What Blood Tests Should You Get at 40?

The medical reality of your 40s: this is when the consequences of decades of accumulated diet, exercise, stress, and genetics start showing up as actual measurable risk. The good news is that nearly all of it is reversible at this stage if you catch it early. The bad news is that the standard annual physical workup — a CBC, basic metabolic panel, lipid panel, and maybe TSH — isn't designed to catch the things that actually matter at this age.

Specifically, the standard workup misses or under-tests for:

• Modern cardiac risk markers — ApoB is a stronger predictor of cardiovascular events than LDL cholesterol, and Lp(a) is a genetically-determined risk factor that 20% of people have elevated without knowing. Neither is in the basic lipid panel.
• Insulin resistance — fasting insulin starts rising years before A1c becomes abnormal. Catching it at this stage (when fasting insulin is creeping up but glucose is still normal) gives the widest reversible window for intervention.
• Inflammation — hs-CRP independently predicts cardiac risk, autoimmune patterns, and metabolic dysfunction. The 0.0-3.0 mg/L range matters; standard CRP is too imprecise to capture the cardiac-risk-relevant numbers.
• Subclinical thyroid dysfunction — hypothyroidism peaks in the 40-60 window, especially in women, and TSH alone misses the cases where TSH is "normal-ish" but Free T4 is in the lower range. Adding Free T4 to the workup catches these.
• Vitamin D deficiency — affecting ~70% of US adults (40% deficient + 30% insufficient). Critical for bone density (which starts declining in the 40s), immune function, mood, and possibly cardiovascular health.
• Hormonal shifts — both perimenopause in women (typically starting 38-44) and testosterone decline in men (gradual from the 30s onward) become relevant in the 40s. Standard workups don't test for either.

The point isn't that the standard workup is bad — it's a fine starting point. The point is that it's incomplete for the decade where modifiable risk becomes most measurable.

Here's the workup we'd recommend for an average healthy 40-something adult, organized by what each test contributes:

The standard baseline (from a General Wellness Panel — $89.99):

• CBC with Differential — blood cell counts, screens for anemia, infection, immune patterns
• Comprehensive Metabolic Panel (CMP) — kidney function (BUN, creatinine, eGFR), liver function (ALT, AST, alkaline phosphatase), electrolytes, fasting glucose
• Lipid Panel — Total Cholesterol, LDL, HDL, Triglycerides
• TSH — basic thyroid screen

The 40+ upgrades to add:

• Hemoglobin A1c — 90-day average blood sugar; the standard for diabetes screening. Annual check at minimum, especially with family history or weight changes.
• Fasting Insulin — rises before A1c becomes abnormal; catches insulin resistance at the most reversible stage.
• Free T4 (added to TSH) — completes the thyroid picture; catches subclinical hypothyroidism that TSH alone misses.
• Vitamin D, 25-Hydroxy — critical at this age for bone density and overall health.
• hs-CRP — high-sensitivity C-Reactive Protein; cardiac-risk-relevant inflammation marker.
• Ferritin — iron stores; women in particular often have low ferritin in their 40s that contributes to fatigue.

The Essential Health Panel ($189.99) bundles all of the above (CBC, CMP, Lipid, TSH, A1c, Fasting Insulin, Vitamin D, hs-CRP, Ferritin) in one comprehensive 40+ annual workup. That's our most-recommended starting point for someone in their 40s; it costs roughly $250-400 if ordered piecemeal through insurance.

Add these once for cardiac risk baseline (lifetime tests):

• Lp(a) Lipoprotein(a) — genetically determined; test once in your life. About 20% of people have elevated Lp(a) and don't know it; elevated Lp(a) carries 2-3x normal cardiac risk regardless of LDL.
• ApoB — the truer atherogenic particle count compared to LDL. Particularly valuable if your LDL is borderline or you have family history of cardiac disease. The Heart Health Panel ($74.99) bundles ApoB + Lp(a) + hs-CRP with a Lipid Panel — efficient if you're getting these as standalone tests rather than the Essential Health bundle.

Hormonal changes in the 40s are nearly universal but often dismissed because "you're not menopausal yet" or "you're a man, hormones don't matter." Both are wrong.

For women in their 40s:

• Perimenopause typically starts in the late 30s to mid 40s — often 8-10 years before the last period. Symptoms include cycle changes (length, flow), sleep disruption, mood changes, hot flashes, weight gain, hair thinning, brain fog, and decreased libido.
• The Women's Hormone Panel ($159.99) covers Estradiol, Progesterone, FSH, LH, Testosterone (Free & Total), SHBG, DHEA-S, and Prolactin — the complete profile for evaluating perimenopausal hormonal shifts.
• If you're still cycling, test on days 2-5 of your cycle for the cleanest baseline reading.
• See our perimenopause guide for the full workup and interpretation.

For men in their 40s:

• Testosterone declines gradually from the 30s onward, with rates varying widely between men. By the 40s, many men have measurably lower testosterone than they did at 25, with effects on energy, mood, libido, body composition, and recovery from exercise.
• The Men's Hormone Panel ($159.99) covers Total + Free Testosterone, SHBG, Estradiol, DHEA-S, Cortisol, Prolactin, and IGF-1 — the complete male hormonal picture.
• Free Testosterone matters more than Total Testosterone; SHBG (the binding protein) rises with age and reduces the bioavailable fraction even when Total looks normal.
• Morning draws (7-10 AM) are essential — testosterone peaks early and drops 30-50% by afternoon.

The simple rule: annual for everything in the core workup, biannual for the markers that are trending toward concern, lifetime-once for Lp(a).

Annual workup (every 12 months):

• Complete Blood Count (CBC)
• Comprehensive Metabolic Panel (CMP)
• Lipid Panel (or Heart Health Panel)
• TSH + Free T4 (thyroid)
• Hemoglobin A1c
• Vitamin D (twice yearly — winter and summer — if you've ever been deficient or live in a northern climate)
• hs-CRP
• Ferritin (especially for women still menstruating)

Lifetime once (genetically fixed, doesn't change):

• Lp(a) Lipoprotein(a) — test once and trust it forever
• Hemoglobin variants (only if family history of thalassemia, sickle cell, etc.)
• APOE genotype (Alzheimer's risk, only if family history)

Every 3-6 months while actively managing:

• Whatever marker you're tracking — if you started a new medication, made a major lifestyle change, or are working to correct a deficiency, retest that specific marker on the timeline appropriate to it (vitamin D at 8-12 weeks after starting supplementation, A1c at 3 months after diet change, etc.)

Establishing a longitudinal record matters more than any single result. The trend is more useful than the snapshot. A vitamin D level of 32 ng/mL is uninformative on its own, but if it was 45 last year and 38 the year before, the trajectory tells you something is happening (sun exposure changed, weight changed, gut absorption changed). Same with A1c, fasting insulin, lipid markers, and hormones. Order from the same lab (Quest, Labcorp, or BioReference) consistently so reference ranges and assay methodologies are comparable.

This is part of why DTC lab testing (where you own your data and can plot it over years) is a meaningful shift from insurance-billed testing (where results live in your provider's portal and may be hard to compile across years and providers).