Label arithmetic · NIH DSLD 56862
Douglas Laboratories Magnesium Citrate
Douglas Laboratories Magnesium Citrate declares 150 mg of elemental magnesium as citrate, which needs 928–1,327 mg of salt per unit — a size 000 capsule or larger; NIH DSLD 56862, label dated 2016-02-23, calculation 2026-09-13.
FDA recall records for Douglas Laboratories: 1 · queried 2026-09-13; brand-string matches across products.
Mass budget · computed; capsule comparison · modelled
What the declared salt would weigh
Douglas Laboratories Magnesium Citrate declares 150 mg of elemental magnesium per serving in NIH DSLD 56862, requiring 928.22–1,327.43 mg of magnesium citrate under the salt model calculated 2026-09-13.
| Step | Value | Evidence |
|---|---|---|
| Declared elemental magnesium | 150 mg per serving | observed · label 2016-02-23 |
| Resolved salt | Magnesium citrate · label-row | computed · name resolved from filed text |
| Reference formula | Mg₃(C₆H₅O₇)₂; 451.11 g/mol | computed · chemical reference |
| Elemental fraction | 11.3–16.16% by mass | computed |
| Why the fraction is a range | trimagnesium dicitrate 16.2%; dibasic and hydrated forms as low as 11.3% | modelled · hydrate not specified |
| Compound mass per serving | 928.22–1,327.43 mg = 150 mg ÷ elemental fraction | computed |
| Compound mass per discrete unit | 928.22–1,327.43 mg | computed |
At powder density 0.6–0.8 g/mL, 928 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
Douglas Laboratories Magnesium Citrate has 11 published fields below, traced to NIH DSLD 56862 and the 2026-08-10 registry snapshot, with calculations dated 2026-09-13.
| Field | Value | Evidence tier |
|---|---|---|
| NIH DSLD identifier | 56862 | observed |
| Resolved salt | Magnesium citrate | computed |
| Source of the resolved salt | label-row | observed |
| Elemental magnesium per serving (mg) | 150 | observed |
| Servings per container | 90 | observed |
| Elemental magnesium per container (mg) | 13500 | computed |
| Compound mass per discrete unit | 928.22–1,327.43 mg | computed |
| Capsule fill verdict | needs-000 | modelled |
| Required standard capsule size | 000 | modelled |
| Label date | 2016-02-23 | 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
Douglas Laboratories Magnesium Citrate retains 1 magnesium-related rows in NIH DSLD 56862, including 1 rows selected for the primary serving, from label 2016-02-23, examined 2026-09-13.
| Filed amount | Serving order | Filed salt / notes | Calculation role |
|---|---|---|---|
| 150 mg | 1 | citrate Magnesium (Form: from Magnesium Citrate) | 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
Douglas Laboratories Magnesium Citrate works out to 90 days per package at the label's own serving and filed frequency of 1 servings per day, according to label 2016-02-23, calculated 2026-09-13.
| Net contents as filed | 90 Capsule(s) |
|---|---|
| Discrete units in the package | 90 |
| Serving size as filed | 1 Capsule(s) |
| Units per serving | 1 |
| Servings per package | 90 |
| Daily servings in the label instructions | 1 |
| Days per package at the label's own serving | 90 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.
Benchmark · 19 observed prices in citrate
A same-salt reference for this package
At the median cost per 100 mg observed across 19 citrate labels ($0.1039), a package of this size (13,500 mg elemental in Douglas Laboratories Magnesium Citrate) would correspond to $14.03, using observations from 2026-08-10 to 2026-09-11, calculated 2026-09-13. This is a benchmark, not a retailer quote.
| Salt and number of observations | Magnesium citrate · n = 19 |
|---|---|
| Median observed cost per 100 mg | $0.1039 |
| Filed elemental magnesium per package | 13,500 mg |
| Benchmark package equivalent | $14.03 = median EC100 × package elemental mg ÷ 100 |
| Evidence tier | benchmark · calculated 2026-09-13 |
The median is the middle sorted observation, or the average of the two middle observations for an even group. Each label contributes one observation. This value is neither an offer nor an estimate of a specific retailer's current price.
Percent daily value · observed and computed
The label's percent daily value, recomputed
Douglas Laboratories Magnesium Citrate files 1 magnesium percent-daily-value entries in NIH DSLD 56862; the check below applies the group-specific references in 21 CFR 101.9 to its 150 mg primary serving, calculated 2026-09-13.
| Group as filed | Declared | Reference | Recomputed | Difference |
|---|---|---|---|---|
| Adults and children 4 or more years of age | 38% | 420 mg | 36% | 2 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
Douglas Laboratories Magnesium Citrate lists 3 other ingredients in NIH DSLD 56862, label dated 2016-02-23, examined 2026-09-13.
| Entry | Ingredient |
|---|---|
| 1 | Cellulose |
| 2 | Gelatin |
| 3 | Vegetable Stearate |
Capsule material: gelatin. The material classification follows the filed ingredient names; it is not a test of the shell.
Label declarations · observed
Target groups as filed
Douglas Laboratories Magnesium Citrate has 4 target-group entries in NIH DSLD 56862, label dated 2016-02-23, examined 2026-09-13.
| Entry | Filed group |
|---|---|
| 1 | Adult (18 - 50 Years) |
| 2 | Gluten Free |
| 3 | Dairy Free |
| 4 | Sugar Free |
Provenance · observed
Registry record, versions and scanned label
The registry holds 5 versions of this label for Douglas Laboratories Magnesium Citrate, according to the retained record examined 2026-09-13; the label date is 2016-02-23.
| NIH DSLD label | NIH DSLD 56862 |
|---|---|
| Registry snapshot | 2026-08-10 |
| Label date | 2016-02-23 |
| Physical state | Capsule |
| Barcode as filed | 3 10539 00337 4 |
| 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
Douglas Laboratories Magnesium Citrate 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 56862 (barcode 3 10539 00337 4) 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.