Your annual check-up probably measures cholesterol, blood sugar and blood pressure, calls them "normal," and sends you home. But some of the numbers that best predict how you'll actually age either aren't on the standard panel — or are printed and never explained. The good news: most of them respond to small, repeatable habits. Here are five worth knowing, and one thing you can do for each.
1. ApoB — the real "cholesterol number"
LDL Low-Density Lipoprotein (LDL) cholesterol measures the amount of cholesterol your particles carry. ApoB Apolipoprotein B (ApoB) counts the number of particles — and it's the particles, not the cholesterol inside them, that lodge in artery walls. A 2019 review in JAMA Cardiology notes cholesterol can only enter the arterial wall inside an apoB particle, so apoB "more accurately measures the atherogenic risk" than LDL cholesterol does. Two people with identical LDL can carry very different particle counts — and very different risk.
The habit: the moves that lower LDL lower apoB too — cutting saturated fat, eating more soluble fibre (oats, beans, fruit), and staying active. Ask your doctor to add apoB to your next lipid panel.
2. Fasting insulin — the early-warning light
Blood sugar Blood Glucose (Fasting) can look fine for years while the body quietly overworks to keep it there. In the Whitehall II study of 6,538 adults, insulin sensitivity dropped steeply in the five years before a diabetes diagnosis, while fasting glucose only surged in the final ~3 years. Fasting insulin flags that struggle long before glucose or HbA1c Glycated Hemoglobin (HbA1c) move.
The habit: a short walk after meals. A 2022 meta-analysis found light-intensity walking significantly lowered both post-meal glucose and insulin versus sitting. Even 2–5 minutes counts.
3. hs-CRP — hidden inflammation
High-sensitivity C-reactive protein hs-CRP (High-Sensitivity C-Reactive Protein) measures low-grade inflammation you can't feel. Pooling 160,309 people without heart disease, the Emerging Risk Factors Collaboration found CRP tracked continuously with future coronary heart disease, stroke and death. It's a cheap window onto a process that accelerates aging.
The habit: build muscle. Around 30–60 minutes of muscle-strengthening a week was associated with 10–17% lower all-cause mortality, cardiovascular disease and diabetes — and regular activity is one of the most reliable ways to bring inflammation down.
4. HbA1c — your 3-month sugar average
HbA1c Glycated Hemoglobin (HbA1c) estimates average blood sugar over ~3 months, so it's harder to game than a single fasting reading. It matters even without diabetes: in non-diabetic adults, HbA1c was more strongly linked to cardiovascular disease and death than fasting glucose was. Watching it drift upward — even within "normal" — is a signal.
The habit: the same post-meal walk, plus a simple plate order — vegetables and protein before the rice or noodles blunts the glucose spike that feeds HbA1c over time.
5. Resting heart rate — the number your watch already knows
A lower resting heart rate Resting HR generally reflects a stronger, more efficient heart. In a dose-response meta-analysis, every 10 beats-per-minute higher resting heart rate was associated with about 17% higher all-cause mortality and 15% higher cardiovascular risk. No lab needed — your phone or watch tracks it.
The habit: regular aerobic activity gradually lowers resting heart rate by improving fitness — and fitness itself is powerfully protective. Among 122,007 adults, the least-fit had roughly five times the mortality risk of the fittest, with no observed upper limit to the benefit.
Two bonus tests that need no lab
Want more signal for free? Grip strength predicts mortality strikingly well — in the 139,691-person PURE study, each 5 kg lower grip meant 16% higher all-cause mortality, a stronger predictor than blood pressure. And your walking speed walking-speed is a rough proxy for the cardiorespiratory fitness above.
The takeaway
No single number defines your health, and "normal" isn't the same as "optimal." Tracked together — and nudged by walking after meals, lifting twice a week, and moving your heart rate regularly — these markers turn a once-a-year check-up into something you can steer. This article is general wellness information, not medical advice; discuss your results and any changes with a qualified clinician, as reference ranges vary by lab, age and population.
Curious about your own metabolic picture? Explore the nubu microbiome test →
In the nubu app, each metric below shows your own latest value and its healthy range.
References
- Sniderman AD, et al. Apolipoprotein B Particles and Cardiovascular Disease — JAMA Cardiol (2019)
- Tabák AG, et al. Trajectories before type 2 diabetes (Whitehall II) — Lancet (2009)
- Kaptoge S, et al. C-reactive protein and vascular risk — Lancet (2010)
- Selvin E, et al. Glycated hemoglobin and cardiovascular risk — NEJM (2010)
- Aune D, et al. Resting heart rate and mortality — Nutr Metab Cardiovasc Dis (2017)
- Buffey AJ, et al. Walking breaks and cardiometabolic markers — Sports Med (2022)
- Momma H, et al. Muscle-strengthening and mortality — Br J Sports Med (2022)
- Leong DP, et al. Grip strength and mortality (PURE) — Lancet (2015)
- Mandsager K, et al. Cardiorespiratory fitness and mortality — JAMA Netw Open (2018)
