Read time: 5 minutes

While routine bloodwork covers cholesterol and blood sugar, vitamin D is typically left out—meaning most people have no clue about their levels. My latest test shows why that matters.

Last week, I got my annual vitamin D test results back: 32.5 ng/mL, down from 44 ng/mL in 2023. While this falls within the standard “normal” range of 30-100 ng/mL, it’s well below my target of 50 ng/mL. Physicians whose work I follow recommend 50-70 ng/mL for optimal immune, bone health, and anti-inflammatory benefits.

This matters because vitamin D affects far more than just bone health—it’s vital for prenatal health, brain function, immunity, pregnancy, cancer prevention, cardiovascular health, and muscle function. Maintaining muscle mass becomes increasingly important as we age, making optimal vitamin D levels even more critical.

Here’s what I’ve learned: being “normal” doesn’t guarantee you’re at your healthiest level. When you dig deeper, you ask better questions: not just “Am I deficient?” but “Am I at the level that best supports my immune system, bones, muscles, and brain?” It’s not about achieving perfect numbers—it’s about knowing where you stand so you can take action.

5 Steps to Get the Vitamin D Data You Need

This approach gives you concrete data to work with instead of guessing about your status.

Step 1: Request Annual Testing

Vitamin D is not part of the standard blood panel in the U.S. During your next appointment or annual wellness visit, ask your doctor to include vitamin D (25-OH vitamin D) in your bloodwork.

Why it works: You can’t improve what you don’t measure. Annual testing helps you adjust your approach based on data.

Step 2: Set Your Personal Target

Expert recommendations based on post-pandemic research shows that levels between 40 and 70 ng/mL can provide greater protection against many adverse health outcomes. Work with your healthcare provider to determine your target based on your health goals and current status.

The standard approach: Avoid deficiency (stay above 20 ng/mL)

The optimization approach: Target the range where benefits are maximized (40-70 ng/mL)

My target: 50 ng/mL minimum.

Step 3: Set Your Supplementation Strategy

Based on your current level and target, determine appropriate dosing. Work with your healthcare provider, especially if you’re targeting levels above standard recommendations.

My plan: Increasing from 2,000 IU daily to 5,000 IU daily to reach my 50 ng/mL target.

Step 4: Choose Third-Party Tested Supplements

Not all supplements deliver what’s on the label. My primary care provider emphasized this when I mentioned my supplement plan—third-party testing ensures you’re actually getting the dosage you’re paying for.

My choices: I’ve been using Pure Encapsulations vitamin D and plan to try Thorne next. Both brands are third-party tested and well-regarded for quality.

What to look for: Third-party verification from organizations like NSF International, USP, or ConsumerLab.

Step 5: Create an Implementation Plan

The best supplement plan fails if you don’t take it consistently. Make it automatic.

My approach:

• Keep supplements visible on my kitchen counter
• Take with breakfast when I’m already in a routine
• Set a phone reminder for the first two weeks until it becomes habit

Implementation tips: Link it to an existing habit, choose the same time daily, and remove any barriers to consistency.

What to Expect

Vitamin D levels typically respond to supplementation within 2-3 months. I’ll retest at my next annual wellness visit to see if my increased dosage gets me closer to my 50 ng/mL target.

Keep in Mind

1. The science is moving faster than the guidelines – Research continues to reveal optimal ranges that may differ from standard recommendations
2. You’re in the driver’s seat – Doctors have a lot on their plates. Help your doctor by regularly requesting tests for critical biomarkers like vitamin D. I keep a running list in the Notes app on my phone
3. Be aware of essential nutrients that are difficult to get from food or the environment – These include vitamin D and vitamin B12

Your Next Step

If you haven’t had your vitamin D tested recently, add it to your next appointment. A simple blood test gives you the exact data you need to ensure you’re on track.

Thanks for reading!

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Have you had your vitamin D tested recently? What were your results? I’d love to hear about your experience in the comments.

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References & Additional Reading

Vitamin D Deficiency and Testing:

• Cleveland Clinic. (2024). Vitamin D Deficiency. https://my.clevelandclinic.org/health/diseases/15050-vitamin-d-vitamin-d-deficiency
• Mayo Clinic. (2024). Vitamin D. https://www.mayoclinic.org/drugs-supplements-vitamin-d/art-20363792
• Endocrine Society. (2011). Evaluation, treatment, and prevention of vitamin D deficiency: Clinical practice guideline. Journal of Clinical Endocrinology & Metabolism, 96(7), 1911-1930. https://academic.oup.com/jcem/article/96/7/1911/2833671
• Roth, D. E., et al. (2025). Global prevalence and disease burden of vitamin D deficiency: a roadmap for action in low- and middle-income countries. PubMed. https://pubmed.ncbi.nlm.nih.gov/39861407/
• Patrick J. McCullough, et al. (2019). Daily oral dosing of vitamin D3 using 5000 TO 50,000 international units a day in long-term hospitalized patients: Insights from a seven year experience. ScienceDirect. https://www.sciencedirect.com/science/article/abs/pii/S0960076018306228

Supplement Quality and Third-Party Testing:

• ConsumerLab.com. Supplement Testing and Reviews. https://www.consumerlab.com/

Image credit: Kaboompics.com

This post does not constitute medical advice. Please consult with your healthcare provider regarding your specific health needs.