Blood Tests by Age: What to Test in Your 20s, 30s, 40s, and 50s

Quick answer

Every adult benefits from a full baseline panel and a one-time lipoprotein(a) check. Layer in extra focus as you age. Add nutrition and metabolic markers in your 20s and 30s. Add heart and hormone markers in your 40s. Add kidney, bone, and cancer screening in your 50s and beyond.

Your 20s: build the baseline

Most adults never test their blood in their 20s. A job or visa requirement is often the only reason they do. That is a missed chance. This decade is when many long-term trends get set.

What to test.

• A full blood panel: complete blood count, metabolic panel, lipid panel plus ApoB, liver, kidney, and thyroid markers.
• Vitamin D, B12, and ferritin.
• Lipoprotein(a), once in your life.
• A hormone panel, if you have symptoms or are planning a family.

How often. yearly for the full panel.

What to watch for.

• Low iron in women who have periods, even with a normal hemoglobin reading.
• Low vitamin D, very common in young adults who work indoors.
• Early signs of insulin resistance, if diabetes runs in your family.

A baseline at 25 gives you and your doctor something real to compare against for decades. Several risk markers, like lipoprotein(a), are most useful before any lifestyle-related damage builds up.

Your 30s: catch the early drift

Metabolic changes often start quietly in your 30s. Fasting insulin creeps up. Triglycerides climb. A liver marker called ALT inches higher. All of this happens before HbA1c or fasting glucose move much.

What to test.

• A full blood panel, with extra focus on HbA1c, fasting insulin, ApoB, hs-CRP, ALT, and triglycerides.
• Vitamin D, B12, and ferritin.
• A hormone panel for women planning a family.

How often. yearly for the full panel. Every 6 months for the metabolic markers if any drift shows up.

What to watch for.

• HbA1c slowly trending up over several years.
• Fasting insulin above 10.
• ALT climbing into the mid-20s to mid-30s range, an early sign of fatty liver.
• Triglycerides above 100 alongside a falling HDL.

Catching drift in your 30s buys you decades of a healthier trend. The earliest metabolic shifts are the easiest to fully reverse with diet, exercise, and weight changes.

Your 40s: heart focus and hormone shifts

Heart risk rises meaningfully in your 40s. Hormones start to shift too. This shows up most in women entering perimenopause, and in men with a slow decline in testosterone.

What to test.

• A full blood panel.
• Heart focus: ApoB, lipoprotein(a) if not already done, hs-CRP, and a lipid panel.
• Hormones for women: FSH, LH, and estradiol on day 3 of your cycle, AMH, progesterone on day 21, and a full thyroid panel.
• Hormones for men: total and free testosterone, SHBG, and estradiol. Add PSA in your late 40s.

How often. yearly for the full panel. More often for heart and hormone markers if flagged.

What to watch for.

• ApoB drifting above 90.
• HbA1c moving into the pre-diabetes range.
• eGFR starting to drift down, even while still in the normal range.
• Rising day-3 FSH in women, an early sign of perimenopause.
• Low testosterone in men, especially with fatigue or low libido.

This is the decade where lifestyle-related risk most often crosses into something worth acting on. Strong heart risk management starting now prevents events in your 50s and 60s.

Your 50s: watch more closely

Most major chronic diseases become more likely in your 50s. Your focus widens to include kidney, bone, and cancer screening alongside the usual markers.

What to test.

• A full blood panel.
• Heart focus: ApoB, hs-CRP, and possibly homocysteine, with active lipid management.
• Kidney focus: creatinine, eGFR, and a urine protein test.
• A full thyroid panel, including antibodies if not already checked.
• Hormones for women: estradiol, FSH, and AMH, to assess menopause status.
• Hormones for men: testosterone, free testosterone, and PSA.
• Cancer screening: mammograms, pap smears, colon screening, and prostate checks, as your doctor recommends.

How often. heart and metabolic markers twice a year. A full panel yearly. Cancer screenings on the schedule your doctor sets.

What to watch for.

• A continued heart risk trend. Any yellow flag deserves active management now.
• A falling eGFR is a real warning sign, if it drops more than about 5 points a year.
• A TSH between 4 and 10 with symptoms, a sign of mild thyroid underactivity.
• B12 deficiency, since absorption naturally declines with age.

Most heart attacks and strokes in this decade were predictable years ahead of time. Blood markers made that possible.

Your 60s and beyond

Everything above continues, plus:

• Closer B12 monitoring, since absorption keeps declining.
• Vitamin D, homocysteine, B12, and ferritin, all linked to brain health and frailty.
• Ongoing cancer screening, per your doctor's guidance.
• More frequent eGFR checks.
• Hormone management, where appropriate, as your doctor advises.

Our full guide to blood testing for seniors after 60 goes deeper on this stage.

What stays true at every age

• Lipoprotein(a) only needs checking once, at any adult age.
• A trend across several tests matters more than any single reading.
• Read your results against the healthy target range, not just the population average.
• Testing without follow-up action does not change your outcome. Pair it with real lifestyle steps.

A simple cadence by decade

Our guide to how often you should test goes deeper on the right frequency for you.

Whatever decade you are in, a &you Labs panel can be matched to your age and stage of life.

Frequently asked questions

Is testing in my 20s really worth it if I feel fine?

Yes. A baseline at 25 becomes your reference point. You and your doctor can compare against it for the next 40 years. A few markers, like lipoprotein(a), are most useful before any lifestyle damage builds up.

Do I need imaging too, not just blood tests?

A chest X-ray and ECG every 1 to 2 years makes sense from your 40s onward. Cancer screenings follow their own guidelines by age. Blood testing is the foundation, and imaging rounds out the picture. Our article on why blood testing anchors prevention explains why.

Should women test hormones routinely?

A baseline female hormone panel in your 30s is useful for fertility planning, even without symptoms. Routine retesting is not needed unless your cycle changes, or perimenopause symptoms show up.

Should men test testosterone routinely?

Yearly testosterone checks become worth it in your 40s. This matters most with fatigue, low libido, or stuck weight. Testing earlier without symptoms is optional.

What if a parent had diabetes or heart disease?

Start monitoring at least 10 years before the age they were diagnosed. If your father had a heart attack at 50, start close heart marker checks by your late 30s.

Key takeaways

• 20s: build your baseline, with a focus on nutrition and metabolic markers. Check lipoprotein(a) once.
• 30s: catch early drift in HbA1c, fasting insulin, ALT, and triglycerides.
• 40s: shift focus to heart markers and hormone changes, in both women and men.
• 50s: widen your focus to kidney, bone, and cancer screening.
• 60s and beyond: keep up full monitoring, with added focus on B12 and brain health markers.