Label arithmetic · NIH DSLD 314544
tnvitamins Magnesium Glycinate 300 mg: 150 mg of magnesium per capsule, 2 capsules a day, $8.66 a month
150 mg of magnesium per capsule; the label's 2 capsules a day cost $8.66 a month (Amazon, Nov 2). Inside: salt weight, capsule size, price rank.
tnvitamins Magnesium Glycinate 300 mg declares 300 mg of elemental magnesium per serving as glycinate, which needs 1,064–1,268 mg of magnesium glycinate in each capsule, against 1,100 mg in the largest standard capsule (size 000) at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range: it fits only that size. Observed at $0.0962 per 100 mg, rank 3 of 17 ranked glycinate offers (1 = lowest price per 100 mg), percentile 18 (lower = lower price). NIH DSLD 314544, label dated 2024-06-20.
computed from the filed label
Chart data
| Displayed chart text |
|---|
| 545 mg |
| 730 mg |
| 1,100 mg |
| 1,064–1,268 mg of glycinate per capsule |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-11-02 · chemistry 2026-10-17
Mass: 1,064–1,268 mg per capsule · Price: $0.0962 per 100 mg · % DV: 71% vs 71%
Elemental: The magnesium itself; the rest of the compound weight is the partner molecule.
Compound: The whole salt, such as magnesium glycinate, that must physically fit in the capsule.
Size 000: The largest standard capsule, about 1,100 mg of powder at 0.8 g/mL, the top of the usual 0.6–0.8 range; size 00 holds about 730 mg and size 0 about 545 mg.
Recompute with your price
Enter the price you paid; the declared amount and servings of this label are prefilled, so the result is the cost per 100 mg of elemental magnesium for your bottle.
Same-salt comparison appears here.
Will 300 mg of glycinate actually fit in one capsule, or do I need more than one?
Estimated salt mass versus assumed capsule capacity: tnvitamins Magnesium Glycinate 300 mg implies 1,064–1,268 mg of magnesium glycinate in each capsule to deliver 300 mg of elemental magnesium, against 1,100 mg in the largest standard capsule (size 000) at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range. Verdict: needs size 000, read at the most favourable hydration and the most units per serving.
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | 300 mg |
| Units per serving | 2 |
| Magnesium glycinate per serving | 2,128–2,536 mg |
| Magnesium glycinate per capsule | 1,064–1,268 mg |
| Capsule capacity 0 · 00 · 000 | 545 · 730 · 1,100 mg |
| Verdict | Needs size 000 |
The filed salt can have more than one hydration state (bisglycinate; chelate hydration varies by supplier), so the compound mass is a range.
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
tnvitamins Magnesium Glycinate 300 mg files 1 magnesium line in NIH DSLD 314544; the selected primary line declares 300 mg of elemental magnesium per serving, against 0 other rows excluded from the primary amount. A salt named under another nutrient does not turn that nutrient's quantity into elemental magnesium.
measured| Filed amount | Salt or note as filed | Role |
|---|---|---|
| 300 mg | Salt not named in this row; magnesium glycinate is taken from the label text | Primary serving |
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's glycinate claim hold up, or could the magnesium come from another source?
The label names one magnesium form, glycinate, resolved from the full NIH DSLD record text; at that salt the declaration is within the assumed size 000 capacity at powder density 0.8 g/mL, compared with oxide, the salt richest in magnesium at 60.3%.
computed with assumption| Form named on the label | Elemental fraction | Source |
|---|---|---|
| Magnesium glycinate | 11.8–14.1% | full NIH DSLD record text |
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Is this a good price for the elemental magnesium I'm actually getting?
tnvitamins Magnesium Glycinate 300 mg costs $0.0962 per 100 mg of elemental magnesium at the price observed 2026-11-02, rank 3 of 17 ranked glycinate offers (1 = lowest price per 100 mg), percentile 18 (lower = lower price), against a same-salt median of $0.1889; prices observed 2026-10-26 to 2026-11-02. First observed 2026-10-12 at $12.99, latest 2026-11-02 at $12.99, 3 observations.
computed
Chart data
| Displayed chart text |
|---|
| n=17 |
| P25 $0.1338 |
| P75 $0.2216 |
| median $0.1889 |
| Rank | Label | Per 100 mg | Observed |
|---|---|---|---|
| 1 | Amazon Elements Chelated Magnesium 270 mg | $0.0666 | 2026-11-02 |
| 2 | Solgar Chelated Magnesium | $0.0930 | 2026-11-02 |
| 3 | tnvitamins Magnesium Glycinate 300 mg | $0.0962 | 2026-11-02 |
| 4 | New Chapter Magnesium + Ashwagandha | $0.1229 | 2026-11-02 |
| 5 | Windmill Magnesium Glycinate 200 mg | $0.1338 | 2026-11-02 |
| Median | 17 ranked glycinate offers | $0.1889 | 2026-11-02 |
Source · Amazon via licensed data provider; NIH DSLD · unique ASIN × date; prices observed 2026-10-26 to 2026-11-02 · release 2026-08-10-f441aa9f · CSV · method
How many days will this bottle last at the label's own serving, and what does a day cost?
At the label's own serving, tnvitamins Magnesium Glycinate 300 mg lasts 45 days: 45 servings against 1 serving a day in the filed directions. $8.66 a month at the label's suggested use (2 capsules a day) and $12.12 at the 420 mg Daily Value reference (21 CFR 101.9); arithmetic on the label, not intake advice.
computed| Measure | Value |
|---|---|
| Net contents as filed | 90 Capsule(s) |
| Serving size as filed | 2 Capsule(s) |
| Servings per container | 45 |
| Servings per day in the directions | 1 |
| Days per bottle | 45 days |
| Cost a month at the label suggested use | $8.66 a month at the label's suggested use (2 capsules a day) |
| $ per 30 days at 420 mg Daily Value | $12.12 |
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "71% Daily Value" mean here, and does it recompute?
The label declares 71% Daily Value; 300 mg against the 420 mg reference in 21 CFR 101.9 recomputes to 71%, the same within one point.
computed| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 71% | 420 mg | 71% |
Source · NIH DSLD 314544; 21 CFR 101.9 · label 2024-06-20 · release 2026-08-10-f441aa9f · CSV · method
Why does this label contain magnesium stearate, what shell is it, and who is it filed for?
tnvitamins Magnesium Glycinate 300 mg files 3 other ingredients, including magnesium stearate (reference fraction 4.1% magnesium; no quantity filed, so it is not added to the total) and a gelatin shell, against 28 of 73 glycinate labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Magnesium Stearate |
| 2 | Microcrystalline Cellulose |
| 3 | Gelatin |
| Shell | gelatin |
| Target group | Adult (18 - 50 Years) |
| Target group | Gluten Free |
| Target group | Dairy Free |
| Target group | Sugar Free |
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about glycinate, and about side effects?
6 studies in the PubMed-checked registry measured outcomes involving glycinate; 2 mention gastrointestinal or adverse outcomes. They measured the salt, not this label.
measured| Year | Study | PubMed |
|---|---|---|
| 2024 | Comparative Clinical Study on Magnesium Absorption and Side Effects After Oral Intake of Microencapsulated Magnesium (MAGSHAPE™ Microcapsules) Versus Other Magnesium Sources. | 39770988 |
| 2024 | The bioaccessibility and tolerability of marine-derived sources of magnesium and calcium. | 38608850 |
| 2020 | Dose-Dependent Absorption Profile of Different Magnesium Compounds | 30761462 |
Source · PubMed-checked study registry · registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Has this brand had FDA recalls or adverse event reports?
tnvitamins has 2 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. tnvitamins has no FDA CAERS adverse event report on record at brand level as of 2026-10-19 (143 of 273 brands in this registry have at least one CAERS report).
measured| Recall | Date | Reason | Status |
|---|---|---|---|
| H-0942-2026 | 2026-06-17 | Product may be contaminated with Salmonella. | Ongoing |
| H-1185-2026 | 2026-07-29 | Contaminated with Salmonella | Ongoing |
Source · openFDA enforcement and CAERS · queried 2026-10-19 · release 2026-08-10-f441aa9f · CSV · method
Is this the same formula as another brand's, and how do their prices differ?
No other brand files the same formulation (ingredients, shell, units and rounded amount) as of 2026-11-02.
computed| Label | Brand | Price per 100 mg |
|---|---|---|
| No cross-brand match as of 2026-11-02 |
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which labels are closest to this one, with the same salt and dose?
3 labels use the same resolved glycinate within ±10% of this label's 150 mg per unit, compared side by side on price and capsule verdict.
computed| Label | Elemental per unit | Price | Verdict |
|---|---|---|---|
| NFH Magnesium SAP (DSLD 273081) | 150 mg | No price | Needs size 000 |
| NFH Magnesium SAP (DSLD 273582) | 150 mg | No price | Needs size 000 |
| Amazon Elements Chelated Magnesium 270 mg | 135 mg | $21.59 · 2026-11-02 | Capsule sizes do not apply |
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Where does this record come from, what is missing, and how do I cite or correct it?
Every value on this page traces to NIH DSLD 314544 (label 2024-06-20, snapshot 2026-08-10), a price observed 2026-11-02 and the chemistry model of 2026-09-13. No data gap remains for the computed fields. The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 314544 |
| Scanned label (PDF) | Label 314544 scan |
| Label date | 2024-06-20 |
| Date entered into DSLD | 2024-06-20 |
| Barcode (UPC) as filed | X003AI3JJ9 |
| Manufactured and Laboratory Tested for | Total Nutrition Inc, Farmingdale, NY |
| Claim category as filed | Nutrient |
| Claim category as filed | All Other |
13 additional rows
| Field | As filed |
|---|---|
| Suggested/Recommended/Usage/Directions | Directions: As a dietary supplement for adults, take two (2) capsules daily, or as directed by a healthcare professional. |
| Precautions re: Pregnant or Nursing or Prescription Medications | Caution: Pregnant or lactating women should consult a doctor before use. |
| Precautions re: All Other | If you are under medical supervision, please consult a doctor before use. Discontinue use and consult a doctor if any adverse reactions occur. |
| Precautions re: Children | Keep out of reach of children. |
| Storage | Store in a cool, dry place. |
| General Statements: All Other Content | New |
| Formula re: Contains | Highly absorbable chelated Magnesium Glycinate |
| FDA Statement of Identity | Dietary Supplement |
| Seals/Symbols | Packaged & lab tested in the USA |
| Formulation re: Other | 100% natural |
| Formulation re: Does NOT Contain | Non GMO Gluten free Nuts free Free of: gluten, wheat, yeast, soy, peanuts, tree nuts, fish, crustaceans, sugar, & dairy. No artificial colors or flavors. Non-GMO. |
| Physical state | Capsule |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 314544 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
6 brand pages linked below contain magnesium labels from the NIH DSLD registry snapshot dated 2026-08-10.