Longevity
Your annual physical was designed to catch disease. It is good at that. What it was never designed to do is measure trajectory — how well you are ageing, and in which direction you are heading — and most of the measures that track that never appear on the…
Your annual physical was designed to catch disease. It is good at that. What it was never designed to do is measure trajectory — how well you are ageing, and in which direction you are heading — and most of the measures that track that never appear on the form.
None of what follows replaces a physical. It sits alongside it, and the point is to bring better questions to an appointment rather than to self-diagnose from a printout.
This is the one that surprises people, and it is worth being precise about what it does and does not show.
The PURE study, published in The Lancet, followed roughly 140,000 people across 17 countries. Over a median of four years, each 5 kg reduction in grip strength was associated with a 16% higher risk of death from any cause (hazard ratio 1.16, 95% CI 1.13–1.20). It was also associated with cardiovascular mortality, myocardial infarction and stroke — and in that dataset it predicted all-cause and cardiovascular mortality more strongly than systolic blood pressure did.
Now the part that matters more than the headline.
PURE is a prospective cohort study. It observed people; it did not assign them to anything. That means it establishes an association, and association is not causation. Grip strength almost certainly is not doing the work itself — it is a cheap, reliable proxy for something larger: total muscle mass, neuromuscular function, nutritional status, and the accumulated burden of chronic disease.
So squeezing a hand dynamometer more often will not extend your life. Nobody has shown that training grip in isolation changes mortality. What the finding supports is narrower and still useful: grip strength is an unusually efficient window into whole-body condition, it takes thirty seconds to measure, and almost nobody measures it.
If it is low, the question it should prompt is why — not how do I train my forearms.
Cardiorespiratory fitness is the other measure with a large evidence base and almost no presence in routine care.
A Cleveland Clinic analysis of 122,007 adults who underwent treadmill exercise testing found a steep gradient: the lowest-fitness group had an adjusted hazard ratio for all-cause mortality of roughly 5.0 compared with the elite-fitness group. The relationship held across age, sex and comorbidity, and the authors found no observed upper limit at which more fitness stopped being associated with benefit.
The same caveat applies, and it is not merely academic. This is observational. People who are already unwell tend to test poorly, which drags the association in a direction that has nothing to do with training. But unlike grip strength, VO2 max is directly trainable, and the evidence that structured aerobic work raises it is separate and solid. We have written about how it is actually built.
A standard panel gives weight. Weight is the least informative number in the room.
Two people at identical weight and BMI can differ enormously in what they are carrying — muscle versus fat, and where the fat sits. Visceral fat, the fat around the organs, behaves metabolically differently from subcutaneous fat, and BMI cannot distinguish between them at all.
What is worth knowing: lean mass, fat mass, and a marker of central adiposity. Waist circumference measured properly costs nothing and outperforms BMI for metabolic risk. DEXA gives more, if you have access to it.
Muscle mass belongs on this list for the reason the grip-strength data hints at, and which we cover in muscle as an organ of longevity.
They are the most heavily marketed item in this category and the least ready.
Epigenetic clocks estimate biological age from DNA methylation patterns, and as population-level research instruments they have produced genuinely interesting findings.
As a personal test, the honest assessment is that they are not there. A recent critical review put it plainly: the performance characteristics of these clocks — sensitivity, specificity, predictive validity, reliability — sit well below the standard required of any biomarker used to guide a decision about an individual. They were built on population correlations, which is a different statistical object from individual diagnostic accuracy. Add inter-platform variability between array versions, poor reproducibility between laboratories, tissue-specific differences, and training cohorts skewed towards European populations.
Our position: interesting science, not yet a personal test. If you buy one, treat the number as entertainment rather than information, and do not make a health decision on the strength of it.
Some of the most useful numbers are already being drawn and simply passed over as "normal". Fasting glucose and insulin, a fuller lipid panel, and inflammatory markers all carry more signal than a single in-range flag suggests — particularly read as a trend across years rather than a snapshot. We covered those separately.
A single reading tells you where you are. A decade of readings tells you where you are going, which is the question the annual physical was never built to answer.
Do not order everything. The instinct to chase every new test is the failure mode of this entire field, and most of these measures change slowly enough that annual is plenty.
The useful move is narrower: ask for the ones that are cheap, repeatable and actionable — grip strength, waist circumference, a fitness estimate, and the blood markers you are already having drawn — and then track the direction over years.
And take the results to a clinician who can interpret them in the context of your history. Bringing a better question to that conversation is the entire point.
Ready when you are
Read the library first. When you want to act, start with a conversation with a licensed provider, entirely by telehealth.