Magnesium and Vitamin D3
Magnesium is required to convert vitamin D into its active form, so low magnesium blunts D3's benefits.
Magnesium
A master mineral involved in 300+ enzyme reactions.
Vitamin D3
The sunshine vitamin behind bone, immune, and mood health.
Designed to work as a pair
One is required for the other to do its job, so they belong together in a stack.
How to take them
Magnesium
- Dose
- 200–400 mg elemental magnesium per day
- Timing
- Evening for sleep support; with food to reduce GI upset
Vitamin D3
- Dose
- 1,000–4,000 IU per day for most adults
- Timing
- With a meal containing fat for best absorption
Buying Magnesium and Vitamin D3?
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Frequently asked
Can you take Magnesium and Vitamin D3 together?
Yes, they are commonly taken together. Magnesium is required to convert vitamin D into its active form, so low magnesium blunts D3's benefits.
What's the best time to take Magnesium and Vitamin D3?
Around the same time works well. Magnesium: Evening for sleep support; with food to reduce GI upset. Vitamin D3: With a meal containing fat for best absorption.
How do Magnesium and Vitamin D3 interact?
Cofactor: Required for the other to do its job. Magnesium is required to convert vitamin D into its active form, so low magnesium blunts D3's benefits.
Related pairings
Glycine + Magnesium
A sleep pairing with a built-in shortcut: magnesium glycinate is magnesium bound to glycine, so that form already delivers both. A standalone 3 g dose before bed (the amount sleep studies used) tops up the glycine, lowering core body temperature while magnesium relaxes muscles and calms the nervous system.
L-Arginine + Magnesium
Magnesium supports vascular smooth muscle relaxation alongside nitric oxide from arginine.
Ashwagandha + Magnesium
Commonly combined for stress relief and better sleep quality.
Boron + Magnesium
Boron reduces urinary magnesium loss and supports magnesium status, complementing magnesium supplementation.