Can you take selenium and vitamin D together?

Tested together, early signs.

As of August 2026, selenium and vitamin D have been tested together in 1 trial, in adults with new Graves' disease and low selenium and vitamin D, and the one trial so far came out ahead of usual care alone. Scored under the same rules as everything here.

7 studies · 1 tested the actual pair

See all 7 studies

What you’re seeing

• Selenium renders solid: for thyroid, it is well studied and it works.
• Vitamin D renders hollow: for bone, it is well studied and it does not work.
• The woven cord is the rare part: one trial gave both together, and the one trial so far came out ahead of usual care alone.

You can tell before you read a word.

Magnesium + L-theanine are sold together in the same aisle. No trial has ever tested the pair. When that is true, we draw nothing between them. The nothing is the review.

The pair trial

• 2022Randomized trial · 42 people · adults with new Graves' disease and low selenium and vitamin D · the pair helpedsource

The other 6 studies on file tested each one alone. See all 7 studies

Fair questions

Is it safe to take selenium and vitamin D together?+

The studies on this page gave both together and reported no harm from the combination. That is not the same as a safety trial, and it says nothing about your dose or your medication.

How many studies is this based on?+

1 that gave the pair together. The papers are listed above with links to the source.

Deeper

What each one is on its own+

Selenium

• Thyroidsolid
• Cancer preventionhollow
• Jointshalf-there

Vitamin D

• Bonehollow
• Blood sugarsolid
• Pregnancyhalf-there

Pairs that have been tested+

• Selenium has been tested with L-carnitine, L-arginine, probiotics, CoQ10, vitamin E, inositol.
• Vitamin D has been tested with magnesium, folate, chromium, probiotics, omega-3, iron.

These are the combinations someone has actually run a study on. Every other pairing here is air.