Brand · NIH DSLD snapshot 2026-08-10
NOW magnesium supplements: 14 products in 5 forms, 95–800 mg of magnesium per serving
14 NOW magnesium products in 5 forms, led by citrate (6); median 400 mg of magnesium per serving. Inside: each product's mg and price.
NOW files 14 on-market magnesium labels in NIH DSLD using 5 salts, most often citrate (4 of 14); 0 of 5 audited capsule labels are above the assumed size 000 capacity at powder density 0.8 g/mL, against 8 of 137 across the registry. Median declared amount 400 mg per serving; 1 of 14 labels has a matched US price as of 2026-11-02. Snapshot 2026-08-10.
computed from filed labels
Chart data
| Displayed chart text |
|---|
| citrate |
| 4 |
| glycinate |
| 2 |
| aspartate |
| 1 |
| malate |
| oxide |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-11-02 · chemistry 2026-10-17
Elemental: The magnesium itself; the rest of the compound weight is the partner molecule.
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.
Estimated salt mass versus assumed capsule capacity
0 of 5 audited capsule labels are above the assumed size 000 capacity at powder density 0.8 g/mL, against 8 of 137 across the registry. 1 fit size 0 or 00 and 4 need size 000, at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range and the most favourable hydration.
computed with assumption
Chart data
| Displayed chart text |
|---|
| NOW |
| fits 1 of 5 |
| needs 000 4 of 5 |
| exceeds 0 of 5 |
| all audited |
| fits 82 of 137 |
| needs 000 47 of 137 |
| exceeds 8 of 137 |
| Verdict | NOW | All audited capsule labels |
|---|---|---|
| Fits size 0 or 00 | 1 of 5 | 82 of 137 |
| Needs size 000 | 4 of 5 | 47 of 137 |
| Exceeds size 000 | 0 of 5 | 8 of 137 |
Source · NIH DSLD labels; mass balance · recognized salt only; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which magnesium salts does NOW use, and how much compound does each need?
NOW files 5 salts, most often citrate (4 of 14) across 14 labels; for 100 mg of magnesium the lightest of them needs 166 mg of compound against 1,335 mg for the heaviest.
computed| Salt | Labels | Elemental fraction | Compound per 100 mg Mg |
|---|---|---|---|
| citrate | 4 | 11.3–16.2% | 619–885 mg |
| glycinate | 2 | 11.8–14.1% | 709–845 mg |
| aspartate | 1 | 7.5–15.6% | 639–1,335 mg |
| malate | 1 | 12.6–15.5% | 644–792 mg |
| oxide | 1 | 60.3% | 166 mg |
Source · NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How do NOW's prices compare within each salt?
1 of 14 NOW labels has a matched US price as of 2026-11-02; each is compared with the median of its own salt, never across salts, per 100 mg of declared elemental magnesium.
computed| Label | Salt | Per 100 mg | Same-salt median | Observed |
|---|---|---|---|---|
| NOW Magnesium & Potassium Aspartate | aspartate | On review | none | 2026-10-26 |
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
Does the FDA hold recall or adverse event records naming NOW?
The FDA enforcement data queried 2026-10-19 holds 12 recall records naming NOW, 0 of them about a magnesium product. CAERS holds adverse event reports naming the brand, as it does for 143 of 273 brands here; 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-1726-2013 | 2013-07-31 | It has been determined that this product contains an undeclared ingredient, licorice extract, which contains glycyrrhizin derived from licorice root. | Terminated |
| F-0770-2014 | 2013-12-25 | Firm is recalling dietary supplements containing a raw material which may contain >0.3 ppb chloramphenicol | Terminated |
| F-1537-2014 | 2014-02-26 | Digestive enzyme capsules manufactured by NOW Foods may contain the antibiotic chloramphenicol. | Terminated |
| F-1484-2017 | 2017-02-22 | Product's supplement fact panel incorrectly states that the product contains 75 mg (milligrams) of Molybdenum, when it actually contains 75 mcg (micrograms). | Terminated |
| F-0682-2019 | 2018-12-12 | NOW Health Group Inc. initiated a voluntary recall of NOW s Vitamin B-50 mg 100 Veg Caps product code 0420 because it is mislabeled as Vitamin B-50 mg 100 Veg Caps. | Terminated |
| F-1002-2020 | 2020-07-01 | The product tested positive for Salmonella enterica. | Terminated |
| F-0512-2021 | 2021-05-26 | Foreign capsules included in bottle. Undeclared ingredients. | Terminated |
| F-0869-2021 | 2021-08-04 | Specific lot of Organic Steel Cut Oats, may actually contain Organic Beet Sugar | Terminated |
FDA record register and matching method
Source · openFDA enforcement and CAERS · queried 2026-10-19 · release 2026-08-10-f441aa9f · CSV · method
What else goes into NOW's labels, and what do they declare?
2 of 14 NOW labels list magnesium stearate, 2 use a gelatin shell and 10 a cellulose shell; 7 distinct filed declarations appear across them. Listed ingredients are filed names, not quantities.
measured| Filed entry | Labels |
|---|---|
| silicon dioxide | 10 of 14 |
| hypromellose | 8 of 14 |
| stearic acid | 7 of 14 |
| ascorbyl palmitate | 3 of 14 |
| microcrystalline cellulose | 3 of 14 |
| sunflower lecithin | 3 of 14 |
| beeswax | 2 of 14 |
| citric acid | 2 of 14 |
7 additional rows
| Filed entry | Labels |
|---|---|
| Adult (18 - 50 Years) | 14 of 14 |
| Gluten Free | 14 of 14 |
| Dairy Free | 14 of 14 |
| Kosher | 11 of 14 |
| Vegan | 10 of 14 |
| Vegetarian | 10 of 14 |
| Halal | 5 of 14 |
Source · NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which NOW labels are on file, and what does each declare?
NOW has 14 on-market labels in the NIH DSLD snapshot 2026-08-10, with a median declared amount of 400 mg of elemental magnesium per serving; each row opens the label's own arithmetic.
measured| Label | Declared per serving | Salt | Capsule verdict |
|---|---|---|---|
| NOW Magnesium & Calcium | 800 mg | not resolved | not computable |
| NOW Magnesium & Calcium | 800 mg | not resolved | not computable |
| NOW Magnesium & Potassium Aspartate | 250 mg | aspartate | needs 000 |
| NOW Magnesium Bisglycinate Powder | 250 mg | glycinate | not applicable |
| NOW Magnesium Caps 400 mg | 400 mg | not resolved | not computable |
| NOW Magnesium Citrate | 400 mg | citrate | needs 000 |
| NOW Magnesium Citrate | 400 mg | citrate | needs 000 |
| NOW Magnesium Citrate 400 mg | 400 mg | citrate | needs 000 |
6 additional rows
| Label | Declared per serving | Salt | Capsule verdict |
|---|---|---|---|
| NOW Magnesium Citrate Softgels | 400 mg | citrate | not applicable |
| NOW Magnesium Citrate Softgels | 400 mg | not resolved | not computable |
| NOW Magnesium Glycinate | 200 mg | glycinate | not applicable |
| NOW Magnesium Malate Caps | 95 mg | malate | needs 00 |
| NOW Magnesium Oxide Pure Powder | 290 mg | oxide | not applicable |
| NOW Magnesium Transporters | 120 mg | not resolved | not computable |
Source · NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does NOW share a filed formulation with other brands?
1 filed formulation of NOW also appears under other brands, matched by ingredients, shell, units and rounded amount; within one salt their observed prices differ by up to ×1.0.
computed| Formulation | Labels | Brands |
|---|---|---|
| 135 mg × 3 · beeswax, bovine gelatin, glycerin… | 2 | 2 |
Source · NIH DSLD labels · snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method