Label arithmetic · NIH DSLD 208431
Source Naturals Magnesium Malate 625 mg: 425 mg of magnesium per serving, 2–6 capsules a day
425 mg of magnesium per serving. No US price matched (Nov 2). Inside: salt weight, capsule size.
Source Naturals Magnesium Malate 625 mg declares 425 mg of elemental magnesium per serving as malate, which needs 456–561 mg of magnesium malate in each capsule, against 545 mg in a size 0 capsule at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range: it fits a size 0 capsule, the smallest of the three sizes compared here. No US retail price matched as of 2026-11-02; 2 of the 20 malate labels in this registry have a matched price. NIH DSLD 208431, label dated 2019-11-21.
computed from the filed label
Chart data
| Displayed chart text |
|---|
| 545 mg |
| 730 mg |
| 1,100 mg |
| 456–561 mg of malate per capsule |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-10-19 · chemistry 2026-10-17
Mass: 456–561 mg per capsule · Price: none matched · % DV: 106% vs 101%
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 425 mg of malate actually fit in one capsule, or do I need more than one?
Estimated salt mass versus assumed capsule capacity: Source Naturals Magnesium Malate 625 mg implies 456–561 mg of magnesium malate in each capsule to deliver 425 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: fits size 0, read at the most favourable hydration and the most units per serving.
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | 425 mg |
| Units per serving | 2–6 |
| Magnesium malate per serving | 2,735–3,365 mg |
| Magnesium malate per capsule | 456–561 mg |
| Capsule capacity 0 · 00 · 000 | 545 · 730 · 1,100 mg |
| Verdict | Fits size 0 |
The filed salt can have more than one hydration state (anhydrous 15.54% or dihydrate 12.63% (192.41 g/mol)), so the compound mass is a range.
Source · NIH DSLD 208431 · label 2019-11-21; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
Source Naturals Magnesium Malate 625 mg files 1 magnesium line in NIH DSLD 208431; the selected primary line declares 425 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 |
|---|---|---|
| 425 mg | malate · Magnesium (Form: as Magnesium Malate) | Primary serving |
Source · NIH DSLD 208431 · label 2019-11-21; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's malate claim hold up, or could the magnesium come from another source?
The label names one magnesium form, malate, resolved from the filed magnesium line; 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 malate | 12.6–15.5% | filed magnesium line |
Source · NIH DSLD 208431 · label 2019-11-21; 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; 2 of 20 malate labels have one, against a median of $0.1052 per 100 mg among 4 ranked malate offers.
computed
Chart data
| Displayed chart text |
|---|
| n=4, band unstable |
| P25 $0.0739 |
| P75 $0.1402 |
| median $0.1052 |
| Rank | Label | Per 100 mg | Observed |
|---|---|---|---|
| 1 | Seeking Health Magnesium Malate 500 mg | $0.0460 | 2026-11-02 |
| 2 | BulkSupplements.com Magnesium Malate Capsules 400 mg | $0.0832 | 2026-11-02 |
| 3 | Trace Minerals Research Stress-X Magnesium Powder Lemon Lime | $0.1272 | 2026-11-02 |
| 4 | Thorne Calcium-Magnesium Malate | $0.1792 | 2026-11-02 |
| Median | 4 ranked malate offers | $0.1052 | 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, Source Naturals Magnesium Malate 625 mg lasts 16 days: 16 servings against 1 serving a day in the filed directions.
computed| Measure | Value |
|---|---|
| Net contents as filed | 100 Capsule(s) |
| Serving size as filed | 2–6 Capsule(s) |
| Servings per container | 16 |
| Servings per day in the directions | 1 |
| Days per bottle | 16 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 208431 · label 2019-11-21; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "106% Daily Value" mean here, and does it recompute?
The label declares 106% Daily Value; 425 mg against the 420 mg reference in 21 CFR 101.9 recomputes to 101%, 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 |
| 101 · 106 |
| Declared vs |
| recomputed % DV |
| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 106% | 420 mg | 101% |
Source · NIH DSLD 208431; 21 CFR 101.9 · label 2019-11-21 · release 2026-08-10-f441aa9f · CSV · method
Why does this label contain magnesium stearate, what shell is it, and who is it filed for?
Source Naturals Magnesium Malate 625 mg files 4 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 12 of 20 malate labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Gelatin |
| 2 | Microcrystalline Cellulose |
| 3 | Magnesium Stearate |
| 4 | Silica |
| Shell | gelatin |
| Target group | Adult (18 - 50 Years) |
| Target group | Gluten Free |
| Target group | Dairy Free |
1 additional rows
| Entry | Filed ingredient or declaration |
|---|---|
| Target group | Sugar Free |
Source · NIH DSLD 208431 · label 2019-11-21; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about malate, and about side effects?
3 studies in the PubMed-checked registry measured outcomes involving malate; none reports a gastrointestinal outcome as of 2026-11-02. They measured the salt, not this label.
measured| Year | Study | PubMed |
|---|---|---|
| 2020 | Dose-Dependent Absorption Profile of Different Magnesium Compounds | 30761462 |
| 2019 | Timeline (Bioavailability) of Magnesium Compounds in Hours: Which Magnesium Compound Works Best? | 29679349 |
| 2018 | Scottsdale Magnesium Study: Absorption, Cellular Uptake, and Clinical Effectiveness of a Timed-Release Magnesium Supplement in a Standard Adult Clinical Population. | 29425476 |
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?
Source Naturals has 6 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. Source Naturals 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 |
|---|---|---|---|
| F-0100-2014 | 2013-11-13 | The firm found small piece of metal fragment in one tablet during its inspection process. | Terminated |
| F-1100-2014 | 2013-12-25 | Dietary Supplements were made with bulk products provided by National Enzyme Company which are currently under recall for chloramphenicol | Terminated |
| F-2178-2017 | 2017-05-10 | Testing of Vitamin D-3 as a result of a consumer complaint found specific lots to have lower concentrations than product specifications of ingredient labeling. | Terminated |
| F-2380-2017 | 2017-07-19 | Dietary supplements contain low levels of undeclared boron | Terminated |
| F-2383-2017 | 2017-07-19 | Dietary supplements contain low levels of undeclared boron | Terminated |
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 208431 · label 2019-11-21; 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 208431 · label 2019-11-21; 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 208431 (label 2019-11-21, snapshot 2026-08-10) and the chemistry model of 2026-09-13. 1 gap remain: No US retail price matched as of 2026-11-02 (barcode 0 21078 01599 4). The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 208431 |
| Label date | 2019-11-21 |
| Date entered into DSLD | 2019-11-21 |
| Barcode (UPC) as filed | 0 21078 01599 4 |
| Label version · Image difference, same product | NIH DSLD 295974 |
| Manufactured for | Source Naturals, Inc., Santa Cruz, CA |
| Claim category as filed | Nutrient |
| Claim category as filed | All Other |
16 additional rows
| Field | As filed |
|---|---|
| Claim category as filed | Structure/Function |
| FDA Statement of Identity | Dietary Supplement |
| General Statements: All Other Content | Supports muscles and energy production |
| Seals/Symbols | Non GMO Validated |
| Formulation re: Does NOT Contain | Non GMO Validated |
| Suggested/Recommended/Usage/Directions | Suggested use: 2 to 6 capsules daily with a meal. |
| Precautions re: Pregnant or Nursing or Prescription Medications | Note: If you are pregnant, may become pregnant, or breastfeeding, consult your health care professional before using this product. |
| Formula re: Contains | Source Naturals Magnesium Malate is a compound of magnesium and malic acid. |
| General Statements: All Other Content | It supports proper muscle function, cardiovascular health, and energy production. |
| Formula re: Contains | Malic acid is a natural fruit acid that is present in most cells in the body and is an intermediate in the Krebs cycle, where energy is captured during the metabolism of carbs and fats. Magnesium is an essential cofactor for over 300 enzymatic reactions in metabolism, ATP synthesis and energy production. Magnesium plays important roles in muscle relaxation, because of its function as a cofactor for enzymes and because of its ability to counterbalance calcium in the cell. |
| Formulation re: Does NOT Contain | Hypoallergenic: contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance. |
| Precautions re: All Other | Do not use if either tamper-evident seal is broken or missing. |
| Precautions re: Children | Keep out of the reach of 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. |
| Physical state | Capsule |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 208431 · label 2019-11-21; 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.