Label arithmetic · NIH DSLD snapshot 2026-08-10
How much magnesium is in magnesium l-threonate? 8.3% by weight, so 100 mg of magnesium takes 1,212 mg of l-threonate
8.3% of magnesium l-threonate is magnesium: 100 mg takes 1,212 mg of salt, 1.7 size 00 capsules. No ranked US price (Nov 2).
Magnesium L-threonate is 8.3% elemental magnesium, so 100 mg of magnesium needs 1,212 mg of compound, about 1.7 size 00 capsules at 0.8 g/mL powder density. 0 of 6 capsule labels naming L-threonate alone exceed size 000. A single ranked offer is $1.1572 per 100 mg of declared elemental magnesium (prices observed 2026-10-26 to 2026-11-02); one offer gives no median.
computed from chemical formula
Chart data
| Displayed chart text |
|---|
| oxide |
| 60.3% |
| hydroxide |
| 41.7% |
| carbonate |
| 24.8–28.8% |
| chloride |
| 12.0–25.5% |
| sulfate |
| 9.9–20.2% |
| citrate |
| 11.3–16.2% |
| aspartate |
| 7.5–15.6% |
| malate |
| 12.6–15.5% |
| glycinate |
| 11.8–14.1% |
| glycerophosphate |
| 12.5% |
| lactate |
| 10.2–12.0% |
| taurate |
| 8.9% |
| L-threonate |
| 8.3% |
| orotate |
| 7.3% |
| gluconate |
| 5.9% |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-11-02 · chemistry 2026-10-17
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Enter your container price, declared elemental amount and servings to calculate a price per 100 mg for this bottle.
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How much elemental magnesium is actually in 100, 200 or 400 mg of L-threonate?
Magnesium L-threonate is 8.3% elemental magnesium by mass (Mg(C₄H₇O₅)₂, molar mass 294.5). Magnesium L-threonate has a molar mass of 294.5 against magnesium's 24.305, so 8.3% of its mass is magnesium. Every 100 mg of elemental magnesium from it needs 1,212 mg of the compound, calculated 2026-10-17.
computedThis defined salt has one calculated elemental fraction from its formula.
Chart data
| Displayed chart text |
|---|
| L-threonate |
| 4,848 |
| oxide |
| 663 |
| Elemental magnesium | L-threonate required | Size 00 capsules that much powder fills |
|---|---|---|
| 100 mg | 1,212 mg | 2 size 00 capsules (1.7 capsules' worth of powder) |
| 200 mg | 2,424 mg | 4 size 00 capsules (3.3 capsules' worth of powder) |
| 400 mg | 4,848 mg | 7 size 00 capsules (6.6 capsules' worth of powder) |
Source · Chemical formula and atomic masses · Calculated 2026-08-10; powder density 0.8 g/mL, the top of the usual 0.6–0.8 range · release 2026-08-10-f441aa9f · CSV · method
Estimated salt mass versus assumed capsule capacity
0 of 6 capsule labels naming L-threonate alone are above the assumed size 000 capacity at powder density 0.8 g/mL, against 8 of 137 capsule labels across the audited registry. 6 fit size 0 or 00 and 0 need size 000. This is computed with a stated assumption of powder density 0.8 g/mL, the top of the usual 0.6–0.8 range and the most favorable mass per capsule.
computed with assumption6 capsule labels naming L-threonate alone can be checked against capsule sizes.
Chart data
| Displayed chart text |
|---|
| L-threonate |
| fits 6 of 6 |
| needs 000 0 of 6 |
| exceeds 0 of 6 |
| all audited |
| fits 82 of 137 |
| needs 000 47 of 137 |
| exceeds 8 of 137 |
| Mass budget verdict | Labels |
|---|---|
| Fits size 0 or 00 | 6 of 6 |
| Needs size 000 | 0 of 6 |
| Exceeds size 000 | 0 of 6 |
A size 00 capsule holds about 730 mg of powder at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range; a size 000 about 1,100 mg.
Source · NIH DSLD labels; mass balance · Recognized salt only; 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Is a label called L-threonate really L-threonate, or mixed with another salt?
0 of 8 labels naming L-threonate also name another form as of 2026-08-10. The table counts partner names on filed labels; a named blend does not establish the elemental contribution of each salt. Naming one salt is not the same as fitting it: 0 of 6 capsule labels naming L-threonate alone exceed size 000. Open the full label list to inspect individual records.
measuredA defined molecular formula permits a calculated fraction.
| Other named form | Labels |
|---|---|
| No other named form | 8 labels reviewed |
Source · NIH DSLD magnesium rows · Labels naming this salt; 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
I need 200 mg of actual magnesium. What changes in compound weight and capsules between L-threonate and other forms?
For 200 mg of elemental magnesium, L-threonate needs 2,424 mg of compound, against oxide at 332 mg. Size 00 holds about 730 mg at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range. Each row uses the stated elemental fraction; hydration ambiguity stays a range, and any price comparison remains within a single salt.
computed with assumption| Salt | Elemental fraction | Compound for 200 mg | Size 00 capsules |
|---|---|---|---|
| Magnesium L-threonate | 8.3% | 2,424 mg | 4 size 00 |
| Magnesium glycinate | 11.8–14.1% | 1,418–1,691 mg | 2–3 size 00 |
| Magnesium citrate | 11.3–16.2% | 1,238–1,770 mg | 2–3 size 00 |
| Magnesium oxide | 60.3% | 332 mg | 1 size 00 |
| Magnesium malate | 12.6–15.5% | 1,287–1,584 mg | 2–3 size 00 |
Source · Chemical formulas and capsule capacity · Calculated 2026-08-10; powder density 0.8 g/mL, the top of the usual 0.6–0.8 range · release 2026-08-10-f441aa9f · CSV · method
What does L-threonate cost per 100 mg of elemental magnesium, and which label is cheapest by declared elemental magnesium?
A single ranked offer is $1.1572 per 100 mg of declared elemental magnesium (prices observed 2026-10-26 to 2026-11-02); one offer gives no median. One offer means one ASIN and observation date; 1 observations are on review; their pack or dose has not passed the match checks. The ranked price uses the label's declared elemental amount.
computedFewer than three offers are ranked, so no distribution band is shown.
Chart data
| Displayed chart text |
|---|
| n=1 |
| median $1.1572 |
| Rank | Label | EC100 | Match and observation |
|---|---|---|---|
| 1 | Momentous Magnesium Threonate | $1.1572 per 100 mg | confirmed; 2026-11-02 · $49.99 for 90 units |
| On review | Dr. Mercola Magnesium Advanced | No ranked EC100 | the filed elemental amount (2000 mg per serving) is likely the compound mass; 2026-09-21 |
Verified: a row matched to the label by hand in August 2026 that passes every automatic check. Confirmed: brand, salt and dose match the label in the September 2026 check. Only these two are ranked; rows on review are not.
single offer
Source · Amazon via licensed data provider · Unique ASIN and observation date; prices observed 2026-10-26 to 2026-11-02 · release 2026-08-10-f441aa9f · CSV · method
What else is in L-threonate labels, including stearate, shells and fillers?
8 named excipients appear in the top displayed list among 8 labels naming L-threonate as of 2026-08-10. A listed ingredient is a filed name, not a quantified mass; open the underlying label to check context and capsule material.
measured
Chart data
| Displayed chart text |
|---|
| hypromellose |
| 4 |
| microcrystalline cellulose |
| 3 |
| silicon dioxide |
| ascorbyl palmitate |
| 2 |
| hydroxypropyl cellulose |
| rice flour |
| cellulose |
| 1 |
| gelatin |
| microcrystalline |
| hydroxypropyl |
| Filed ingredient | Labels |
|---|---|
| hypromellose | 4 of 8 |
| microcrystalline cellulose | 3 of 8 |
| silicon dioxide | 3 of 8 |
| ascorbyl palmitate | 2 of 8 |
| hydroxypropyl cellulose | 2 of 8 |
| rice flour | 2 of 8 |
| cellulose | 1 of 8 |
| gelatin | 1 of 8 |
Source · NIH DSLD full label ingredient fields · Labels naming this salt; 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What did studies measure about absorption and side effects for L-threonate?
No study involving L-threonate is in our PubMed checked registry of 16 as of 2026-08-10. No side effect outcome for this salt can be reported from this set; use the linked registry to inspect the included studies.
measuredNo study involving L-threonate is in our registry as of 2026-11-02.
| Year | Study design and measured outcome | PubMed |
|---|---|---|
| No included study | No measurement for this salt | Registry checked 2026-08-10 |
Source · PubMed checked study registry · Registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which labels file L-threonate, and how much do they declare per serving?
8 labels name L-threonate; 7 have a computable elemental amount per serving, with median 144 mg, against the full list linked below. The first eight are shown here. Values are filed elemental magnesium, not an assay of the contents, in the NIH DSLD snapshot 2026-08-10.
measured
Chart data
| Displayed chart text |
|---|
| P10 144 mg |
| P50 144 mg |
| P90 146 mg |
| Label | Declared elemental per serving | NIH DSLD |
|---|---|---|
| Dr. Mercola Magnesium Advanced | 145 mg | 327131 |
| Dr. Mercola Magnesium Advanced | Not determined | 327132 |
| Momentous Magnesium Threonate | 144 mg | 321465 |
| Nootropics Depot Magtein Magnesium L-Threonate Powder | 144 mg | 232390 |
| Protocol For Life Balance Magtein Magnesium L-Threonate | 144 mg | 326454 |
| Source Naturals Magtein Magnesium L-Threonate 667 mg | 147 mg | 274903 |
| Teraputics Pure Life Magnesium L-Threonate | 144 mg | 245277 |
| The Vitamin Shoppe Magnesium Threonate | 144 mg | 213752 |
Source · NIH DSLD on-market labels · Labels naming this salt; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Where do these numbers come from, and how do I cite or correct them?
The 8 recognized L-threonate labels come from the NIH DSLD snapshot 2026-08-10. Chemistry was calculated from molecular formulas on 2026-10-17; observed retail prices are checked 2026-11-02. The linked CSV carries only values displayed on this page. Cite the release and report a claim if a filed label or calculation needs correction.
computed| Layer | Source and date |
|---|---|
| Labels | NIH DSLD snapshot 2026-08-10 |
| Chemistry | Formula calculation 2026-10-17 |
| Retail | Prices observed 2026-10-26 to 2026-11-02 |
Source · NIH DSLD; chemical formulas; Amazon via licensed data provider · Release 2026-08-10-f441aa9f · release 2026-08-10-f441aa9f · CSV · method