Label arithmetic · NIH DSLD 224740

GNC Magnesium 500 mg

GNC Magnesium 500 mg declares 500 mg of elemental magnesium as oxide, which needs 829 mg of salt per unit — a size 000 capsule or larger; NIH DSLD 224740, label dated 2020-06-24, calculation 2026-09-13.

FDA recall records for GNC: 3 · queried 2026-09-13; brand-string matches across products.

Mass budget · computed; capsule comparison · modelled

What the declared salt would weigh

GNC Magnesium 500 mg declares 500 mg of elemental magnesium per serving in NIH DSLD 224740, requiring 828.91 mg of magnesium oxide under the salt model calculated 2026-09-13.

Elemental-to-compound conversion for NIH DSLD 224740
StepValueEvidence
Declared elemental magnesium500 mg per servingobserved · label 2020-06-24
Resolved saltMagnesium oxide · label-rowcomputed · name resolved from filed text
Reference formulaMgO; 40.3 g/molcomputed · chemical reference
Elemental fraction60.32% by masscomputed
Compound mass per serving828.91 mg = 500 mg ÷ elemental fractioncomputed
Compound mass per discrete unit828.91 mgcomputed

At powder density 0.6–0.8 g/mL, 829 mg of powder requires the largest standard size, 000 (holds about 1,100 mg).

The verdict uses the most favourable reading for the product — the smallest compound mass the label allows. It excludes the shell and other ingredients; their unreported masses are not added as guesses.

Size 0 holds about 545 mg, size 00 about 730 mg, and size 000 about 1,100 mg at powder density 0.6–0.8 g/mL. These are model inputs, not measurements of this product's capsule. Read the mass-budget method.

Label facts and derived measurements

The numbers for this label

GNC Magnesium 500 mg has 11 published fields below, traced to NIH DSLD 224740 and the 2026-08-10 registry snapshot, with calculations dated 2026-09-13.

Values published in this page's Product metadata
FieldValueEvidence tier
NIH DSLD identifier224740observed
Resolved saltMagnesium oxidecomputed
Source of the resolved saltlabel-rowobserved
Elemental magnesium per serving (mg)500observed
Servings per containerServings not filed as of 2026-09-13observed
Elemental magnesium per container (mg)Container magnesium not computable as of 2026-09-13computed
Compound mass per discrete unit828.91 mgcomputed
Capsule fill verdictneeds-000modelled
Required standard capsule size000modelled
Label date2020-06-24observed
Retail match confidenceunmatchedcomputed

Observed means a value transcribed from a label or price observation. Computed means arithmetic or normalization of those inputs. Modelled means the result depends on a stated physical assumption, including capsule capacity. Evidence tiers and their limits.

Source transcription · observed

Magnesium lines as filed

GNC Magnesium 500 mg retains 1 magnesium-related rows in NIH DSLD 224740, including 1 rows selected for the primary serving, from label 2020-06-24, examined 2026-09-13.

Filed amounts, salt names and serving order
Filed amountServing orderFiled salt / notesCalculation role
500 mg1oxide

Magnesium (Form: as Magnesium Oxide)

Selected primary serving

The elemental amount comes from the selected magnesium line. A salt named under another nutrient does not make that nutrient's quantity an elemental magnesium value. Distinct unresolved primary amounts remain ambiguous; they are not added together.

Package arithmetic · observed inputs, computed totals

What the package works out to

GNC Magnesium 500 mg has no filed serving count for package arithmetic in NIH DSLD 224740, according to label 2020-06-24, calculated 2026-09-13.

Arithmetic using the label's own serving, not intake advice
Net contents as filed120 Capsule(s)
Discrete units in the package120
Serving size as filed1 Capsule(s)
Units per serving1
Servings per packageServings not filed as of 2026-09-13
Daily servings in the label instructions1
Days per package at the label's own servingDays not computable from filed frequency and serving count as of 2026-09-13

Days = filed servings per container ÷ filed servings per day. If the label gives a frequency range, the largest frequency gives the shortest duration. Cost per serving = observed item price ÷ filed servings; cost per label-day multiplies this by the filed frequency. This follows the label's own instructions; it is package arithmetic, not intake advice.

Percent daily value · observed and computed

The label's percent daily value, recomputed

GNC Magnesium 500 mg files 1 magnesium percent-daily-value entries in NIH DSLD 224740; the check below applies the group-specific references in 21 CFR 101.9 to its 500 mg primary serving, calculated 2026-09-13.

Declared values and current-reference arithmetic
Group as filedDeclaredReferenceRecomputedDifference
Adults and children 4 or more years of age119%420 mg119%0 percentage points

Percent daily value = declared elemental mg ÷ the group's reference mg × 100, rounded to an integer. The adult and age-four-plus reference is 420 mg. Historical labels can use earlier references; a difference does not establish a filing error. Full-record entries may cover multiple serving sizes, so this table identifies the primary-serving basis explicitly. Group references and interpretation.

Composition · observed

Other ingredients in the filed record

GNC Magnesium 500 mg lists 4 other ingredients in NIH DSLD 224740, label dated 2020-06-24, examined 2026-09-13.

Other ingredients as filed
EntryIngredient
1Microcrystalline Cellulose
2Gelatin
3Stearic Acid
4Magnesium Stearate

Capsule material: gelatin. The material classification follows the filed ingredient names; it is not a test of the shell.

This label lists magnesium stearate, whose reference elemental fraction is 4.1% by mass. No stearate quantity is available in this record as of 2026-09-13, so its magnesium contribution cannot be quantified or added to the Supplement Facts magnesium total.

Label declarations · observed

Target groups as filed

GNC Magnesium 500 mg has 4 target-group entries in NIH DSLD 224740, label dated 2020-06-24, examined 2026-09-13.

Manufacturer-filed target groups
EntryFiled group
1Adult (18 - 50 Years)
2Gluten Free
3Dairy Free
4Sugar Free

Provenance · observed

Registry record, versions and scanned label

The registry holds 3 versions of this label for GNC Magnesium 500 mg, according to the retained record examined 2026-09-13; the label date is 2020-06-24.

Source record for GNC Magnesium 500 mg
NIH DSLD labelNIH DSLD 224740
Registry snapshot2026-08-10
Label date2020-06-24
Physical stateCapsule
Barcode as filed0 48107 20578 2
Versions held by the registry3; version details are not available in this enrichment record as of 2026-09-13
Calculation date2026-09-13

The barcode is retained as an identifier, not as proof of a retail match. A registry version count records the number held; it does not reveal what changed. The label date, registry snapshot and price-observation date describe different events.

Gaps in this record

What is not available for this label

GNC Magnesium 500 mg has 2 unresolved data gaps in the retained NIH DSLD and price records as of 2026-09-13.

Dated missing-data statements
EntryKnown gap
1No confirmed US retail price matched to NIH DSLD 224740 (barcode 0 48107 20578 2) as of 2026-09-13.
2Servings per container are not filed; container magnesium and package duration cannot be computed as of 2026-09-13.

An unmatched retail price describes our matching coverage. It does not establish that a product is unavailable. The elemental cost calculator can apply the same EC100 formula to a price you supply.