Label arithmetic · NIH DSLD 336938
tnvitamins Magnesium Citrate 800 mg: the label lists 800 mg, salt or magnesium?
The label lists 800 mg; if that is citrate weight, it holds 90–129 mg of magnesium. No US price matched (Nov 2). Inside: salt weight, capsule size.
tnvitamins Magnesium Citrate 800 mg declares magnesium without one determinable amount per 2 capsule(s); Capacity audit excluded as of 2026-10-17: the filed amount may describe compound mass rather than elemental magnesium; the elemental amount is unresolved., as of 2026-11-02. No US retail price matched as of 2026-11-02; 17 of the 135 citrate labels in this registry have a matched price. NIH DSLD 336938, label dated 2025-08-22.
as filedData release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-10-19 · chemistry 2026-10-17
Mass: not computable · Price: none matched · % DV: 30% vs n/a%
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 the declared mg of citrate actually fit in one capsule, or do I need more than one?
The compound mass behind this label cannot be computed as of 2026-11-02: Capacity audit excluded as of 2026-10-17: the filed amount may describe compound mass rather than elemental magnesium; the elemental amount is unresolved.. The filed amounts are listed in the next block. No lower bound: Capacity audit excluded as of 2026-10-17: the filed amount may describe compound mass rather than elemental magnesium; the elemental amount is unresolved..
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | Not one amount as of 2026-11-02 |
| Units per serving | 2 |
| Magnesium citrate per serving | Not computable as of 2026-11-02 |
| Magnesium citrate per capsule | Not computable as of 2026-11-02 |
| Capsule capacity 0 · 00 · 000 | 545 · 730 · 1,100 mg |
| Verdict | Not computable as of 2026-11-02 |
The filed salt can have more than one hydration state (trimagnesium dicitrate 16.2%; dibasic and hydrated forms as low as 11.3%), so the compound mass is a range.
Source · NIH DSLD 336938 · label 2025-08-22; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does the label's own text add up on magnesium?
The label's ingredient rows list 800 mg of magnesium citrate and 128 mg of magnesium: 128 mg of magnesium from 800 mg of magnesium citrate is 16.0% magnesium, against the 11.3–16.2% that magnesium citrate can carry, so the label's numbers agree with its salt.
computed| Measure | Value |
|---|---|
| Ingredient rows (NIH DSLD) | 800 mg magnesium citrate · 128 mg magnesium |
| Implied magnesium share | 16.0% |
| Most magnesium citrate can carry | 16.2% |
Source · NIH DSLD 336938 label text · snapshot 2026-08-10; salt fractions from the chemistry model · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
tnvitamins Magnesium Citrate 800 mg files 2 magnesium lines in NIH DSLD 336938; 2 primary lines give no single elemental amount, 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.
computed with assumption| Filed amount | Salt or note as filed | Role |
|---|---|---|
| 800 mg | Salt not named in this row; magnesium citrate is taken from the label text | Primary serving |
| 128 mg | Salt not named in this row; magnesium citrate is taken from the label text | Primary serving |
If 800 mg were the compound mass rather than the element, the elemental amount would be about 129 mg (16.2% of it), computed with a stated assumption.
Source · NIH DSLD 336938 · label 2025-08-22; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's citrate claim hold up, or could the magnesium come from another source?
The label names one magnesium form, citrate, resolved from the full NIH DSLD record text; capsule capacities do not apply to this form, compared with oxide, the salt richest in magnesium at 60.3%.
computed with assumption| Form named on the label | Elemental fraction | Source |
|---|---|---|
| Magnesium citrate | 11.3–16.2% | full NIH DSLD record text |
Source · NIH DSLD 336938 · label 2025-08-22; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Is this a good price for the elemental magnesium I'm actually getting?
No US retail price is matched to this label as of 2026-11-02; 17 of 135 citrate labels have one, against a median of $0.1159 per 100 mg among 12 ranked citrate offers.
computed
Chart data
| Displayed chart text |
|---|
| n=12 |
| P25 $0.0843 |
| P75 $0.1469 |
| median $0.1159 |
| Rank | Label | Per 100 mg | Observed |
|---|---|---|---|
| 1 | Best Naturals Magnesium Citrate 200 mg | $0.0344 | 2026-11-02 |
| 2 | Solgar Magnesium Citrate | $0.0607 | 2026-11-02 |
| 3 | LES Labs Magnesium Citrate | $0.0777 | 2026-11-02 |
| 4 | Bluebonnet Magnesium Citrate | $0.0865 | 2026-11-02 |
| 5 | Solaray Magnesium Citrate 400 mg | $0.0868 | 2026-11-02 |
| Median | 12 ranked citrate offers | $0.1159 | 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 Citrate 800 mg lasts 60 days: 60 servings against 1 serving a day in the filed directions.
computed| Measure | Value |
|---|---|
| Net contents as filed | 120 Capsule(s) |
| Serving size as filed | 2 Capsule(s) |
| Servings per container | 60 |
| Servings per day in the directions | 1 |
| Days per bottle | 60 days |
| $ per 30 days at one label serving a day | No ranked price as of 2026-11-02 |
| $ per 30 days at 420 mg Daily Value | No ranked price as of 2026-11-02 |
Source · NIH DSLD 336938 · label 2025-08-22; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "30% Daily Value" mean here, and does it recompute?
The label declares 30% Daily Value for "Adults and children 4 or more years of age", a group whose reference is not resolved as of 2026-11-02.
computed| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 30% | 420 mg | Not computable |
Source · NIH DSLD 336938; 21 CFR 101.9 · label 2025-08-22 · 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 Citrate 800 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 43 of 135 citrate labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Microcrystalline Cellulose |
| 2 | Magnesium Stearate |
| 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 336938 · label 2025-08-22; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about citrate, and about side effects?
10 studies in the PubMed-checked registry measured outcomes involving citrate; 1 mention gastrointestinal or adverse outcomes. They measured the salt, not this label.
measured| Year | Study | PubMed |
|---|---|---|
| 2025 | Comparing the Bioavailability of Two Seawater-Derived Magnesium Preparations. | 40955524 |
| 2024 | Comparative Clinical Study on Magnesium Absorption and Side Effects After Oral Intake of Microencapsulated Magnesium (MAGSHAPE™ Microcapsules) Versus Other Magnesium Sources. | 39770988 |
| 2022 | Effects of short-term magnesium supplementation on ionized, total magnesium and other relevant electrolytes levels. | 35041150 |
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 336938 · label 2025-08-22; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which labels are closest to this one, with the same salt and dose?
No other label files the same resolved salt within ±10% of this label's dose per unit as of 2026-11-02.
computed| Label | Elemental per unit | Price | Verdict |
|---|---|---|---|
| No neighbour as of 2026-11-02 |
Source · NIH DSLD 336938 · label 2025-08-22; 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 336938 (label 2025-08-22, snapshot 2026-08-10) and the chemistry model of 2026-09-13. 2 gaps remain: Capacity audit excluded as of 2026-10-17: the filed amount may describe compound mass rather than elemental magnesium; the elemental amount is unresolved.; No US retail price matched as of 2026-11-02 (barcode X0040F5M91). The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 336938 |
| Scanned label (PDF) | Label 336938 scan |
| Label date | 2025-08-22 |
| Date entered into DSLD | 2025-08-22 |
| Barcode (UPC) as filed | X0040F5M91 |
| 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. |
| General Statements: All Other Content | New 120 caps |
| 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. |
| Formula re: Contains | Magnesium Citrate 800 mg per serving |
| FDA Statement of Identity | Dietary Supplement |
| Formulation re: Does NOT Contain | Non-GMO, Gluten-free 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. |
| Seals/Symbols | Packaged & lab tested in the USA |
| Formulation re: Other | 100% Natural |
| Physical state | Capsule |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 336938 · label 2025-08-22; 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.