What is Magnesium Stearate (Magnesium Stearate · Lubricant / Anti-adherent)?
Magnesium stearate is the magnesium salt of stearic acid (a saturated fatty acid); it is a white, hydrophobic powder. It is not used as a nutritional mineral but as a flow agent and lubricant excipient in tablet and capsule production. It is the most common lubricant in solid dosage forms (%0.25–5).
- Molecular formula: C₃₆H₇₀MgO₄
- CAS number: 557-04-0
- Magnesium stearate (CAS 557-04-0) contains only ~%4 elemental Mg by weight; however, its function is NOT as a magnesium source, but as a production aid (lubricant). It is used in the range of a few mg per tablet; the magnesium it provides is negligible from a nutritional standpoint.
What Does Magnesium Stearate · Lubricant / Anti-adherent Do? Why is it Used?
Magnesium stearate is a reliable and cost-effective lubricant that improves powder flow, prevents sticking to equipment, and ensures consistent dose/weight in tablet/capsule production. Due to its hydrophobic structure, it can slow down disintegration/dissolution if used in excess, so it is added in the lowest effective amount (typically %0.25–1). The purpose is not nutritional supplementation, but manufacturability and product consistency.
Main areas of use: Tablet Compression, Capsule Filling, Dietary Supplements, Anti-foaming, Emulsifier, Food Industry, Pharmaceutical Production, High Purity.
Usage in Dietary Supplements
- Lubricant in tablet production: Prevents the powder mixture from sticking to molds and punches during tablet pressing, reduces friction, and ensures smooth ejection of the tablet from the mold.
- Flow agent in capsule filling: Ensures powder flow in capsule filling machines, helping to achieve consistent weight/dose filling; reduces caking.
- Anti-adherent: Prevents particles from sticking to equipment surfaces and to each other, keeping the equipment clean.
- Formulation process aid: Added not for nutritional value, but to facilitate the production process; present in trace amounts in the final product.
Usage in the Food Industry
- E470b additive: Used as an anti-caking agent, release agent, emulsifier, and stabilizer under the food additive code E470b (salts of fatty acids with magnesium).
- Quantum satis usage: Used in the lowest amount technologically necessary, according to the quantum satis principle in permitted categories.
- Areas of use: Used as a processing aid to prevent caking and ensure flow in powdered/tableted foods, confectionery, and supplements.
Effects on Health
Magnesium is a mineral that plays a role in many fundamental functions in the body. The main functions authorized/evaluated by the European Food Safety Authority (EFSA):
- Not a nutritional mineral: Magnesium stearate is a processing aid; it does not serve a nutritional function as a magnesium source. The trace magnesium does not make a significant contribution to daily requirements.
- Consumed in very small amounts: Ingested in the range of a few mg per tablet/capsule; it breaks down into stearic acid and magnesium and is generally safe and well-tolerated at these levels.
- Function is physical: Its effect arises not through metabolism like a nutrient, but through physical lubrication in production; EFSA magnesium claims are not referenced for this additive.
Usage Limits in Dietary Supplements
- Nutrient Reference Value (NRV): Not applicable — magnesium stearate is not considered a source of nutritional magnesium.
- Upper Intake Level (EFSA): Not applicable — EFSA's upper limit of 250 mg/day for supplemental magnesium applies to soluble magnesium supplements; trace magnesium in stearate is not evaluated in this context.
- Turkish legislation (TETGK): E470b is a permitted additive/processing aid in TR/EU; the usage amount is determined not by nutritional upper limits, but by technological necessity (quantum satis).
E470b is permitted on a quantum satis basis; the principle of 'the lowest amount technologically necessary' applies instead of a numerical daily upper limit — this is different from the NRV/UL framework for mineral supplements.
Technical Specifications
| Parameter | Value |
|---|---|
| Moisture | ≤5.0 % |
| Total Heavy Metals | ≤10 ppm |
| E. Coli | Negative in 10 g |
| Salmonella | Negative in 25 g |
| Solubility | Insoluble in Water |
Scientific Studies
The following independent researches relate to the bioavailability, use, and effects of this mineral (evidence levels are indicated):
- PubMed 23378252 — Study examining challenges in detecting magnesium stearate distribution in tablets.
- PubMed 35839984 — Study investigating the effect of alternative lubricants on process and tablet quality in direct compression.
Technical Documents and Supply — Asuka Kimya
You can contact Asuka Kimya for SDS, TDS, CoA and supply conditions for Magnesium Stearate.
References
- foodadditives.net
- ec.europa.eu
- ncbi.nlm.nih.gov
- dissolutiontech.com
- pubmed.ncbi.nlm.nih.gov
- pubmed.ncbi.nlm.nih.gov
The usage and health information on this page has been compiled from official legislation/institution sources (EFSA, NIH ODS, Turkish Food Codex, EUR-Lex) and independent scientific publications (PubMed). The product is a food supplement/food raw material; it does not aim to diagnose or treat diseases.