Label arithmetic · NIH DSLD 244068
Biotech Nutritions Magnesium Citrate: 225 mg of magnesium per capsule, 1 capsule a day
225 mg of magnesium per capsule takes 1,392–1,991 mg of citrate; size 000 holds about 1,100 mg (model). Inside: salt weight, capsule size.
Estimated salt mass versus assumed capsule capacity: Biotech Nutritions Magnesium Citrate implies 1,392–1,991 mg of magnesium citrate per capsule from 225 mg elemental magnesium per serving, above the assumed 1,100 mg capacity of size 000 at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range, calculated 2026-11-02. No US retail price matched as of 2026-11-02; 17 of the 135 citrate labels in this registry have a matched price. NIH DSLD 244068, label dated 2021-02-25.
computed from the filed label
Chart data
| Displayed chart text |
|---|
| 545 mg |
| 730 mg |
| 1,100 mg |
| 1,392–1,991 mg of citrate per capsule |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-10-19 · chemistry 2026-10-17
Mass: 1,392–1,991 mg per capsule · Price: none matched · % DV: 54% vs 54%
Elemental: The magnesium itself; the rest of the compound weight is the partner molecule.
Compound: The whole salt, such as magnesium glycinate, that must physically fit in the capsule.
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; size 00 holds about 730 mg and size 0 about 545 mg.
Recompute with your price
Enter the price you paid; the declared amount and servings of this label are prefilled, so the result is the cost per 100 mg of elemental magnesium for your bottle.
Same-salt comparison appears here.
Estimated salt mass versus assumed capsule capacity
Estimated salt mass versus assumed capsule capacity: Biotech Nutritions Magnesium Citrate implies 1,392–1,991 mg of magnesium citrate in each capsule to deliver 225 mg of elemental magnesium, against 1,100 mg in the largest standard capsule (size 000) at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range. Verdict: exceeds size 000, read at the most favourable hydration and the most units per serving.
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | 225 mg |
| Units per serving | 1 |
| Magnesium citrate per serving | 1,392–1,991 mg |
| Magnesium citrate per capsule | 1,392–1,991 mg |
| Capsule capacity 0 · 00 · 000 | 545 · 730 · 1,100 mg |
| Verdict | Exceeds size 000 |
The filed salt can have more than one hydration state (trimagnesium dicitrate 16.2%; dibasic and hydrated forms as low as 11.3%), so the compound mass is a range.
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
Biotech Nutritions Magnesium Citrate files 1 magnesium line in NIH DSLD 244068; the selected primary line declares 225 mg of elemental magnesium per serving, against 0 other rows excluded from the primary amount. A salt named under another nutrient does not turn that nutrient's quantity into elemental magnesium.
measured| Filed amount | Salt or note as filed | Role |
|---|---|---|
| 225 mg | citrate · Magnesium (Form: as Magnesium Citrate) | Primary serving |
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's citrate claim hold up, or could the magnesium come from another source?
For this declaration to fit one size 000 capsule, at least 29% of the magnesium would have to come from a salt richer in magnesium, such as magnesium oxide (computed at powder density 0.8 g/mL, the top of the usual 0.6–0.8 range), compared with oxide, the salt richest in magnesium at 60.3%.
computed with assumption| Form named on the label | Elemental fraction | Source |
|---|---|---|
| Magnesium citrate | 11.3–16.2% | filed magnesium line |
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Is this a good price for the elemental magnesium I'm actually getting?
No US retail price is matched to this label as of 2026-11-02; 17 of 135 citrate labels have one, against a median of $0.1159 per 100 mg among 12 ranked citrate offers.
computed
Chart data
| Displayed chart text |
|---|
| n=12 |
| P25 $0.0843 |
| P75 $0.1469 |
| median $0.1159 |
| Rank | Label | Per 100 mg | Observed |
|---|---|---|---|
| 1 | Best Naturals Magnesium Citrate 200 mg | $0.0344 | 2026-11-02 |
| 2 | Solgar Magnesium Citrate | $0.0607 | 2026-11-02 |
| 3 | LES Labs Magnesium Citrate | $0.0777 | 2026-11-02 |
| 4 | Bluebonnet Magnesium Citrate | $0.0865 | 2026-11-02 |
| 5 | Solaray Magnesium Citrate 400 mg | $0.0868 | 2026-11-02 |
| Median | 12 ranked citrate offers | $0.1159 | 2026-11-02 |
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
How many days will this bottle last at the label's own serving, and what does a day cost?
At the label's own serving, Biotech Nutritions Magnesium Citrate lasts 120 days: 120 servings against 1 serving a day in the filed directions.
computed| Measure | Value |
|---|---|
| Net contents as filed | 120 Capsule(s) |
| Serving size as filed | 1 Capsule(s) |
| Servings per container | 120 |
| Servings per day in the directions | 1 |
| Days per bottle | 120 days |
| $ per 30 days at one label serving a day | No ranked price as of 2026-11-02 |
| $ per 30 days at 420 mg Daily Value | No ranked price as of 2026-11-02 |
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "54% Daily Value" mean here, and does it recompute?
The label declares 54% Daily Value; 225 mg against the 420 mg reference in 21 CFR 101.9 recomputes to 54%, the same within one point.
computed| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 54% | 420 mg | 54% |
Source · NIH DSLD 244068; 21 CFR 101.9 · label 2021-02-25 · release 2026-08-10-f441aa9f · CSV · method
Why does this label contain these other ingredients, what shell is it, and who is it filed for?
Biotech Nutritions Magnesium Citrate files 1 other ingredient and a vegetarian shell, and no magnesium stearate, against 43 of 135 citrate labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Vegetable Capsule |
| Shell | vegetarian |
| Target group | Adult (18 - 50 Years) |
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about citrate, and about side effects?
10 studies in the PubMed-checked registry measured outcomes involving citrate; 1 mention gastrointestinal or adverse outcomes. They measured the salt, not this label.
measured| Year | Study | PubMed |
|---|---|---|
| 2025 | Comparing the Bioavailability of Two Seawater-Derived Magnesium Preparations. | 40955524 |
| 2024 | Comparative Clinical Study on Magnesium Absorption and Side Effects After Oral Intake of Microencapsulated Magnesium (MAGSHAPE™ Microcapsules) Versus Other Magnesium Sources. | 39770988 |
| 2022 | Effects of short-term magnesium supplementation on ionized, total magnesium and other relevant electrolytes levels. | 35041150 |
Source · PubMed-checked study registry · registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Has this brand had FDA recalls or adverse event reports?
Biotech Nutritions has 0 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. Biotech Nutritions has no FDA CAERS adverse event report on record at brand level as of 2026-10-19 (143 of 273 brands in this registry have at least one CAERS report).
measured| Recall | Date | Reason | Status |
|---|---|---|---|
| No recall record as of 2026-10-19 |
Source · openFDA enforcement and CAERS · queried 2026-10-19 · release 2026-08-10-f441aa9f · CSV · method
Is this the same formula as another brand's, and how do their prices differ?
No other brand files the same formulation (ingredients, shell, units and rounded amount) as of 2026-11-02.
computed| Label | Brand | Price per 100 mg |
|---|---|---|
| No cross-brand match as of 2026-11-02 |
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which labels are closest to this one, with the same salt and dose?
6 labels use the same resolved citrate within ±10% of this label's 225 mg per unit, compared side by side on price and capsule verdict.
computed| Label | Elemental per unit | Price | Verdict |
|---|---|---|---|
| Swanson Magnesium Citrate 225 mg Super Strength | 225 mg | No price | Capsule sizes do not apply |
| Solgar Magnesium Citrate (DSLD 219453) | 210 mg | $15.29 · 2026-11-02 | Capsule sizes do not apply |
| Solgar Magnesium Citrate (DSLD 219466) | 210 mg | $15.29 · 2026-11-02 | Capsule sizes do not apply |
| Solgar Magnesium Citrate (DSLD 241135) | 210 mg | $15.29 · 2026-11-02 | Capsule sizes do not apply |
| Solgar Magnesium Citrate (DSLD 241141) | 210 mg | No price | Capsule sizes do not apply |
| Solgar Magnesium Citrate (DSLD 241142) | 210 mg | No price | Capsule sizes do not apply |
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Where does this record come from, what is missing, and how do I cite or correct it?
Every value on this page traces to NIH DSLD 244068 (label 2021-02-25, snapshot 2026-08-10) and the chemistry model of 2026-09-13. 1 gap remain: No US retail price matched as of 2026-11-02 (barcode 6 16983 00255 1). The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 244068 |
| Label date | 2021-02-25 |
| Date entered into DSLD | 2021-02-25 |
| Barcode (UPC) as filed | 6 16983 00255 1 |
| Manufacturer | Biotech Nutritions, Novi, MI |
| Claim category as filed | All Other |
| Claim category as filed | Structure/Function |
| Suggested/Recommended/Usage/Directions | Suggested use: (Adults only) As a dietary supplement, take two (2) capsules per day with a glass of water. |
11 additional rows
| Field | As filed |
|---|---|
| Precautions re: All Other | Caution: Do not exceed recommended dose. |
| Precautions re: Children | Pregnant or nursing mothers, children under 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement. |
| Precautions re: Pregnant or Nursing or Prescription Medications | Pregnant or nursing mothers, children under 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement. |
| FDA Disclaimer Statement | These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. |
| Precautions re: Children | Keep out of the reach of children. |
| Precautions re: All Other | Do not use if safety seal is damaged or missing. |
| General Statements: All Other Content | Order online: www.BiotechNutrtions.com |
| Seals/Symbols | Made in USA |
| FDA Statement of Identity | Dietary Supplement |
| Physical state | Capsule |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 244068 · label 2021-02-25; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
6 brand pages linked below contain magnesium labels from the NIH DSLD registry snapshot dated 2026-08-10.