5 Labs Every Woman Over 35 Should Ask For

By R. Murray

I have sat across from countless women in clinic who came in with the same frustrating story: fatigue that won't lift, hair that's thinning, weight that's shifted despite no obvious changes, a brain fog that makes them feel like they're operating at 70 percent. Their previous labs came back "normal." Their doctor told them everything looked fine.

Everything did not look fine. They just weren't running the right labs.

Standard annual bloodwork is a blunt instrument. It catches major pathology. It is not designed to catch the subclinical drift that happens in your 30s and 40s.... the slow erosion of optimal function that accumulates quietly before it shows up as a diagnosable condition. If you're a woman over 35 and you want a more complete picture of your health, here are five tests worth asking about.

1. Ferritin

Ferritin is the storage form of iron, and it is almost never included in routine bloodwork unless you specifically ask or unless your hemoglobin is already flagged as low. That's backward. You can have normal hemoglobin and critically low ferritin.... meaning your body's iron stores are depleted well before anemia is visible on a standard CBC.

Low ferritin is one of the most underdiagnosed causes of fatigue, hair loss, and reduced exercise tolerance in women. The "normal" range on most lab reports bottoms out around 12 ng/mL. But the research on symptomatic ferritin deficiency suggests that levels below 30.... and especially below 50.... are associated with the symptoms I described above. Many integrative and functional medicine physicians aim for a ferritin between 70 and 100 for optimal energy and hair health.

Ask your doctor: "Can we add a ferritin to my routine labs?" It is inexpensive and straightforward.

2. Vitamin D (25-Hydroxyvitamin D)

Vitamin D deficiency is extraordinarily common, particularly in northern latitudes, among people who work indoors, and among women of color whose melanin reduces cutaneous synthesis. Despite this, it remains off most standard panels.

The reference range on lab reports marks deficiency below 20 ng/mL. But optimal function.... particularly for immune health, mood, bone density, and cardiovascular risk.... is generally associated with levels between 40 and 60 ng/mL. Many physicians don't act until you hit clinical deficiency. By the time you're there, you've been running suboptimally for a long time.

I wrote about my own experience getting my Vitamin D levels corrected in this post. If you're supplementing, the D3 form is better absorbed than D2, ideally taken with a fatty meal. A well-reviewed D3/K2 combination is available on Amazon if you need one.

3. Full Thyroid Panel (Not Just TSH)

Most physicians order only a TSH (thyroid-stimulating hormone) to screen for thyroid disease. TSH alone misses a meaningful subset of thyroid dysfunction, particularly in the subclinical or autoimmune range.

A more complete thyroid assessment includes:

- TSH (still a useful starting point)

- Free T4 (the inactive form of thyroid hormone)

- Free T3 (the active form; low T3 with normal TSH is common and symptomatic)

- TPO antibodies (to screen for Hashimoto's thyroiditis, an autoimmune condition that can smolder for years before TSH shifts)

Women over 35 have a significantly higher risk of autoimmune thyroid disease than men of the same age. Hashimoto's in particular is often associated with fatigue, weight changes, hair thinning, constipation, and mood changes.... all of which can easily be attributed to stress or lifestyle if the right labs aren't run.

If your TSH has ever come back "borderline high" or if you have a family history of thyroid disease, push for the full panel.

4. Fasting Insulin

Fasting glucose tells you how high your blood sugar is right now. Fasting insulin tells you how hard your pancreas is working to keep it there. The difference matters enormously.

Insulin resistance.... the state where your cells no longer respond efficiently to insulin, so your pancreas has to produce more and more to maintain normal glucose levels.... can be present for a decade before glucose levels shift and type 2 diabetes appears on a lab report. During that decade, insulin resistance is actively contributing to weight gain (particularly abdominal), fatigue, brain fog, increased cardiovascular risk, and hormonal disruption including worsening PCOS in women who are predisposed.

Fasting insulin is not on standard panels. Ask for it. Optimal fasting insulin is generally below 8 mIU/L. Many labs flag it as normal up to 20 or 25, which reflects population averages in a metabolically unwell population.... not optimal health.

5. High-Sensitivity CRP (hs-CRP)

Chronic low-grade inflammation is a root mechanism in cardiovascular disease, metabolic syndrome, autoimmune conditions, and a growing list of chronic illnesses. High-sensitivity CRP (hs-CRP) is the most accessible blood marker for systemic inflammation and is inexpensive to run.

Standard CRP is used to detect acute infection or major inflammation. The high-sensitivity version captures chronic, low-level inflammation that standard CRP misses entirely. Values above 1.0 mg/L indicate elevated cardiovascular risk; values above 3.0 mg/L are considered high risk. Many women who eat reasonably well and don't smoke walk around with hs-CRP values in the 2 to 5 range and have no idea.

Elevated hs-CRP can be addressed: anti-inflammatory nutrition, sleep optimization, reducing visceral fat, and treating underlying conditions all lower it. You can only address it if you know it's there.

How to Ask for These Labs

Be direct with your physician. You can say: "I'd like to add ferritin, 25-hydroxy Vitamin D, free T3, free T4, TPO antibodies, fasting insulin, and hs-CRP to my routine labs. Can we do that?" Most physicians will order them without hesitation. Some may push back on cost or clinical justification; if so, it's reasonable to ask which ones concern them most and go from there.

If your doctor's office won't run them and you want access to your own data, services like LabCorp and Quest allow direct lab ordering in many states.

You deserve more than a normal that doesn't feel normal. These tests are a starting point. And if you want to pair good labs with good sleep, that combination does more for long-term health than most interventions I know of.... I covered the sleep piece here.

Stay Connected

Enjoy these posts? Get new articles from R. Murray delivered to your inbox. Or reach out via the contact page!

Subscribe to My Medical Journal

This post reflects my personal experience and is for informational purposes only. It is not medical advice. Please consult your own physician before making any health decisions.