NutriStack
Levothyroxine and Magnesium L-Threonate, timing-sensitive.
Magnesium L-threonate has not been studied directly with levothyroxine, but it supplies magnesium ions that may interfere with thyroid hormone absorption. This is most relevant for people with borderline thyroid control, pregnancy, thyroid cancer suppression therapy, or a history of fluctuating TSH. Separating the doses is a low-burden way to avoid preventable under-replacement.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- Levothyroxine and Magnesium L-Threonate
- Pair type
- Timing Sensitive
- Evidence (highest tier)
- Emerging
- Source citations
- 2 sources
- Stack Score effect
- −5 to your Stack Score (per scored timing-sensitive row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Timing Sensitive · Emerging evidence
Timing Sensitive
What is happening. Magnesium L-threonate has not been studied directly with levothyroxine, but it supplies magnesium ions that may interfere with thyroid hormone absorption. This is most relevant for people with borderline thyroid control, pregnancy, thyroid cancer suppression therapy, or a history of fluctuating TSH. Separating the doses is a low-burden way to avoid preventable under-replacement.
Mechanism. Divalent cations can bind levothyroxine or reduce its solubility in the gastrointestinal tract. Magnesium L-threonate is expected to carry this risk through its magnesium content even though form-specific clinical data are limited.
Recommendation. Take magnesium L-threonate at least 4 hours after levothyroxine. If you use it daily, keep the schedule stable and monitor thyroid labs after starting or stopping it.
Minimum separation. 240
Sources (2)
- Liwanpo L, Hershman JM. Conditions and drugs interfering with thyroxine absorption. Best Pract Res Clin Endocrinol Metab. 2009;23(6):781-792. PMID 19942153
- Skelin M, Lucijanic T, Amidzic Klaric D, Resic A, Bakula M, Liberati-Cizmek AM, Gharib H, Rahelic D. Factors Affecting Gastrointestinal Absorption of Levothyroxine: A Review. Clin Ther. 2017;39(2):378-403. PMID 28153426
Stack Score
How this pair moves the number.
Effect on the composite score
If both Levothyroxine and Magnesium L-Threonate are in the same stack, this pair applies −5 to your Stack Score (per scored timing-sensitive row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
Check your full routine
One pair was the worked example. NutriStack runs every pair in your stack at once.
Drop in your supplements and prescriptions and the public database surfaces every interaction, synergy, timing rule, and contraindication, every one linked to its primary source.