6 Numbers Your Doctor Checks That Actually Predict How Long You'll Live
Your annual physical hides a handful of data points that longevity researchers consider among the most powerful predictors of lifespan — here's what each one means and what to do about it.
Most people leave a doctor’s appointment with a stack of lab results they don’t fully understand and a vague sense that everything is either “fine” or “a little high.” The doctor scans the numbers, flags the obvious problems, and moves on. What rarely happens is a deeper conversation about which of those numbers genuinely predicts how long you’ll live, and which are mostly noise.
The answer, it turns out, is that a small subset of measurable values has an outsized relationship with lifespan. A landmark 35-year follow-up of more than 44,000 participants in the Swedish AMORIS cohort found that the people who made it to 100 had consistently more favorable biomarker profiles from middle age onward, particularly in markers of metabolism, inflammation, and organ function. These weren’t people with extraordinary genetics doing extraordinary things. They were people whose bodies, as measured by blood and basic physical tests, ran cleaner for longer. Here are the six numbers worth actually paying attention to.
VO2 max: the fitness number that predicts survival better than almost anything else
VO2 max is the maximum volume of oxygen your body can use during intense exercise. It’s a measure of how efficiently your heart, lungs, and muscles work together. And it may be the single most powerful mortality predictor available without surgery or expensive imaging. 🫀
Research cited by DexaFit and published in major cardiology journals shows that people in the bottom quartile of VO2 max for their age have a risk of death roughly five times higher over the following decade than those in the top quartile. That number is larger than the mortality effect of smoking in several studies. Larger than hypertension. Larger than obesity. Five times. And yet most annual physicals don’t measure it.
What makes VO2 max particularly interesting for longevity purposes is that it’s trainable at any age. Dr. Vassily Eliopoulos, a Cornell-trained physician and co-founder of Longevity Health, includes it among his core biomarkers for a reason: it reflects the health of virtually every major system simultaneously. When VO2 max declines, so does cardiovascular resilience, metabolic efficiency, and cognitive reserve.
How to actually get your number:
Ask your doctor for a CPET (cardiopulmonary exercise test), which is the gold standard
Many fitness facilities and sports labs offer treadmill or cycling protocols that estimate VO2 max directly
Consumer devices like Garmin and Apple Watch generate estimates from heart rate data during exercise, which are imprecise but give you a directional read
Aim for above 40 mL/kg/min if you’re a man under 50; above 35 mL/kg/min if you’re a woman — though the goal is simply to improve your own number, whatever it is
The good news: each 1 MET increase in cardiorespiratory fitness reduces all-cause mortality risk by around 13 to 15%. You don’t need to become an athlete. You just need to move enough, consistently enough, that your aerobic system gets progressively stronger. 🏃 That said, think carefully: when did you last do something that genuinely pushed your breathing?
HbA1c: your three-month blood sugar report card
HbA1c (glycated hemoglobin) measures the percentage of hemoglobin in your blood that’s coated with sugar, reflecting your average blood glucose over the past two to three months. Your doctor checks it routinely, but the ranges they use to flag “normal” versus “pre-diabetic” are not the same as the ranges associated with maximum longevity. 🔬
The standard clinical cutoff for concern is an HbA1c above 5.7% (pre-diabetic territory). But centenarian studies paint a more precise picture. Research consistently shows that people who live past 100 maintain HbA1c levels below 5.5% throughout their lives, with the most favorable longevity outcomes clustered around 4.8 to 5.2%. An HbA1c of 5.6% — technically in the “normal” range — may still represent metabolic drift that accumulates consequences over decades.
Why does this matter so much? Chronically elevated blood sugar damages:
Blood vessel walls, accelerating arterial aging and cardiovascular risk
Kidney filtration units, quietly eroding function over years
Nerve fibers, contributing to neuropathy and cognitive decline
Mitochondria, the organelles responsible for cellular energy production
The relationship between blood sugar control and aging is not subtle. Insulin resistance, which often precedes elevated HbA1c by years, is now understood to drive inflammation that accelerates nearly every age-related disease. The Swedish AMORIS study found that lower glucose at older ages was directly associated with greater odds of reaching 100. Getting your HbA1c below 5.4% is probably one of the highest-leverage metabolic interventions available to most people. ⚡
The routes to better HbA1c are well-established: reduce refined carbohydrates, increase fiber intake, build lean muscle mass, prioritize sleep (poor sleep reliably worsens insulin sensitivity), and walk after meals. None of this is exotic. LongevityHub’s beginner biohacks guide covers several of these habits with supporting research worth reading alongside this piece.
ApoB: the cholesterol number your doctor might not be ordering
Most standard lipid panels measure LDL cholesterol, the number most people know as “bad cholesterol.” The problem is that LDL measures the amount of cholesterol carried in a particular type of particle, not the number of particles themselves. ApoB (apolipoprotein B) counts the particles directly, and that distinction turns out to matter considerably. 💊
Dr. Eliopoulos calls ApoB the most important blood marker for long-term heart health. A 2025 systematic review of 15 studies covering more than 593,000 participants confirmed that ApoB outperforms LDL cholesterol and non-HDL cholesterol for predicting cardiovascular events. The reason is straightforward: each ApoB-containing particle that enters an artery wall contributes to plaque formation. Two people can have identical LDL readings while one has twice as many particles. The person with more particles has meaningfully more cardiovascular risk, and LDL alone won’t reveal that difference.
The longevity-relevant targets:
Below 90 mg/dL for general prevention
Below 80 mg/dL for those with existing cardiovascular risk factors
Below 65 mg/dL if you have a history of heart disease
Most standard blood panels don’t include ApoB. You usually have to request it specifically. This is worth doing. Centenarian studies consistently show that people who make it to 100 maintain low ApoB-containing particle burdens throughout their lives, which researchers believe prevents the slow, progressive arterial damage that kills most people in their 70s and 80s. 🧬
The AMORIS cohort data adds nuance here: high ApoB relative to ApoA-I (the protective HDL-associated protein) was associated with higher cardiovascular mortality regardless of the age at which the measurement was taken. This means midlife ApoB levels carry real information about what happens decades later.
High-sensitivity CRP: the inflammation signal hiding in plain sight
High-sensitivity C-reactive protein (hs-CRP) measures low-grade inflammation circulating in your blood. It’s not the same as CRP measured during an acute infection or injury, which can spike to dramatic levels. Hs-CRP catches the quiet, chronic, low-level inflammation that doesn’t cause obvious symptoms but accelerates biological aging at the cellular level. 🔬
The numbers that matter:
Below 1.0 mg/L is the longevity-associated target, and centenarians typically land here
1.0 to 3.0 mg/L indicates elevated risk that most clinicians consider moderate
Above 3.0 mg/L significantly increases cardiovascular disease, cancer, and dementia risk, according to research reviewed by Optimal Health’s 2025 longevity guide
The Japanese cohort study cited in the Swedish AMORIS follow-up specifically found that low inflammation, measured through markers including CRP, was a key predictor of exceptional survival. That’s consistent with what we understand about how aging works biologically: chronic inflammation damages DNA, disrupts cellular repair processes, accelerates telomere shortening, and drives the dysfunction of nearly every organ system over time. 💡
What drives hs-CRP up?
Excess body fat, particularly visceral fat around the organs
Poor sleep, which disrupts inflammatory regulation within two to three nights
Processed food, particularly refined seed oils and added sugars
Sedentary behavior, independently of weight
Periodontal disease — your gum health genuinely affects systemic inflammation in ways that surprise most people
I think hs-CRP is underused precisely because it’s not attached to a dramatic diagnosis. A CRP of 2.8 mg/L won’t get a red flag on your lab printout. But over 20 years, it represents a biological environment that ages tissues faster and reduces the odds of a long, healthy life. Ask for hs-CRP by name at your next physical.
Blood pressure: the quiet killer that’s also the most fixable
Blood pressure is so widely checked that most people treat it as routine background noise. That’s a mistake. Sustained high blood pressure is one of the most reliably documented accelerators of biological aging, and it operates silently, damaging arterial walls, the heart, kidneys, and brain without producing symptoms until the damage is substantial. ❤️
The numbers that matter for longevity purposes are more aggressive than the traditional clinical thresholds:
Optimal is below 120/80 mmHg, consistently
130 to 139 systolic represents early damage accumulation that significantly increases long-term risk
Each 10 mmHg increase in systolic blood pressure above 115 is associated with roughly a doubling of cardiovascular mortality risk, according to data from the Global Burden of Disease study
Where it gets interesting from a longevity perspective is the relationship between blood pressure and brain health. The National Institute on Aging documents a strong link between midlife hypertension and late-life dementia risk, particularly when hypertension goes uncontrolled between ages 45 and 65. This means high blood pressure in your 40s may be shaping your cognitive health in your 80s, decades before any memory symptoms appear. 🧠
The modifiable levers are substantial. Unlike genetics, blood pressure responds directly to:
Sodium reduction (most people eat two to three times the optimal amount)
Regular aerobic exercise, which reduces systolic blood pressure by roughly 5 to 8 mmHg on average
Body weight, where even a 5 kg reduction can move blood pressure meaningfully
Sleep quality, since poor sleep activates stress hormones that constrict blood vessels overnight
Blood pressure is the biomarker on this list where lifestyle changes produce the fastest, most measurable results. Most people who make consistent changes see movement within four to eight weeks.
Grip strength: the deceptively simple proxy for how well your body is aging
Last on the list, and the one that raises the most eyebrows when mentioned. Grip strength sounds like a measure of how firmly you shake hands. What it actually reflects is overall musculoskeletal integrity, neurological function, lean mass adequacy, and cardiovascular health simultaneously, and it predicts all-cause mortality, cognitive decline, and cardiovascular events independently of every other marker on this list. 💪
The research behind grip strength as a longevity marker is substantial and consistent. Healthy ranges typically sit around 32 to 43 kg for men and 20 to 28 kg for women, measured with a hand dynamometer. Studies show that people with low grip strength for their age group have meaningfully higher rates of:
All-cause mortality across multiple decades of follow-up
Cardiovascular events, including heart attack and stroke
Cognitive decline and dementia
Disability and frailty in later life
The 2025 study by Ojulari and colleagues found strong associations between grip strength and insulin sensitivity in non-diabetic adults, suggesting that the grip strength signal reaches into metabolic health as well. Grip strength is essentially a window into how much functional reserve your body has built up across a lifetime of physical use. 🔬
You can test yourself now. Healthy adults under 60 should generally be able to hang from a pull-up bar for at least 60 seconds, which is a reasonable proxy test without a dynamometer. If that number surprises you, resistance training is the intervention, and it works at any age. LongevityHub’s roundup of affordable longevity tools specifically mentions grip dynamometers as one of the most cost-effective ways to track this metric regularly at home. ⚡
These six numbers sit at the intersection of what science currently understands about how bodies age well and what your doctor already has the tools to measure. You don’t need a longevity clinic or a six-figure health optimization protocol. You need to know what your VO2 max, HbA1c, ApoB, hs-CRP, blood pressure, and grip strength actually are, and then understand what direction to push each one.
One practical next step: at your next appointment, bring a list and ask specifically for ApoB and hs-CRP to be added to your standard panel. Most doctors will order them without hesitation if you ask. Those two numbers alone, in combination with your standard bloodwork, will give you a considerably more complete picture of where your biology actually stands.
Which of these six numbers do you already know — and which have you never had tested?