Label arithmetic · NIH DSLD 204986
NOW Magnesium & Potassium Aspartate
NOW Magnesium & Potassium Aspartate declares 250 mg of elemental magnesium per serving as aspartate, which would require 1,485 mg of the salt in each unit — more than the 1,100 mg a size 000 capsule holds; NIH DSLD 204986, label dated 2019-07-24, calculation 2026-09-13.
FDA recall records for NOW: 1 · queried 2026-09-13; brand-string matches across products.
Mass budget · computed; capsule comparison · modelled
What the declared salt would weigh
NOW Magnesium & Potassium Aspartate declares 250 mg of elemental magnesium per serving in NIH DSLD 204986, requiring 2,969.12 mg of magnesium aspartate under the salt model calculated 2026-09-13.
| Step | Value | Evidence |
|---|---|---|
| Declared elemental magnesium | 250 mg per serving | observed · label 2019-07-24 |
| Resolved salt | Magnesium aspartate · label-row | computed · name resolved from filed text |
| Reference formula | Mg(C₄H₆NO₄)₂; 288.5 g/mol | computed · chemical reference |
| Elemental fraction | 8.42% by mass | computed |
| Compound mass per serving | 2,969.12 mg = 250 mg ÷ elemental fraction | computed |
| Compound mass per discrete unit | 1,484.56 mg | computed |
At powder density 0.6–0.8 g/mL, 1,485 mg of powder exceeds every standard capsule size — the largest, 000, holds about 1,100 mg.
If the declared salt were the sole source of magnesium here, each capsule would need 1,485 mg of powder, which no standard capsule holds. So the label does not establish aspartate as the only source. A blend with a denser salt or a non-standard capsule could reconcile it. This is a statement about the label's arithmetic, not about what is in the bottle.
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
NOW Magnesium & Potassium Aspartate has 11 published fields below, traced to NIH DSLD 204986 and the 2026-08-10 registry snapshot, with calculations dated 2026-09-13.
| Field | Value | Evidence tier |
|---|---|---|
| NIH DSLD identifier | 204986 | observed |
| Resolved salt | Magnesium aspartate | computed |
| Source of the resolved salt | label-row | observed |
| Elemental magnesium per serving (mg) | 250 | observed |
| Servings per container | 60 | observed |
| Elemental magnesium per container (mg) | 15000 | computed |
| Compound mass per discrete unit | 1,484.56 mg | computed |
| Capsule fill verdict | exceeds-all | modelled |
| Required standard capsule size | No standard size fits as of 2026-09-13 | modelled |
| Label date | 2019-07-24 | observed |
| Retail match confidence | unmatched | computed |
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
NOW Magnesium & Potassium Aspartate retains 1 magnesium-related rows in NIH DSLD 204986, including 1 rows selected for the primary serving, from label 2019-07-24, examined 2026-09-13.
| Filed amount | Serving order | Filed salt / notes | Calculation role |
|---|---|---|---|
| 250 mg | 1 | aspartate Magnesium (Form: from Magnesium Aspartate) | 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
NOW Magnesium & Potassium Aspartate works out to 30–60 days per package at the label's own serving and filed frequency of 1–2 servings per day, according to label 2019-07-24, calculated 2026-09-13.
| Net contents as filed | 120 Veg Capsule(s) |
|---|---|
| Discrete units in the package | 120 |
| Serving size as filed | 2 Veg Capsule(s) |
| Units per serving | 2 |
| Servings per package | 60 |
| Daily servings in the label instructions | 1–2 |
| Days per package at the label's own serving | 30–60 days |
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
NOW Magnesium & Potassium Aspartate files 1 magnesium percent-daily-value entries in NIH DSLD 204986; the check below applies the group-specific references in 21 CFR 101.9 to its 250 mg primary serving, calculated 2026-09-13.
| Group as filed | Declared | Reference | Recomputed | Difference |
|---|---|---|---|---|
| Adults and children 4 or more years of age | 60% | 420 mg | 60% | 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
NOW Magnesium & Potassium Aspartate lists 4 other ingredients in NIH DSLD 204986, label dated 2019-07-24, examined 2026-09-13.
| Entry | Ingredient |
|---|---|
| 1 | Hypromellose |
| 2 | Rice Flour |
| 3 | Stearic Acid |
| 4 | Silicon Dioxide |
Capsule material: vegetarian. The material classification follows the filed ingredient names; it is not a test of the shell.
Label declarations · observed
Target groups as filed
NOW Magnesium & Potassium Aspartate has 6 target-group entries in NIH DSLD 204986, label dated 2019-07-24, examined 2026-09-13.
| Entry | Filed group |
|---|---|
| 1 | Vegan |
| 2 | Vegetarian |
| 3 | Adult (18 - 50 Years) |
| 4 | Kosher |
| 5 | Gluten Free |
| 6 | Dairy Free |
Provenance · observed
Registry record, versions and scanned label
The registry holds 5 versions of this label for NOW Magnesium & Potassium Aspartate, according to the retained record examined 2026-09-13; the label date is 2019-07-24.
| NIH DSLD label | NIH DSLD 204986 |
|---|---|
| Registry snapshot | 2026-08-10 |
| Label date | 2019-07-24 |
| Physical state | Capsule |
| Barcode as filed | 7 33739 01320 0 |
| Versions held by the registry | 5; version details are not available in this enrichment record as of 2026-09-13 |
| Calculation date | 2026-09-13 |
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
NOW Magnesium & Potassium Aspartate has 1 unresolved data gaps in the retained NIH DSLD and price records as of 2026-09-13.
| Entry | Known gap |
|---|---|
| 1 | No confirmed US retail price matched to NIH DSLD 204986 (barcode 7 33739 01320 0) 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.