Label arithmetic · NIH DSLD 315677
Double Wood Supplements 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.
Double Wood Supplements 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 315677, label dated 2024-07-25.
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: 28% 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 315677 · label 2024-07-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does the label's own text add up on magnesium?
The label's own text says “no less than 14% elemental magnesium by weight”: 112 mg of magnesium from 800 mg of magnesium citrate is 14.0% magnesium, against the 11.3–16.2% that magnesium citrate can carry, so the label's numbers agree with its salt.
computed| Measure | Value |
|---|---|
| Label text (NIH DSLD statements) | no less than 14% elemental magnesium by weight |
| Implied magnesium share | 14.0% |
| Most magnesium citrate can carry | 16.2% |
Source · NIH DSLD 315677 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?
Double Wood Supplements Magnesium Citrate 800 mg files 2 magnesium lines in NIH DSLD 315677; 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.
measured| 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 |
| 112 mg | Salt not named in this row; magnesium citrate is taken from the label text | Primary serving |
Source · NIH DSLD 315677 · label 2024-07-25; 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 315677 · label 2024-07-25; 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, Double Wood Supplements Magnesium Citrate 800 mg lasts 90 days: 90 servings against 1 serving a day in the filed directions.
computed| Measure | Value |
|---|---|
| Net contents as filed | 180 Capsule(s) |
| Serving size as filed | 2 Capsule(s) |
| Servings per container | 90 |
| Servings per day in the directions | 1 |
| Days per bottle | 90 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 315677 · label 2024-07-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "28% Daily Value" mean here, and does it recompute?
The label declares 28% 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 | 28% | 420 mg | Not computable |
Source · NIH DSLD 315677; 21 CFR 101.9 · label 2024-07-25 · release 2026-08-10-f441aa9f · CSV · method
Why does this label contain these other ingredients, what shell is it, and who is it filed for?
Double Wood Supplements Magnesium Citrate 800 mg files 1 other ingredient and a vegetarian shell, and no magnesium stearate, against 43 of 135 citrate labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Hypromellose |
| Shell | vegetarian |
| Target group | Adult (18 - 50 Years) |
| Target group | Gluten Free |
Source · NIH DSLD 315677 · label 2024-07-25; 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?
Double Wood Supplements has 0 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. Double Wood Supplements has FDA CAERS adverse event reports on record at brand level, as do 143 of 273 brands in this registry; openFDA states that “there is no certainty that the reported event (adverse event) was actually due to the product” and that reports “cannot be used to estimate the incidence of these events.”
measured| Recall | Date | Reason | Status |
|---|---|---|---|
| No recall record as of 2026-10-19 |
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 315677 · label 2024-07-25; 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 315677 · label 2024-07-25; 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 315677 (label 2024-07-25, 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 8 50033 27224 6). The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 315677 |
| Scanned label (PDF) | Label 315677 scan |
| Label date | 2024-07-25 |
| Date entered into DSLD | 2024-07-25 |
| Barcode (UPC) as filed | 8 50033 27224 6 |
| Manufactured for | Double Wood LLC , Philadelphia, PA , United States |
| Claim category as filed | Nutrient |
| Claim category as filed | All Other |
17 additional rows
| Field | As filed |
|---|---|
| Claim category as filed | Structure/Function |
| Formula re: Contains | Product Information: Magnesium Citrate is a Magnesium preparation in salt form with Citric Acid in a 1:1 ratio. It is standardized to be no less than 14% elemental magnesium by weight. |
| Suggested/Recommended/Usage/Directions | Suggested Use: As a dietary supplement, take 1 serving per day. (2 capsules) |
| Storage | Storage: Store in a cool, dark place. Do not freeze or expose to moisture or heat above room temperature. |
| Seals/Symbols | Manufactured in USA |
| Formulation re: Does NOT Contain | Made with Non-GMO Ingredients Gluten Free |
| FDA Disclaimer Statement | These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. |
| Formula re: Contains | Magnesium Citrate 800 mg per serving |
| FDA Statement of Identity | Dietary Supplement |
| Precautions re: All Other | Warning: Do not exceed recommended dose. |
| Precautions re: Pregnant or Nursing or Prescription Medications | Pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement. |
| Precautions re: Children | Pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement. |
| Precautions re: All Other | Discontinue use and consult your doctor immediately if any adverse reactions occur. Do not use Magnesium citrate and operate heavy machinery until you know how it affects you. |
| Precautions re: Children | Keep out of the reach of children. |
| Precautions re: All Other | Do not use if safety seal is damaged or missing. |
| Physical state | Capsule |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 315677 · label 2024-07-25; 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.