Guide

In your 40s

The 40s are arguably the highest-leverage longevity decade. Atherosclerosis is silently progressing; metabolic risk often emerges; muscle and bone start to need active preservation. What you do now meaningfully changes 70s-and-beyond outcomes.

Top six priorities

1. Get a coronary artery calcium (CAC) score. If >0, start aggressive lipid lowering. If 0 (in non-FH adults), reassess in 5 years. This is the single most impactful test at this stage.
2. Aggressive apoB loweringif elevated. Target <90 mg/dL primary prevention, <65 if high lifetime exposure. See statins, ezetimibe.
3. Build VO₂max and grip strength: exercise with structured zone 2 + intervals + resistance. Your 40s output determines your 70s baseline.
4. Blood pressure: home cuff, target home average <125/80. See hypertension.
5. Sleep apnea screening if any snoring, witnessed apneas, or daytime sleepiness. See AHI.
6. Colon-cancer screening at 45 per current US guidelines. Earlier if family history.

What to measure annually

• Full lipid panel + apoB.
• HbA1c, fasting insulin / HOMA-IR.
• hsCRP.
• Liver enzymes and FIB-4 score.
• Thyroid screen (TSH).
• Vitamin D, B12 if at risk.
• Body composition (DEXA if accessible).
• VO2max estimate at minimum (wearable or treadmill).
• Grip strength.

Reasonable additions if motivated

• One-time APOE genotype if you want it.
• Periodic epigenetic age tracking (trend, not single values).
• Wearable HRV and sleep tracking.

For women specifically

Perimenopause may begin in the 40s. See the women’s guide and menopausal hormone therapy. Bone-density and cardiovascular trajectories shift markedly with oestrogen decline; early conversation with a clinician about hormone therapy and bone protection is valuable.