What magnesium L-threonate is
L-threonic acid is a small sugar acid. Two molecules of it bind one magnesium atom, which makes magnesium L-threonate. Because the threonate part is heavy, the compound is only about 7-8% magnesium by weight. Our labels confirm it: one product lists 2000 mg of Magtein giving 144 mg of magnesium, another 1.34 g giving 96 mg.
| Magnesium L-threonate in the daily dose | Elemental magnesium on the label | % of NRV (375 mg) |
|---|---|---|
| 1.34 g (2 capsules) | 96 mg | 26% |
| 2.0 g (3 capsules) | 144 mg | 38% |
For comparison, the same 2 g of magnesium citrate would give roughly 240-320 mg of magnesium. If your aim is simply a large amount of magnesium per capsule, L-threonate is the least efficient form in the range. People who buy it usually want this specific compound.
Reading the label
A threonate label shows two lines: the weight of Magtein or magnesium L-threonate, and below it the magnesium it contains. Only the second line counts toward the NRV. Check the number of capsules per daily dose as well, since that sets how long a 90-capsule pack lasts. We show the price per day so you can compare it with other forms.
L-threonate compared with other forms
| Form | Magnesium share by weight (approx.) | Magnesium in 1 g of the compound (approx.) |
|---|---|---|
| Bisglycinate | about 14% | about 140 mg |
| Citrate | about 11-16% | about 110-160 mg |
| Malate | about 12-16% | about 120-160 mg |
| L-threonate | about 7-8% | about 70-80 mg |
| Taurate | about 9% | about 90 mg |
The figures are calculated from the chemical formulas, and the label figure always wins. Each form has its own page, and the Magnesium page compares them all.
How to choose magnesium L-threonate: dose and number of capsules
The products here use Magtein, so the choice is mostly about dose. One product gives 96 mg of magnesium in 2 capsules, another 144 mg in 3 capsules. Decide how much magnesium you want from this compound and how many capsules a day you are happy to take. If you want a larger total amount of magnesium, you can add a citrate or bisglycinate and count both labels together. Finally, compare the price per day, shown on every product card.
What a magnesium supplement label must show
Directive 2002/46/EC requires every food supplement label in the EU to state the recommended daily dose, a warning not to exceed it, a statement that supplements should not replace a varied diet, and a reminder to store the product out of reach of young children. The label must also give the amount of magnesium per daily dose and its share of the reference value. Those are the lines we use to compare the products in this collection.
EU health claims for magnesium
Regulation (EU) No 432/2012 permits these statements for products that provide at least 15% of the NRV per daily dose:
- Magnesium contributes to normal psychological function.
- Magnesium contributes to normal functioning of the nervous system.
These claims cover magnesium in general. The EU has not authorised any claim specific to L-threonate.
Questions
Is threonate better than glycinate?
Under EU rules the claims apply to magnesium regardless of form. Glycinate gives about twice as much magnesium per gram, threonate is a different compound. Compare the magnesium per day and the price per day.
Can I combine it with another magnesium?
Add up the elemental magnesium from every product you take and follow the label directions of each.
How many magnesium L-threonate capsules should I take a day?
Take the number of capsules stated on the label, two or three depending on the product, and do not exceed the daily dose. Those doses give 96 mg or 144 mg of magnesium, which is 26% or 38% of the NRV.
When should I take magnesium L-threonate?
No official guidance names a time of day. Many labels suggest taking it with a meal. When the daily dose is two or three capsules, you can spread them over the day unless the label says otherwise.
How long does a pack last?
Divide the capsule count by the capsules per daily dose. A 90-capsule pack lasts 45 days at 2 capsules a day and 30 days at 3. We use that figure for the price per day on each product card.
Can I take magnesium L-threonate with medicines?
Ask your pharmacist if you take any medicine regularly. The NIH notes that magnesium binds some antibiotics in the gut, so those should be taken at least 2 hours before or 4-6 hours after a magnesium supplement.
Sources
- Regulation (EU) No 1169/2011, Annex XIII (reference intakes)
- Regulation (EU) No 432/2012 (permitted health claims)
- NIH Office of Dietary Supplements: Magnesium fact sheet
- Directive 2002/46/EC on food supplements
- EFSA: Health claims
Content reviewed by Inese Kalniņa, dietitian.
2026-09-02