"I just had my blood work done. Everything looks normal."
This sentence sounds reassuring. Often though, it shouldn't be.
Not because blood tests are wrong. But because normal and healthy are often two very different things.
What "normal" actually means
Most lab reference ranges are statistical, not physiological targets. They are usually derived by:
- Sampling a large population.
- Excluding overt disease.
- Defining the middle ~95% as "normal."
That range reflects what is common, not what is protective. And in a population where metabolic dysfunction, cardiovascular disease, and low fitness are widespread, "normal" often just means: average risk.
Normal vs. optimal: a concrete example
Take insulin resistance. For many labs, HOMA-IR values up to ~3 are still considered "normal."
But from a prevention and longevity perspective, a HOMA-IR below ~1.2 has been associated with better cardiometabolic outcomes. Both values can fall within the reference range. Only one reflects good metabolic health.
Same story with cardiovascular risk.
- ApoB up to ~1.3 g/L (130 mg/dL) is often labeled normal.
- The 2019 ESC/EAS dyslipidaemia guidelines recommend ApoB < 0.8 g/L (80 mg/dL) for high-risk patients, with even lower targets for very-high-risk.
Again: normal on paper, very different biological futures.
This gap between "not alarming" and "actually protective" is where most false confidence comes from.
Why this matters for prevention
Chronic diseases don't start at the cutoff. They start with:
- Compensation.
- Subtle drift.
- Slow accumulation of risk.
For years, sometimes decades, values remain technically normal while underlying processes are already moving in the wrong direction. By the time something becomes "abnormal," the system has often been under strain for a long time.
The markers that deserve more attention
This is about focusing on signals that matter over time. A few examples:
- Lp(a): not modifiable, but critical for lifetime cardiovascular risk stratification.
- ApoB: particle burden, not just cholesterol concentration.
- HOMA-IR: early metabolic stress, long before diabetes.
- VO₂max: one of the strongest predictors of all-cause mortality (Mandsager et al., JAMA Network Open 2018).
- Resting heart rate (RHR): a window into autonomic balance and cardiovascular efficiency.
For all of these, the goal isn't just to stay "within range." The goal is to:
- Be in a low-risk zone.
- Monitor direction.
- Intervene early when trends shift.
Trajectories beat snapshots
One isolated blood test tells you very little. What actually matters:
- Is ApoB slowly creeping up year over year?
- Is insulin staying low or rising to compensate?
- Is VO₂max improving, stable, or quietly declining?
- Is resting heart rate drifting upward despite similar lifestyle?
A slow negative trend inside the reference range is far more concerning than a single slightly elevated value caught early.
Health is dynamic. Diagnostics should be too.
The core reframe
Blood tests are not a pass–fail exam. They are navigation tools.
If your goal is long-term health and function, the real questions are:
- Where am I relative to optimal, not average?
- How is this changing over time?
- Am I accumulating resilience or risk?
"Everything looks normal" often just means: nothing is bad yet. Prevention starts earlier than that.
If you've ever been told everything is fine while something didn't feel quite right, you're not alone. Hit reply if you want me to break down how often markers should actually be tracked — and which ones are worth repeating versus ignoring.
See you soon,
Niko