Label arithmetic · NIH DSLD 63457
Sundown Naturalist Magnesium 250 mg: 250 mg of magnesium per 1 caplet
250 mg of magnesium in each 1 caplet, about 0 servings per 100 Coated Caplet. Oxide is 60.3% magnesium. Inside: label lines, ingredients.
Sundown Naturalist Magnesium 250 mg declares 250 mg of elemental magnesium per serving as oxide, which means 414 mg of magnesium oxide compound in one 1 caplet(s), compared with 1,100 mg in the largest standard capsule; capsule verdicts do not apply to this other (e.g. tea bag). No US retail price matched as of 2026-11-02; 10 of the 61 oxide labels in this registry have a matched price. NIH DSLD 63457, label dated 2016-08-24.
computed from the filed label
Chart data
| Displayed chart text |
|---|
| gluconate |
| 4,266 |
| orotate |
| 3,439 |
| L-threonate |
| 3,030 |
| taurate |
| 2,803 |
| lactate |
| 2,082 |
| glycerophosphate |
| 2,000 |
| glycinate |
| 1,773 |
| malate |
| 1,609 |
| aspartate |
| 1,598 |
| citrate |
| 1,547 |
| sulfate |
| 1,238 |
| chloride |
| 979 |
| carbonate |
| 867 |
| hydroxide |
| 600 |
| oxide |
| 414 |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-10-19 · chemistry 2026-10-17
Mass: 414 mg per serving · Price: none matched · % DV: 63% vs 60%
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.
How much oxide compound is in one serving?
Sundown Naturalist Magnesium 250 mg carries 414 mg of magnesium oxide per serving for 250 mg of elemental magnesium, against 1,100 mg in the largest standard capsule; capsule capacities do not apply to this other (e.g. tea bag).
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | 250 mg |
| Units per serving | 1 |
| Magnesium oxide per serving | 414 mg |
| Magnesium oxide per serving | 414 mg |
| Capsule capacity 0 · 00 · 000 | 545 · 730 · 1,100 mg |
| Verdict | Capsule sizes do not apply |
Source · NIH DSLD 63457 · label 2016-08-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
Sundown Naturalist Magnesium 250 mg files 1 magnesium line in NIH DSLD 63457; the selected primary line declares 250 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 |
|---|---|---|
| 250 mg | oxide · Magnesium (Form: as Magnesium Oxide) | Primary serving |
Source · NIH DSLD 63457 · label 2016-08-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's oxide claim hold up, or could the magnesium come from another source?
The label names one magnesium form, oxide, resolved from the filed magnesium line; 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 oxide | 60.3% | filed magnesium line |
Source · NIH DSLD 63457 · label 2016-08-24; 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; 10 of 61 oxide labels have one, against a median of $0.0293 per 100 mg among 5 ranked oxide offers.
computed
Chart data
| Displayed chart text |
|---|
| n=5 |
| P25 $0.0258 |
| P75 $0.0356 |
| median $0.0293 |
| Rank | Label | Per 100 mg | Observed |
|---|---|---|---|
| 1 | Nutricost Magnesium Oxide | $0.0148 | 2026-11-02 |
| 2 | tnvitamins Magnesium Oxide 420 mg | $0.0258 | 2026-11-02 |
| 3 | Douglas Laboratories Magnesium Oxide | $0.0293 | 2026-11-02 |
| 4 | Wonder Labs Magnesium Oxide 400 | $0.0356 | 2026-11-02 |
| 5 | Carlson Magnesium Gels 400 mg | $0.0636 | 2026-11-02 |
| Median | 5 ranked oxide offers | $0.0293 | 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?
Days per bottle cannot be computed for Sundown Naturalist Magnesium 250 mg as of 2026-11-02: servings per container are not filed.
computed| Measure | Value |
|---|---|
| Net contents as filed | 100 Coated Caplet(s) |
| Serving size as filed | 1 Caplet(s) |
| Servings per container | Not filed as of 2026-11-02 |
| Servings per day in the directions | 1 |
| Days per bottle | Not computable as of 2026-11-02 |
| $ 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 63457 · label 2016-08-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "63% Daily Value" mean here, and does it recompute?
The label declares 63% Daily Value; 250 mg against the 420 mg reference in 21 CFR 101.9 recomputes to 60%, a difference of 3 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 |
| 60 · 63 |
| Declared vs |
| recomputed % DV |
| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 63% | 420 mg | 60% |
Source · NIH DSLD 63457; 21 CFR 101.9 · label 2016-08-24 · 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?
Sundown Naturalist Magnesium 250 mg files 4 other ingredients and a vegetarian shell, and no magnesium stearate, against 30 of 61 oxide labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Cellulose |
| 2 | Croscarmellose |
| 3 | Silica |
| 4 | Contains <2% of: |
| Shell | vegetarian |
| Target group | Vegetarian |
| Target group | Adult (18 - 50 Years) |
| Target group | Gluten Free |
1 additional rows
| Entry | Filed ingredient or declaration |
|---|---|
| Target group | Dairy Free |
Source · NIH DSLD 63457 · label 2016-08-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about oxide, and about side effects?
12 studies in the PubMed-checked registry measured outcomes involving oxide; 2 mention gastrointestinal or adverse outcomes. They measured the salt, not this label.
measured| Year | Study | PubMed |
|---|---|---|
| 2026 | Randomized, open-label study of the short-term pharmacokinetics of oral magnesium oxide in healthy volunteers. | 42091979 |
| 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?
Sundown Naturalist has 0 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. Sundown Naturalist 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 63457 · label 2016-08-24; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which labels are closest to this one, with the same salt and dose?
6 labels use the same resolved oxide within ±10% of this label's 250 mg per unit, compared side by side on price and capsule verdict.
computed| Label | Elemental per unit | Price | Verdict |
|---|---|---|---|
| Indiana Botanic Gardens Magnesium 250 mg | 250 mg | No price | Capsule sizes do not apply |
| Finest Nutrition Magnesium 250 mg | 250 mg | No price | Capsule sizes do not apply |
| Nature's Bounty Magnesium 250 mg (DSLD 65689) | 250 mg | No price | Capsule sizes do not apply |
| Vitamin World Magnesium 250 mg | 250 mg | No price | Capsule sizes do not apply |
| ShopRite Magnesium 250 mg | 250 mg | No price | Capsule sizes do not apply |
| Nature's Bounty Magnesium 250 mg (DSLD 72877) | 250 mg | No price | Capsule sizes do not apply |
Source · NIH DSLD 63457 · label 2016-08-24; 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 63457 (label 2016-08-24, snapshot 2026-08-10) and the chemistry model of 2026-09-13. 2 gaps remain: No US retail price matched as of 2026-11-02 (barcode 0 30768 05836 4); Servings per container are not filed as of 2026-11-02. The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 63457 |
| Label date | 2016-08-24 |
| Date entered into DSLD | 2016-08-24 |
| Barcode (UPC) as filed | 0 30768 05836 4 |
| Manufactured by | Rexall Sundown, Inc., Boca Raton, FL, USA |
| Claim category as filed | All Other |
| Claim category as filed | Structure/Function |
| Seals/Symbols | 100% Quality Assurance Laboratory Tested |
18 additional rows
| Field | As filed |
|---|---|
| General Statements: All Other Content | Supports Bone & Muscle Health |
| FDA Statement of Identity | Dietary Supplement |
| General Statements: All Other Content | IMPORTANT FACTS YOU SHOULD KNOW Magnesium, a major mineral, plays a vital role in maintaining proper bone mineralization.* In addition to supporting bone health, Magnesium is also involved in muscle contractions, cell health and energy metabolism.* |
| Suggested/Recommended/Usage/Directions | DIRECTIONS: FOR ADULTS, TAKE ONE (1) CAPLET DAILY, PREFERABLY WITH A MEAL. |
| Formulation re: Vegetarian/Vegan | Vegetarian Formula |
| Formulation re: Does NOT Contain | No yeast, wheat, gluten, milk or milk derivatives, lactose, preservatives, soy, artificial flavor, sodium. |
| Precautions re: Pregnant or Nursing or Prescription Medications | WARNING: If you are pregnant, nursing, taking any medications or have any medical condition, consult your doctor before use. |
| Precautions re: All Other | Discontinue use and consult your doctor if any adverse reactions occur. |
| Precautions re: Children | KEEP OUT OF REACH OF CHILDREN. |
| Storage | STORE AT ROOM TEMPERATURE AND AVOID EXCESSIVE HEAT. |
| Precautions re: All Other | TAMPER RESISTANT: DO NOT USE IF SEAL UNDER CAP IS BROKEN OR MISSING. |
| 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. |
| General Statements: All Other Content | Quality Guaranteed Lab Tested Laboratory tested to meet strict quality control standards for potency, purity and disintegration. 100% Quality Guaranteed. |
| General: Product/Version Code | Prod. No. 5836 04C B51484 |
| Brand IP Statement(s) re: (c), (TM), (SM) | 2016 |
| General Statements: All Other Content | Actual Size |
| Physical state | Other (e.g. tea bag) |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 63457 · label 2016-08-24; 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.