Calcium and Vitamin D3
Vitamin D3 is required to absorb dietary and supplemental calcium.
Calcium
The primary structural mineral of bones and teeth.
Vitamin D3
The sunshine vitamin behind bone, immune, and mood health.
Great to combine
These two are frequently stacked together; they complement each other and are commonly taken at the same time.
How to take them
Calcium
- Dose
- 500–1,000 mg per day from supplements, only to fill dietary gaps
- Timing
- Citrate any time; carbonate with food. Split doses above 500 mg.
Vitamin D3
- Dose
- 1,000–4,000 IU per day for most adults
- Timing
- With a meal containing fat for best absorption
Buying Calcium and Vitamin D3?
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Frequently asked
Can you take Calcium and Vitamin D3 together?
Yes, they are commonly taken together. Vitamin D3 is required to absorb dietary and supplemental calcium.
What's the best time to take Calcium and Vitamin D3?
Around the same time works well. Calcium: Citrate any time; carbonate with food. Split doses above 500 mg.. Vitamin D3: With a meal containing fat for best absorption.
How do Calcium and Vitamin D3 interact?
Synergy: Work better together than alone. Vitamin D3 is required to absorb dietary and supplemental calcium.
Related pairings
Boron + Calcium
Boron influences how the body retains and uses calcium, supporting bone mineralization.
Calcium + Iron
Calcium taken at the same time inhibits iron absorption; separate them by at least two hours.
Calcium + Vitamin K2
K2 activates the proteins that bind dietary calcium into the bone matrix.
Calcium + Magnesium
Compete for absorption at very high single doses; keep intake balanced rather than mega-dosing one.