Label arithmetic · NIH DSLD 211503
Roex Magnesium Potassium: 200 mg of magnesium per capsule, 2 capsules a day – amino acid chelate + citrate + gluconate + oxide
200 mg of magnesium per capsule; the label's 2 capsules a day give 400 mg. Inside: label lines, ingredients.
Roex Magnesium Potassium declares 400 mg of elemental magnesium from an amino acid chelate. "Amino acid chelate" names a class of compounds rather than one defined substance, so no elemental fraction exists and the compound mass cannot be computed from the label. No US retail price matched as of 2026-11-02. NIH DSLD 211503, label dated 2020-01-25.
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: 100% vs 95%
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 400 mg of magnesium 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: Single-salt capacity audit excluded as of 2026-10-17: one salt with a defined elemental fraction is not resolved.. The filed amounts are listed in the next block. Lower bound, not a measurement: even if all 400 mg of magnesium per serving came from magnesium oxide (60.3% magnesium), the richest of the 4 forms named for magnesium on the label, each of the 2 capsules would need at least 332 mg of compound, so at this bound it needs at least a size 0 capsule (about 545 mg at 0.8 g/mL); the actual mix of forms may need more.
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | 400 mg |
| Units per serving | 2 |
| Magnesium salt per serving | Not computable as of 2026-11-02 |
| Magnesium salt 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 |
Source · NIH DSLD 211503 · label 2020-01-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
Roex Magnesium Potassium files 1 magnesium line in NIH DSLD 211503; the selected primary line declares 400 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 |
|---|---|---|
| 400 mg | amino acid chelate, citrate, gluconate, oxide · Magnesium (Form: from Magnesium Amino Acid Chelate, Magnesium Oxide, Magnesium Citrate, and Magnesium Gluconate) | Primary serving |
Source · NIH DSLD 211503 · label 2020-01-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's magnesium claim hold up, or could the magnesium come from another source?
The label names 4 magnesium forms (amino-acid-chelate, citrate, gluconate, oxide); a named blend does not establish how much magnesium each form contributes, so the resolved reading is the most favourable one, compared with oxide, the salt richest in magnesium at 60.3%.
computed with assumption| Form named on the label | Elemental fraction | Source |
|---|---|---|
| amino-acid-chelate | No defined fraction | named on label |
| Magnesium citrate | 11.3–16.2% | named on label |
| Magnesium gluconate | 5.9% | named on label |
| Magnesium oxide | 60.3% | named on label |
Source · NIH DSLD 211503 · label 2020-01-25; 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, and without a resolved salt there is no same-salt comparison.
computed| Rank | Label | Per 100 mg | Observed |
|---|
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, Roex Magnesium Potassium 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 211503 · label 2020-01-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "100% Daily Value" mean here, and does it recompute?
The label declares 100% Daily Value; 400 mg against the 420 mg reference in 21 CFR 101.9 recomputes to 95%, a difference of 5 points. Labels filed under the earlier 400 mg reference, or with a different filing basis, show gaps of this kind.
computed
Chart data
| Displayed chart text |
|---|
| Declared vs recomputed % |
| DV |
| 95 · 100 |
| Declared vs |
| recomputed % DV |
| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 100% | 420 mg | 95% |
Source · NIH DSLD 211503; 21 CFR 101.9 · label 2020-01-25 · release 2026-08-10-f441aa9f · CSV · method
Why does this label contain magnesium stearate, what shell is it, and who is it filed for?
Roex Magnesium Potassium files 5 other ingredients, including magnesium stearate (reference fraction 4.1% magnesium; no quantity filed, so it is not added to the total) and a vegetarian shell.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Hydroxypropyl Methylcellulose |
| 2 | Microcrystalline Cellulose |
| 3 | Magnesium Stearate |
| 4 | Citric Acid |
| 5 | Silica |
| Shell | vegetarian |
| Target group | Adult (18 - 50 Years) |
Source · NIH DSLD 211503 · label 2020-01-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about this form, and about side effects?
No study in the registry measured an unresolved salt as of 2026-11-02.
measured| Year | Study | PubMed |
|---|
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?
Roex has 0 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. Roex 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 211503 · label 2020-01-25; 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 211503 · label 2020-01-25; 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 211503 (label 2020-01-25, snapshot 2026-08-10) and the chemistry model of 2026-09-13. 3 gaps remain: Single-salt capacity audit excluded as of 2026-10-17: one salt with a defined elemental fraction is not resolved.; No US retail price matched as of 2026-11-02 (barcode 6 45245 53120 1); A single salt with a defined elemental fraction is unresolved as of 2026-11-02. The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 211503 |
| Label date | 2020-01-25 |
| Date entered into DSLD | 2020-01-25 |
| Barcode (UPC) as filed | 6 45245 53120 1 |
| Label version · Image difference, same product | NIH DSLD 153995 |
| Distributed by | BIN Science LLC, Englewood, CO, United States of America |
| Claim category as filed | All Other |
| Claim category as filed | Structure/Function |
14 additional rows
| Field | As filed |
|---|---|
| Formula re: Contains | Roex Magnesium and Potassium are minerals that play a critical role in the support of our overall health. |
| Formulation re: Other | These alkaline minerals are involved in hundreds of processes throughout the body. Most notably, magnesium and potassium help maintain healthy circulatory function, cardiac rhythm, bone structure and energy levels. |
| General Statements: All Other Content | Various factors deplete the body's reserves of these two nutrients, so replenishing to help the body stay balanced and healthy is needed. |
| Precautions re: Pregnant or Nursing or Prescription Medications | Warning: Consult your physician prior to use if you are pregnant, nursing, have a medical condition or are taking medications. |
| Precautions re: Children | Not intended for children. |
| 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. |
| Storage | Store at room temperature, in a dry place. |
| Precautions re: Children | Keep out of the reach of children. |
| Precautions re: All Other | Do not use if clear safety seal around bottle neck is broken or missing. |
| Formulation re: Other | Mineral/Electrolyte Support Supports healthy cardiac rhythm Supports proper muscle function Promotes healthy bones |
| FDA Statement of Identity | Dietary Supplement |
| Suggested/Recommended/Usage/Directions | Directions: Adults, take 2 capsules once daily, with 8 oz of water, preferably with a meal as a dietary supplement or as directed by your doctor. |
| Physical state | Capsule |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 211503 · label 2020-01-25; 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.