Magnesium and Vitamin D
Each entry’s own grades, side by side. A grade says how strong the evidence is for one outcome — it does not rank one entry over the other.
Compound or practice
Magnesium
A cofactor in 300+ reactions that a large fraction of adults under-consume — real, modest benefits for sleep, blood pressure, and migraine.
Grade B4 graded outcomesrevised Jul 10, 2026
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
Compound or practice
Vitamin D
A steroid hormone precursor that most temperate-latitude adults run low on — worth correcting, oversold as a cure-all.
Grade A5 graded outcomesrevised Jul 10, 2026
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
Graded in both
Outcomes are matched by name. Two entries can describe the same outcome in different words, so one listed further down may still be graded in the other.
No outcome has the same name in both entries. They may still overlap under different wording — read the two lists below.
Graded only in Magnesium
- Correcting low status Moderate effectEvidence grade A
- Blood pressure Small effectEvidence grade B
- Migraine prophylaxis Moderate effectEvidence grade B
- Subjective sleep Small effectEvidence grade B
Graded only in Vitamin D
- Correcting deficiency (25(OH)D) Large effectEvidence grade A
- Fracture / fall risk (deficient elderly + calcium) Moderate effectEvidence grade B
- Respiratory infection risk Small effectEvidence grade C
- Cancer / CVD prevention (replete adults) Trivial effectEvidence grade D
- Type 2 diabetes prevention Trivial effectEvidence grade D
Conditions
Only in Magnesium
- Migraine May improveEvidence grade B
- Hypertension May improveEvidence grade B
- Insomnia May improveEvidence grade C
Only in Vitamin D
- Osteoporosis / bone loss May improveEvidence grade B
- Seasonal low mood May improveEvidence grade C
- Autoimmune disease No clear effectEvidence grade C
What each entry says about the other
- Magnesium’s entry · Works together: Required cofactor for activating vitamin D.
- Magnesium’s entry · Goes with: Required cofactor for activating vitamin D.
- Vitamin D’s entry · Works together: Magnesium is a required cofactor for activating vitamin D; low magnesium blunts the response.
- Vitamin D’s entry · Goes with: Magnesium is a required cofactor for activating vitamin D; low magnesium blunts the response.
Both columns are read from the entries as they stand in this library. A comparison is not advice to take either one, and it is no substitute for a clinician who knows the person.