Source Naturals magnesium labels

A Supplement Facts panel declares the element; the salt carrying it is heavier. Dividing each label's declared magnesium by its salt's elemental fraction gives the powder mass the serving must contain — and whether that fits a capsule.

Method and the corpus-wide figure: label mass-budget audit.

• 12 of 17 labels list magnesium stearate. Stearate is 4.1% magnesium by mass and that magnesium is not on the Supplement Facts line; the amount of stearate is not declared, so it cannot be quantified.
• 8 labels use a gelatin shell.
• 7 labels use a cellulose-based shell.

Filed declarations across this brand's labels: 5 distinct filed entries across 17 NIH DSLD labels, counted 2026-09-13; these are manufacturer statements.

• Adult (18 - 50 Years) — on 17 of 17 labels
• Gluten Free — on 14 of 17 labels
• Dairy Free — on 14 of 17 labels
• Sugar Free — on 10 of 17 labels
• Vegetarian — on 4 of 17 labels

• 7 of 17 labels do not name the magnesium salt in the filed record, so no compound mass can be computed for them.
• 16 of 17 labels have no US retail listing matched as of 2026-09-13. That is a matching gap on our side, not evidence of unavailability.

See all brands, all labels, or the priced form tables.

Filed composition facets

10 published excipient facets occur across 17 labels from Source Naturals in the NIH DSLD records, counted 2026-09-13.

• magnesium stearate: 12 of 17 labels.
• silicon dioxide: 12 of 17 labels.
• gelatin: 7 of 17 labels.
• stearic acid: 7 of 17 labels.
• microcrystalline cellulose: 6 of 17 labels.
• dicalcium phosphate: 5 of 17 labels.
• modified cellulose gum: 5 of 17 labels.
• gum acacia: 4 of 17 labels.
• citric acid: 1 of 17 labels.
• maltodextrin: 1 of 17 labels.

FDA recall records for this firm

The FDA enforcement database holds 6 recall records naming Source Naturals (queried 2026-09-13); 0 of them concern a magnesium product.

These are exact brand-string matches in the recalling-firm field or product description, including other products. A name match does not establish that two similarly named firms are the same legal entity. The recalling firm and recalled product are shown in each row.

FDA assigns 3 recall classes by the assessed hazard, using the FDA classification definitions, checked 2026-09-13:

• Class I: Exposure to or use of the violating product carries a reasonable probability of serious harm to health or death.
• Class II: Exposure or use may produce temporary or medically reversible harm; the probability of serious harm is remote.
• Class III: Adverse health consequences from exposure or use are unlikely.

Full FDA record register and matching method →