Is my Magnesium normal?
Free blood test checker · Standard + longevity-optimal ranges
What is a normal Magnesium level?
Magnesium is a critical mineral involved in over 300 enzymatic reactions: energy production, muscle/nerve function, blood sugar regulation, and blood pressure control. Up to 50% of Americans may be magnesium-insufficient. Serum magnesium only reflects 1% of body stores, so you can be deficient with a "normal" blood level.
| Range | Values |
|---|---|
| Standard Reference | 1.7–2.2 mg/dL |
| High Risk | > 2.5 mg/dL |
| Low Risk | < 1.5 mg/dL |
What causes abnormal Magnesium levels?
Low magnesium is caused by inadequate dietary intake (processed food diets lack magnesium), alcohol use, diuretics, PPIs (long-term use), diabetes (urinary magnesium wasting), GI diseases (Crohn's, celiac), chronic stress, and excessive sweating. Soil depletion has reduced magnesium in modern crops. High magnesium is rare and usually caused by kidney failure or excess supplementation.
When should you see a doctor?
See your doctor if magnesium is below 1.7 mg/dL, if you have persistent muscle cramps, tremors, or heart palpitations, or if you take medications that deplete magnesium (diuretics, PPIs). If supplementing above 400 mg/day, check kidney function. RBC magnesium is a better test than serum but less commonly available.
Magnesium and longevity
Magnesium is involved in over 300 enzymatic reactions — more than any other mineral — yet up to 50% of Americans are insufficiently supplied. Its role in longevity spans cardiovascular health (regulates blood pressure and heart rhythm), metabolic function (critical cofactor for insulin signaling), bone density (works with calcium and vitamin D), sleep quality (activates the parasympathetic nervous system), and DNA repair. Serum magnesium is a poor test — it reflects only 1% of total body stores, meaning you can be significantly depleted with a "normal" blood level. RBC magnesium is more accurate but rarely ordered. Soil depletion, processed food diets, and chronic stress have created a widespread subclinical deficiency epidemic. Magnesium glycinate, threonate, and taurate have superior bioavailability compared to oxide.
Where to get a Magnesium test
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Related biomarkers
These biomarkers are often tested alongside Magnesium for a more complete picture.
Frequently asked questions
What is a normal magnesium level?
What are symptoms of low magnesium?
What type of magnesium supplement is best?
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Sources: Reference ranges based on AHA/ACC, ADA, and AACE clinical guidelines. Biological variation data from Ricos/Westgard database. Longevity-optimal ranges reflect targets used by preventive and functional medicine practitioners.
Last reviewed: April 2026. This tool provides general health information and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare provider about your specific results.