Top 5 Lab Tests Every Woman Should Consider in Her 40s

By Candise Yang, L.Ac., NCCAOM | Serving Oakland, Berkeley, Rockridge, and the East Bay

Entering your 40s can feel like hitting a strange in-between zone - your cycles might still come regularly, but something feels different. You’re more tired. You wake up sweating at 3 a.m. You forget words mid-sentence. Maybe your mood swings feel bigger than they used to, or your digestion is suddenly more sensitive. These are common signs that your body is moving through perimenopause.

And while these changes are natural, they’re also not something you need to “just deal with.” Getting key lab work can give you insight into what’s happening beneath the surface - and help you feel more grounded and empowered in your care.

Below are five foundational lab tests I recommend for most women in their 40s, especially if you’re experiencing any of the symptoms above.

1. Thyroid Panel (TSH, Free T3, Free T4, and TPO Antibodies)

Thyroid shifts are common in perimenopause—and often misdiagnosed or missed altogether. A full thyroid panel (not just TSH) helps rule out both hypothyroidism and autoimmune thyroid conditions (like Hashimoto’s).

Common signs:

  • Fatigue

  • Weight gain or difficulty losing weight

  • Cold hands and feet

  • Depression

  • Hair thinning

  • Brain fog

Why it matters: The thyroid interacts with estrogen, progesterone, and cortisol. Suboptimal thyroid function can amplify perimenopausal symptoms - and correcting it can dramatically improve quality of life.

2. Vitamin D (25-Hydroxy Vitamin D)

This isn’t just about bones. Vitamin D acts more like a hormone and plays a key role in immune health, mood, blood sugar regulation, and even hormone balance.

Common signs of deficiency:

  • Low energy

  • Recurrent colds

  • Mood dips or seasonal depression

  • Bone or joint aches

Why it matters: Low Vitamin D can worsen PMS, hot flashes, and mood swings. Many of us - especially those with darker skin tones or minimal sun exposure - are chronically low and don’t know it.

3. Fasting Insulin & Glucose (or a Hemoglobin A1C)

Blood sugar stability becomes harder to maintain in our 40s - especially with fluctuating estrogen. Even if your diet hasn’t changed, you may notice more sugar cravings, stubborn weight gain, or energy crashes.

Why it matters:

  • Elevated insulin (even with normal glucose) can signal early insulin resistance - a common issue in perimenopause that often goes undetected.

  • Catching this early allows for gentle interventions with food, herbs, and acupuncture - before a prediabetes diagnosis ever enters the picture.

4. Ferritin (Iron Storage)

You don’t need to be anemic to be iron-depleted. Many women, especially those with heavy or long menstrual cycles, have low ferritin - leading to fatigue, shortness of breath, or poor recovery from exercise. It’s not uncommon for serum (circulating) iron levels to be sufficient and for there also to be a concurrent low level of ferritin. 

Why it matters:

  • Low ferritin can contribute to fatigue, hair thinning, poor sleep, and worsened anxiety.

  • Over-supplementing iron when it’s not needed, however, can cause harm - so testing first is key.

5. Hormone Panel (Estradiol, Progesterone, +/- DHEA/Testosterone)

Hormone panels can be tricky in perimenopause due to fluctuating levels. But they’re still worth testing at the right time in your cycle.

Why it matters:

  • Low progesterone is one of the first signs of perimenopause and contributes to insomnia, anxiety, and shorter cycles.

  • High or erratic estrogen may cause heavy periods, breast tenderness, or irritability.

  • Understanding these levels helps us target treatment more precisely - whether that’s with acupuncture, herbs, or integrative referrals.

How We Use Lab Work in a Holistic Setting

In my practice, we take the whole picture into account. Your labs are just one part of the story. We also listen deeply to your experience, assess your constitution through pulse and tongue diagnosis, and offer gentle interventions - from acupuncture and herbal medicine to lifestyle shifts that match your unique needs.

If you already have recent labs, we’re happy to review them with you. If you’re not sure what to ask your doctor for, we can help you build a respectful, collaborative request - or guide you through ordering labs yourself.

Next Steps

Feeling tired, foggy, or just… not yourself?

You don’t have to guess or go it alone.
Let’s explore what’s happening beneath the surface - and build a care plan together.