Ensure the tape is snug but not so tight that it cuts into the skin. Once you have your measurements, plug those numbers—along with your age, sex, height, and weight—into our FREE Body Fat Calculator, which will take it from there.

Doctor-approved biomarker tests

Depending on where you live in the world, the following tests may not be free. However, as part of routine preventative care, your insurance might cover them.

Doctor-approved test #1: Blood panel

If your primary care doctor recommends yearly blood work, it’s for good reason.

By keeping tabs on several blood markers, you can see if your health is trending toward type 2 diabetes or heart disease, both leading causes of premature mortality.

Many blood markers can also be influenced relatively quickly (within 6 to 12 weeks) through lifestyle changes, supplement protocols, or medications. This makes them practical tools for monitoring whether various lifestyle or medical modifications are working.

▶ How to measure it

If you’re not already doing so, consider having the following blood markers tested annually. Then, talk to your health care professional about what your numbers mean. They might use the following numbers, along with your blood pressure, to calculate a cardiovascular disease risk score.

*Milligrams per deciliter of blood
**Milligrams per liter

Doctor-approved test #2: Bone density

When researchers study healthy super-agers aged 90 and older, strong bones are one of their defining features.¹⁴

That may be because, like muscles, bones are live organs that secrete substances that may be beneficial to overall health and longevity.¹⁵

For example, bones secrete osteocalcin, a hormone that plays a role in bone remodeling. When osteocalcin circulates in the body, it’s thought to play a role in everything from helping muscles to produce ATP to regulating brain neurotransmitters.

Because of these varied roles, it’s thought that, as bones wear away, osteocalcin levels drop, contributing to many age-related health problems, including diabetes, low muscle mass, and cognitive issues.^{16 17} (At least, that’s the theory. Most of this research has been done on mice.)

Osteocalcin aside, loss of bone density can, of course, lead to fractures, which can increase your risk of death for up to 10 years after a break.¹⁸

It’s especially important to keep tabs on bone health if you’re in any of these high-risk categories:

• You’re female and went through menopause before age 45.
• You’ve been sedentary most of your adult life.
• You take medications such as diuretics or stomach-acid blockers, which are linked with an increased risk of osteoporosis.
• You have a history of nicotine use or excessive alcohol consumption.
• You have a medical condition, such as diabetes or thyroid disease, that raises your risk.
• You have a family history of osteoporosis.

▶ How to measure it

Dual-energy X-ray absorptiometry (DEXA) scans are a type of X-ray that measures the amount of bone mineral content packed into a square centimeter of bone.

Insurance often won’t cover these scans for people younger than 65 unless there’s a documented risk of developing osteoporosis. Out of pocket, the average cost is about $300.

When you receive your DEXA results, you’ll see a T-score that represents how your bone density compares to the average bone density of a young adult with peak bone mass. A T-score of +1.0 to -1.0 means you have normal bone mineral density for someone your age. Anything below -1.0 means you might have osteopenia (low bone mineral density) or osteoporosis (porous bones that are prone to fracture).

Commercial bio age tests

If you have some money to burn, you can learn an awful lot about your body.

Here, you’ll find a quick run-down on some of the more high-tech tests you can get and what they can tell you.

However, before we get into the details, we want to point out a few caveats:

▶ Biological age can vary over time, and by organ. Someone may go through a period of accelerated aging—saying, during a period of intense stress—then their rate of aging may slow as they focus more on recovery. Additionally, organs can age at different rates. For example, someone with heart disease may have a relatively older heart than their kidneys. (Not all tests measure individual organ age, but it’s becoming more common.)

▶ Commercial tests won’t always accurately reflect the changes you’re making. Until more research supports the reliability of these tests, evaluate your behaviors over isolated test results. If you’re eating more fruits and veggies, exercising more consistently, managing stress, and otherwise slaying the healthy lifestyle department, don’t sweat your results. Focus on doing the things we know improve health.

▶ If a company pairs your test results with a hard sell for a proprietary and expensive supplement protocol, be wary. It’s better to share and discuss your results with a trusted health professional than take health advice from a profit-seeking stranger over the internet.

Commercial test #1: DNA methylation

DNA methylation is a biological process that chemically alters DNA. Because the rate of methylation accelerates with aging, it can be used to estimate someone’s biological age and life expectancy, finds research.^{19 20 21}

The Horvath Clock and DunedinPACE both measure specific biomarkers that can be used to better understand someone’s methylation rate. Scientists developed these tests to help other scientists study how various lifestyle factors, environmental exposures, and medicines affect aging. They didn’t develop the tests as a way for the average person to pinpoint their biological age. (Which hasn’t stopped companies from selling DNA methylation testing kits to the public.) They cost about $300.

If you decide to get one of these tests, keep in mind your results won’t give you a complete picture of your health and longevity. Aging typically occurs at varying rates throughout the body. Your liver might age faster than your heart or brain, for example. So if you measure DNA methylation in your blood, that’s all you know about. Put another way, a DNA methylation test isn’t a substitute for your annual wellness checkup or blood work.

Commercial test #2: Telomere analysis

Telomeres—the protective caps on the ends of chromosomes—wear away with age. The length of a telomere can predict how many times a specific cell can divide before dying.

Abnormally short telomeres are associated with several genetic diseases. For this reason, when physicians suspect someone might have inherited a genetic disease, they’ll order a specific type of telomere test—the flow-FISH test—to measure the telomere length in all the cells in a blood sample.^{22 23}

It’s more debatable whether telomere tests can predict aging in healthy people.

Just as importantly, the telomere test marketed to the public, known as the qPCR telomere test, isn’t used in research or medicine. These $100 tests are fine if you’re merely curious—just don’t base health and fitness decisions on your results.

Commercial test #3: VO2 Max

For years, only elite athletes cared about VO2 max, which describes the maximum amount of oxygen that your body can use during exercise.

More recently, however, some experts have suggested that VO2 max can serve as a measure for athletes and non-athletes alike to track the rate at which their bodies are aging.

People with high VO2 max tend not only to be more physically fit but also less likely to develop heart disease, diabetes, cancer, or stroke.^{24 25 26 27}

In an observational study that followed the health outcomes of 5,107 Danish men over 46 years, men with above-average V02 max during middle age lived an average of five years longer than men with below-average V02 max. Each unit increase in VO2 max was associated with a 45-day increase in longevity. The researchers suggested VO2 max may more accurately predict all-cause mortality than high cholesterol, obesity, high blood pressure, and insulin resistance.²⁸

You might think of V02 max as a canary and your aging body as a coal mine.

As you age, your chest wall becomes more rigid, the muscles that surround the lungs weaker, and the oxygen-carrying blood vessels calcified and less elastic. The heart also squeezes with less force, max heart rate drops, muscle mass and strength decline, the mitochondria in cells and muscles lose their effectiveness, among other differences.

In addition to raising your risk for many different diseases, these changes can also affect VO2 max, which tends to decline 10 percent per decade starting around age 30.^{29 30}

In the past, the only way to reliably measure VO2 max was in a fitness lab.

You would wear a metabolic mask and a heart monitor while you ran or cycled to exhaustion. The mask collected your expired carbon dioxide and monitored how much oxygen you sucked into your lungs. This lab-based testing is still the most accurate way to measure V02 max as well as other key fitness metrics such as:

• Max heart rate, or the highest number of times your heart can beat per minute during exercise
• Ventilatory threshold 1, or the point during exercise when the body switches from mainly using fat for fuel to using a combination of fat and glucose or glycogen (stored glucose) for fuel.
• Ventilatory threshold 2, or the point where your body moves away from aerobic metabolism (which uses oxygen) to anaerobic metabolism (which doesn’t use oxygen).
• Tidal volume is the amount of air inhaled or exhaled during each breath

Depending on where you live, you might be able to get your VO2 max tested for around $150.

However, if you don’t have access to a VO2 max clinic, three somewhat less accurate options exist.

▶ The 1-mile walk test

Wear a heart rate monitor as you walk one mile on a flat surface, such as a treadmill or running track. As soon as you complete the mile, record your heart rate and walk time. Then, plug it into the following formula to calculate your VO2 max:

132.853 — (0.0769 × Weight) — (0.3877 × Age) + (6.315 × Sex) — (3.2649 × Time) — (0.1565 × Heart rate)

If that feels like too much math, you can also use a free online tool.

▶ The smartwatch test

Many smartwatches will estimate your VO2 Max for you based on information the watch gathers from your workouts, sex, and age. Compared to in-office testing, smart watches can over- or underestimate V02 max, especially in people who are very out of shape or extremely fit.³¹

Because of this, you don’t necessarily want to use your smart watch measurement to determine your current state of health. However, it can help you to see trends. For example, does your VO2 estimate drop after a few weeks of skipping your usual spin class? If so, that’s good information to have.

▶ The PR test

Fitness performance correlates with longevity. If you’re getting faster at running a certain distance or can go a longer distance than before, you’re getting fitter and increasing your chances of living a long, healthy life.

One way to test this: the 12-minute run test, also known as the Cooper test. (This is a validated way to estimate VO2 max—and shows about a 90 percent correlation with lab-based measurements.)

Here’s how it works:

Run as fast as you can on a flat surface, such as a treadmill set at a 1 percent incline or running track, for 12 minutes. After 12 minutes, record your distance. Then, plug it into one of the following formulas to calculate your VO2 max.

In lieu of doing math, you can also use a free online calculator.

How to change your biological age

Try to think of the information you gather about your body as just that—information.

It’s not a moral judgment of who you are as a person.

Just as importantly, it’s not a permanent situation.

• If you’re weaker than other people your age, you can grow stronger.
• If your cholesterol or blood glucose levels are high, you can take steps to lower them.
• If your body is aging faster than your birthdays, consider exploring key lifestyle changes that may help turn the situation around.

You have options. However, most people make two big mistakes when it comes to longevity-related lifestyle changes.

Mistake #1: Ignoring evergreen, big-impact strategies

It’s the simple, boring, “I’ve heard this a million times before” health practices that, when done consistently, add up to a long, healthy life.

We’re talking about things like…

• Eating more minimally processed foods and fewer ultra-processed foods
• Consuming more brightly colored fruits and veggies
• Moving your body regularly
• Getting enough rest and sleep
• Enjoying community, time in nature, and other activities that make life meaningful
• Keeping alcohol intake moderate
• Not using tobacco
• Wearing sunscreen
• Flossing

And that’s just a partial list.

According to thousands of studies, people who practice these and other high-impact strategies not only live longer, but also live better. They’re stronger, happier, and less likely to spend their later years disabled or in pain.

(If you’d like to see where you stand when it comes to big impact health and longevity strategies, check out our FREE Longevity Assessment.)

However, when it comes to health, fitness, and longevity, many people pursue options with minimal impact (at best). They reach for the latest, trendy supplement rather than taking steps to quit smoking, as just one example.

Here’s the thing: Big rock strategies require changes in behavior. If daily physical activity were as easy as popping a pill, walkers and cyclists would clog up the streets in your neighborhood.

(It’s precisely this reason why so many people need the support of a certified health coach who has undergone training in the science of behavior change.)

Mistake #2: Not turning data into action

The data gathered from biomarker aging tests can give you a sense of control.

However…

Data, in isolation, doesn’t lead to a longer life.

Gathering data without changing your behavior is like checking your reflection in the mirror, seeing spinach wedged between your incisors, and leaving it there.

You need to remove the spinach for the mirror check to be worthwhile.

Biomarker testing is the same.

If you don’t use your bio data to inform behavior change, you’re wasting your money and time.

Consider your biomarker data as a baseline or starting point.

Then, use it to assess whether various lifestyle changes or medical interventions are moving you closer to your goal of living a longer, healthier life.

References

Click here to view the information sources referenced in this article.

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