Bryan Johnson Spends Millions to ‘Age Backwards.’ You Can Measure Your Real Biological Age for FREE (Here’s How)

You’ve probably seen the headlines, or perhaps even the documentary: Billionaire Bryan Johnson, on a relentless quest to “hack” his body and achieve the lowest possible biological age. He’s reportedly investing millions annually in an arsenal of anti-aging treatments—everything from daily supplements and weekly acid peels to hyperbaric oxygen therapy and, most controversially, plasma infusions from his teenage son.

His goal? To prove he’s not just slowing down aging, but reversing it. He claims these rigorous efforts have shaved years off his biological age, effectively making him younger than his chronological years. While some, like a recent New York Times exposé, question these claims, Johnson’s pursuit has undeniably ignited a global conversation.

Suddenly, “bio age testing” is everywhere. It’s a hot topic on popular health podcasts, and a quick Google search reveals a deluge of mail-order kits promising to reveal your biological age, pace of aging, and even your projected lifespan. With prices dropping, it’s natural to wonder: Should you jump on this trend? Are these tests worth your hard-earned money?

What if we told you that the most impactful insights into your body’s true age aren’t hidden behind a paywall or a billionaire’s extreme regimen? What if the secrets to understanding and even influencing your biological age were simpler, more accessible, and in many cases, absolutely free?

In this deep dive, we’ll strip away the hype and reveal:

• The surprisingly accurate, free methods you can use right now to gauge your overall health and pace of aging.
• The doctor-approved biomarker tests you might already be doing, and what they truly reveal.
• A critical look at commercial bio age tests: what the research says, and whether they live up to their promises.
• The two biggest mistakes people make when chasing health and longevity—and how to avoid them.

Unmasking Your Real Age: Chronological vs. Biological

Before diving into tests, let’s clarify a fundamental distinction: your chronological age versus your biological age.

Your chronological age is simple: it’s the number of years you’ve been alive, the candles on your last birthday cake. It’s a fixed, undeniable number.

Your biological age (bio age), however, is a dynamic reflection of how your cells and organs are actually functioning. Think of it as the “wear and tear” age of your body. It’s a much more accurate predictor of your health, vitality, and even longevity than your birth certificate.

Imagine two 50-year-old men. Chang lives a sedentary life in a highly polluted city, eats processed foods, and smokes regularly. Jabari, on the other hand, exercises consistently, eats a plant-rich diet, manages his stress, and enjoys time outdoors. Genetics aside, whose body do you think is biologically younger? Most would wager on Jabari, and science would likely agree. His lifestyle choices are actively influencing his cellular health.

The Science of Aging: What Bio Age Tests Actually Measure

So, how do these tests claim to peek inside your body and determine its true age? They do this by analyzing specific biological markers, or biomarkers, that are known to change with age.

Some of the most popular biomarkers include:

• Telomeres: These are the protective caps at the ends of your chromosomes, much like the plastic tips on shoelaces. Each time a cell divides, telomeres get a little shorter. Shorter telomeres are generally associated with cellular aging and an increased risk of age-related diseases.
• DNA Methylation: This is a sophisticated physiological process where chemical groups are added to your DNA, influencing gene expression without changing the underlying genetic code. The patterns of these methylation marks change predictably with age, acting like a “biological clock” for your cells.

Once a company measures these markers from a sample (blood, urine, or saliva), they plug the data into complex algorithms to estimate your biological age. However, it’s important to remember that if you visit your doctor regularly, you’re likely already tracking several biomarkers of aging. Things like blood pressure, cholesterol levels, and blood glucose can effectively predict your risk of future cardiovascular disease, a leading cause of premature death.

Your Wallet-Friendly Health Check: 5 FREE Biomarker Tests

Forget the millions spent by billionaires. You don’t need a high-tech lab or a hefty bank account to gain profound insights into your biological age. Before the advent of expensive blood-based tests, researchers relied on these simple, scientifically validated methods to assess aging. And guess what? They’re still incredibly effective.

Get Off the Floor: The Sitting-Rising Test

The link between physical fitness, strength, and longevity is undeniable. Stronger, fitter individuals tend to live longer, healthier lives. Why? Because muscles aren’t just for movement; they’re endocrine organs that secrete anti-inflammatory substances, help regulate blood sugar, slow cellular aging, and protect arteries. This cumulative effect significantly reduces the risk of age-related diseases like type 2 diabetes, high blood pressure, and heart disease. Strasser B, et al. Aging Dis. 2018.

Your ability to balance is equally critical. Research shows that 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. Araujo CG, et al. Br J Sports Med. 2022.

The Sitting-Rising Test (SRT) elegantly combines both strength and balance. Low scores on this test have been linked to a higher risk of death from cardiovascular disease in a 12-year study of over 4,000 adults. Araújo CGS, et al. Eur J Prev Cardiol. 2025.

▶ How to Measure It:

Find some clear floor space. Lower yourself to the floor into a crisscross-legged position. Then, without changing your leg position, stand back up. As you rise, observe if you need to use any part of your body—a hand, knee, or shin—for leverage.

• Scoring: Start with 10 points. For each body part you use to assist in standing, deduct one point. Deduct half a point if you lose your balance or become unsteady.

Squeeze a Ball: Assessing Grip Strength

Like the SRT, your grip strength offers a surprising window into your overall fitness. Weak hand muscles often indicate weakness throughout the rest of your body. Moreover, poor grip strength can be a strong predictor of *future* muscle weakness and disability. One study found that individuals with a weak grip were more likely to experience slow walking speed, difficulty rising from a chair, and struggles with rigorous housework 25 years later. Dodds RM, et al. Exp Gerontol. 2018.

Low grip strength has been associated with a laundry list of health concerns, including low bone mineral density, increased fall risk, poor nutritional status, depression, poor sleep, cognitive decline, and a heightened risk of heart disease, cancer, and premature mortality. Bohannon RW. Clin Interv Aging. 2019. In fact, one study even suggested that grip strength was a better indicator of longevity than blood pressure! Leong DP, et al. Lancet. 2015.

▶ How to Measure It:

Grab a standard tennis ball (or similar squeezable object). Squeeze it as hard as you can, and hold that maximal squeeze for as long as possible. Time yourself until your grip fatigues.

• Interpretation:
  • 15-30 seconds: You’re doing fine.
  • Over 90 seconds: Well above average, putting you in the upper third percentile.
  • Below 15 seconds: This indicates an area for improvement in overall strength.

Balance Act: Standing on One Foot

Your ability to balance on one foot for an extended period is crucial for reducing your risk of falls—a leading cause of injury-related death among older adults. But it’s more than just fall prevention; balancing requires the coordinated effort of multiple bodily systems: your eyes, inner ear, skeletal muscles, and brain. This intricate interplay makes it a powerful diagnostic tool. Rezaei A, et al. PLoS One. 2024.

Conditions like diabetes, heart disease, and cancer can all subtly impair balance. Thus, an inability to stand on one foot can serve as an early warning sign of eroding health and fitness.

▶ How to Measure It:

Stand near a wall or a sturdy chair for safety, if needed. Keep your eyes open and your hands on your hips. Lift your dominant leg and start timing. Stop the clock when you put your foot down. Repeat the test with your non-dominant leg. Compare your times to these averages from a Duke University study: Hall KS, et al. J Gerontol A Biol Sci Med Sci. 2017.

Your Internal Alarm: How You Feel (Fatigability)

We all get tired. A late night, a stressful week, an intense workout—these are normal causes of temporary weariness. But that’s different from fatigue, which is a persistent, worsening exhaustion that interferes with daily life, leaving you feeling mentally dull and emotionally drained.

Think of unexplained fatigue as your body’s early warning system. If you’ve ruled out the usual suspects—like too much caffeine or alcohol, dehydration, chronic stress, or extreme exercise—then fatigue could be signaling an emerging health problem such as anemia, obesity, depression, cancer, or diabetes. Glynn NW, et al. J Gerontol A Biol Sci Med Sci. 2022.

For those 60 and older, fatiguability—how worn out you feel after an activity—is a surprisingly strong predictor of longevity. Research from the University of Pittsburgh Medical Center shows a higher fatiguability score correlates with an increased risk of future death and declines in walking ability and other fitness measures. Simonsick EM, et al. J Am Geriatr Soc. 2018.

▶ How to Measure It:

Use the Pittsburgh Fatigability Scale. Rate how fatigued you *think* you would feel after completing various activities, using a scale of 0 (no fatigue) to 5 (extreme fatigue).

• Interpretation:
  • Less than 15: Excellent.
  • 15-24: A warning sign.
  • 25 and above: Regarded as severe; discuss this with your healthcare professional. Vercelli S, et al. BMC Geriatr. 2024.

Beyond the Scale: Body Composition

Your weight on the scale tells you very little about your health or biological age. What truly matters is your body composition—the ratio of fat to muscle in your body. Both too little and too much body fat, as well as too little muscle, can negatively impact your health.

Here’s a snapshot of the risks:

The gold standard methods for estimating body composition (DEXA, Bod Pod, underwater weighing) aren’t free. However, recent research suggests that a good old-fashioned tape measure can provide a comparably accurate estimate! Combest TM, et al. Mil Med. 2024.

▶ How to Measure It:

Using a flexible tape measure:

• Measure the widest part of your neck.
• Measure the narrowest part of your waist (which might be at or slightly above your navel).
• Measure the widest part of your hips (for women).

Ensure the tape is snug but not compressing the skin. Once you have these measurements, you can plug them (along with your age, sex, height, and weight) into a reliable online body fat calculator to get an estimate of your body fat percentage.

Doctor-Approved Biomarker Tests: Covered by Your Insurance?

While the previous tests are free, these next ones often require a visit to your doctor. The good news? As part of routine preventative care, your health insurance may cover them, making them essentially “free” to you.

Your Annual Blood Panel: A Window into Internal Health

There’s a reason your primary care physician recommends yearly blood work: it’s an invaluable tool. By monitoring key blood markers, you can identify trends towards conditions like type 2 diabetes or heart disease—both major contributors to premature mortality.

Many blood markers can also be influenced relatively quickly (within 6 to 12 weeks) through lifestyle changes, targeted supplements, or medication. This makes them practical for tracking whether your health modifications are working.

▶ How to Measure It:

Discuss these annual tests with your healthcare professional. They will interpret your results in the context of your overall health and may use them to calculate your cardiovascular disease risk score.

*Milligrams per deciliter of blood
**Milligrams per liter

Building Longevity: Bone Density

When researchers study “super-agers”—healthy individuals living into their 90s and beyond—one defining feature is often strong, healthy bones. This might be because bones, much like muscles, are dynamic organs that secrete substances beneficial to overall health and longevity. Dayer SR, et al. Geriatr Orthop Surg Rehabil. 2021.

For instance, bones release a hormone called osteocalcin, which plays a role in bone remodeling. When osteocalcin circulates, it’s thought to influence everything from muscle energy production to brain neurotransmitters. As bone density declines, osteocalcin levels may drop, potentially contributing to age-related problems like diabetes, low muscle mass, and cognitive issues. Mera P, et al. Mol Metab. 2016. Weivoda MM, et al. Nat Commun. 2020.

Beyond this fascinating hormonal role, loss of bone density directly increases your risk of fractures, which can increase your risk of death for up to 10 years after the break. Tran T, et al. J Clin Endocrinol Metab. 2018.

It’s particularly important to monitor bone health if you fall into any of these high-risk categories:

• Female and went through menopause before age 45.
• Sedentary most of your adult life.
• Taking medications (e.g., diuretics, stomach-acid blockers) linked to increased osteoporosis risk.
• History of nicotine use or excessive alcohol consumption.
• Medical conditions like diabetes or thyroid disease that elevate risk.
• Family history of osteoporosis.

▶ How to Measure It:

Dual-energy X-ray absorptiometry (DEXA) scans are X-rays that measure bone mineral content. Insurance typically covers these for individuals over 65 or those with documented risk factors. Out-of-pocket, they average around $300.

Your DEXA results will include a T-score, comparing your bone density to a healthy young adult’s peak bone mass:

• +1.0 to -1.0: Normal bone mineral density.
• Below -1.0: May indicate osteopenia (low bone mineral density) or osteoporosis (porous, fracture-prone bones).

The Cutting Edge (and Costly): Commercial Bio Age Tests

If you have disposable income, the commercial bio age testing market offers a deep dive into your body’s intricacies. Here’s what you need to know about some of the more high-tech options, along with crucial caveats.

But first, a few words of caution:

• Biological age is dynamic and organ-specific. Your body’s aging rate can fluctuate (e.g., during periods of intense stress vs. recovery). Also, different organs can age at different rates—your heart might be biologically older than your kidneys. Not all tests capture this nuance.
• Commercial tests may not perfectly reflect lifestyle changes. Until more robust research supports their reliability, prioritize evaluating your behaviors over isolated test results. If you’re consistently eating well, exercising, managing stress, and sleeping soundly, don’t let a single test result derail your confidence. Focus on proven health strategies.
• Be wary of hard sells. If a testing company immediately pushes a proprietary, expensive supplement regimen based on your results, exercise extreme caution. Your results are best discussed with a trusted healthcare professional, not a profit-seeking stranger online.

The DNA Methylation Clock

As we discussed, DNA methylation chemically alters DNA, and its rate accelerates with aging. This makes it a powerful tool for estimating biological age and even life expectancy. Chen BH, et al. Aging (Albany NY). 2016. Lu AT, et al. Aging (Albany NY). 2019.

Tests like the Horvath Clock and DunedinPACE analyze specific methylation patterns. These were initially developed for scientists to study how lifestyle, environment, and medicines affect aging, not for the general public to pinpoint their biological age. Despite this, companies now sell these kits directly to consumers for around $300.

Telomere Analysis: The Chromosome’s Stopwatch

Telomeres, those protective caps on your chromosomes, shorten with age, indicating how many more times a cell can divide before it dies. Abnormally short telomeres are associated with certain genetic diseases, and physicians use specialized tests like the flow-FISH test to measure telomere length in blood samples when such conditions are suspected. Alder JK, et al. Proc Natl Acad Sci U S A. 2018.

However, the predictive power of telomere tests for *aging in healthy people* is far more debatable. The qPCR telomere test, often marketed to the public for about $100, is not a standard tool in research or medicine. While it might satisfy curiosity, don’t base significant health and fitness decisions solely on these results. Vaiserman A, Krasnienkov D. Front Genet. 2020.

VO2 Max: The Ultimate Fitness Indicator

Historically, VO2 max—the maximum amount of oxygen your body can use during exercise—was the domain of elite athletes. But increasingly, experts recognize its value as a powerful measure of aging for everyone. People with a high VO2 max are not only more physically fit but also less likely to develop heart disease, diabetes, cancer, or stroke. Imboden MT, et al. J Am Coll Cardiol. 2018. Cai L, et al. Nat Commun. 2023.

One observational study, following over 5,000 Danish men for 46 years, found that those with above-average VO2 max in middle age lived an average of five years longer. Each unit increase in VO2 max was linked to a 45-day increase in longevity, suggesting it may predict all-cause mortality more accurately than traditional risk factors like high cholesterol or blood pressure. Clausen JSR, et al. J Am Coll Cardiol. 2018.

Think of your VO2 max as the canary in the coal mine for your aging body. As you age, your lung capacity decreases, heart function changes, and muscle mass declines, all impacting your body’s oxygen utilization. VO2 max typically declines by about 10% per decade after age 30. Kim C-H, et al. PLoS One. 2016.

▶ How to Measure It:

The most accurate method is a lab-based test, where you’ll run or cycle to exhaustion while wearing a metabolic mask and heart monitor. This typically costs around $150 and provides detailed metrics like max heart rate and ventilatory thresholds.

If a lab test isn’t feasible, here are some alternatives:

1. The 1-Mile Walk Test: Walk one mile on a flat surface as quickly as possible while wearing a heart rate monitor. Record your heart rate and time, then use an online calculator like Omni Calculator’s VO2 Max tool to estimate your score.
2. Smartwatch Estimate: Many smartwatches provide a VO2 max estimate based on your workouts, sex, and age. While they can over or underestimate, especially for very unfit or extremely fit individuals, they are excellent for tracking *trends*. Has your VO2 estimate dropped since you skipped your spin class? That’s valuable information.
3. The 12-Minute Run Test (Cooper Test): This validated test shows about a 90% correlation with lab measurements. Run as far as you can on a flat surface (treadmill at 1% incline or track) for 12 minutes. Record your distance and use an online calculator to find your VO2 max.

Beyond the Numbers: How to Truly Change Your Biological Age

The information you gather from any of these tests is just that—information. It’s not a moral judgment, nor is it a permanent state. If your bio age markers suggest your body is aging faster than your chronological years, remember: you have options. You can get stronger, lower your cholesterol, or improve your bone density. You can take steps to turn the situation around.

However, most people make two critical mistakes when pursuing longevity and health transformations.

Mistake #1: Ignoring Evergreen, Big-Impact Strategies

The real secret to a long, healthy life isn’t a trendy supplement or a billionaire’s extreme protocol. It’s the “boring,” “I’ve heard this a million times” health practices that, when done consistently, accumulate into profound results. We’re talking about foundational habits:

• Prioritizing minimally processed foods over ultra-processed options.
• Consuming a rainbow of brightly colored fruits and vegetables.
• Engaging in regular physical activity.
• Getting sufficient, high-quality sleep and rest.
• Cultivating meaningful relationships, spending time in nature, and pursuing activities that bring joy.
• Moderating alcohol intake and avoiding tobacco.
• Wearing sunscreen and practicing good hygiene (yes, flossing!).

Thousands of studies confirm that those who consistently practice these high-impact strategies not only live longer but also live *better*. They enjoy more strength, happiness, and a reduced likelihood of spending their later years in pain or disability. Strasser B, et al. Aging Dis. 2018.

The trap? Many people chase minimal-impact “hacks” while neglecting these fundamental behaviors. They’ll buy the latest trendy supplement before taking steps to address chronic stress or improve their diet. Why? Because big rock strategies require consistent behavioral change, which is often harder than popping a pill. This is precisely why so many individuals benefit from the support of a certified health coach skilled in the science of behavior change.

Mistake #2: Not Turning Data Into Action

Biomarker testing can provide a sense of control and clarity. You get a number, a score, a snapshot. But here’s the crucial point:

Data, in isolation, does not lead to a longer, healthier life.

Gathering data without changing your behavior is like checking your reflection in the mirror, seeing spinach stuck in your teeth, and then just walking away. The mirror check was pointless if you don’t remove the spinach!

Biomarker testing is the same. If you don’t use your bio data to inform and motivate actionable behavior change, you’re essentially wasting your money and time.

Consider your biomarker data as a baseline. Then, use it as a tool to assess whether your lifestyle changes or medical interventions are genuinely moving you closer to your goal of living a longer, healthier, and more vibrant life. The power lies not in the number itself, but in what you *do* with it.

Conclusion: Your Age, Your Power

The allure of “aging backwards” is powerful, and the world of bio age testing offers fascinating glimpses into our bodies. But as we’ve explored, the true power to influence your biological age doesn’t lie solely in expensive tests or celebrity-backed regimens.

It resides in accessible, scientifically-backed actions you can take every single day. The free and doctor-approved biomarker tests offer invaluable insights, often revealing more about your true health trajectory than many costly commercial alternatives. These simple assessments empower you to understand your body better and motivate meaningful change.

So, instead of chasing the latest anti-aging trend, embrace the wisdom of foundational health. Nourish your body with whole foods, move regularly, prioritize sleep, manage stress, and connect with your community. These aren’t just “good habits”—they are the most potent tools you possess for influencing your biological age and building a vibrant, long life.

Key Takeaways:

• Your biological age is a more meaningful health indicator than your chronological age.
• You can assess key biomarkers of aging for free using simple tests like the Sitting-Rising Test, grip strength, one-foot stand, fatigability scale, and tape measure for body composition.
• Doctor-approved blood panels and bone density scans offer crucial internal health insights, often covered by insurance.
• Commercial bio age tests like DNA methylation and telomere analysis have limitations; use them with caution and always consult a healthcare professional.
• The biggest mistakes people make are ignoring fundamental healthy lifestyle strategies and failing to translate data into actionable behavior change.
• Focus on consistent, evidence-based lifestyle choices to genuinely influence your biological age and enhance your healthspan.

Frequently Asked Questions About Biological Age

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Medical Disclaimer: This article is for informational purposes only and is not intended as medical advice. The information provided has been reviewed by licensed Registered Dietitians but should not replace consultation with a qualified healthcare provider. Individual nutritional needs vary based on age, health status, medications, and other factors. Always consult with your doctor or a registered dietitian before making significant changes to your diet, especially if you have existing health conditions or are taking medications.

Content Review: This article has been reviewed by licensed Registered Dietitians for accuracy and adherence to current nutritional science and evidence-based guidelines.