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LAB RESULTS

What your blood work can tell us (and what it can’t)

Vitamin D, B12, iron, homocysteine and hs-CRP: what each number means, and why “in range” isn’t the whole story.

Why we ask (and why it’s optional)

A quiz tells us about your goals and habits. A blood test tells us what is actually going on inside. Together, they let us set amounts with more care. You can build a formula without labs, and you can add results later.

We read labs to shape a supplement formula. We do not diagnose anything. Your doctor is the right person to interpret your results as a whole.

The markers we look at most

• Vitamin D (25-hydroxy vitamin D): the standard way to measure your vitamin D stores. It helps us decide how much D3, if any, belongs in your blend.
• Vitamin B12: B12 helps keep nerve and blood cells healthy.* Blood levels are a starting point; a related test called MMA (methylmalonic acid) can add detail.
• Ferritin and iron: ferritin is a protein that stores iron, so it gives a picture of your iron reserves. Iron and ferritin are usually read together.
• Homocysteine: an amino acid your body recycles with the help of folate, B12 and B6. A higher number can be a sign those B vitamins aren’t keeping up.
• hs-CRP (high-sensitivity C-reactive protein): a general signal of inflammation, the body’s natural response to stress or injury. It can rise for everyday reasons, like a cold or a hard workout.

“In range” and “optimal” aren’t the same

A lab’s reference range is built from a large group of people who were tested. It shows where most results fall. It is not a target made just for you.

So a result near the bottom of the range might be technically “normal” while still suggesting room to improve, and expert groups don’t always agree on the best level. For vitamin D, for example, different organizations name different cut-offs. When we set amounts, we look at where you fall within the range, not just whether you are inside it.

Why low iron isn’t always a reason to take iron

This one surprises people. During illness or inflammation, your body can deliberately lock iron away in storage and absorb less from food. It is a protective move. In that situation, iron in the blood can look low even though your body is managing it on purpose, and ferritin can read high or normal while blood iron reads low.

Low iron can also have causes that need a doctor’s attention. That is why we don’t add iron to a formula just because one number is low. If your iron results are low, talk with your doctor first, and we’ll follow their guidance.

What labs can’t tell us

One blood draw is a snapshot. Results shift with the season, a recent illness, a hard workout, what you ate and even the lab that ran the test. Labs also can’t tell us how you feel. That is why we use them alongside your answers, not instead of them.

Retesting

Many nutrient levels change slowly. If you want to see how your formula is fitting, a retest after about three months is a reasonable checkpoint for markers like vitamin D. Upload new results anytime and we’ll review your formula against them.

Sources

1. NIH Office of Dietary Supplements: Vitamin D fact sheet
2. NIH Office of Dietary Supplements: Vitamin B12 fact sheet
3. NIH Office of Dietary Supplements: Iron fact sheet
4. NIH National Institute of Diabetes and Digestive and Kidney Diseases: Anemia of inflammation or chronic disease

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This page is general information, not medical advice. Check with your doctor or pharmacist before starting a supplement, especially if you take medication, are pregnant or nursing, or have a health condition. Updated October 1, 2026.