World Health Officials Question Safety of Magnesium Stearate
Source: 05 December 2012 | thorne.com/practitioners/resources/articles/world-health-officials-question-safety-magnesium-stearate
The Joint Food and Agriculture Organization of the United Nations and the World Health Organization (FAO/WHO) Expert Committee on Food Additives (JECFA) have recently made the determination to investigate whether or not the use of magnesium stearate is safe. JECFA, as part of the international Codex Alimentarius Commission's effort to harmonize the food and supplement regulations of member countries, is evaluating data on food additives, and it has found some gaps in the existing data on magnesium stearate.
Magnesium stearate is the most commonly used excipient in the manufacturing of pharmaceuticals and dietary supplements. Magnesium stearate in powder form is used as a flowing agent – when it is added to another powder magnesium stearate changes the physical characteristics of the combined powder such that it flows easier. This makes the manufacturing process of pharmaceuticals and dietary supplements much more efficient – and less costly.
Although magnesium stearate has been widely used for decades, there is only minimal data to support its safety and toxicology. Thorne Research is not saying magnesium stearate is unsafe; however, without adequate toxicology and safety data, pharmaceutical and dietary supplement manufacturers doing business in Europe might be forced to stop using it if JECFA takes action against it.
During its entire existence of 28 years, Thorne Research has manufactured the highest quality dietary supplements WITHOUT using magnesium stearate. Not because it is unsafe, but because it is unnecessary, AND, because magnesium stearate can significantly affect the physical characteristics of any powdered nutrient to which it is added.
For a manufacturer, the addition of magnesium stearate is a good thing, because it makes their production processes that much more efficient. However, Thorne Research has determined that adding even a small amount of magnesium stearate (as little as one percent) can significantly decrease nutrient dissolution.
What does this mean? A powder that is 99-percent nutrient content and one-percent magnesium stearate content has a much lower propensity to dissolve in solution than does a 100-percent nutrient content of that same powder without magnesium stearate.
In one unpublished study, the addition of only one-percent magnesium stearate to pure ascorbic acid powder reduced the dissolution of the combined powdered mixture at one hour's time by 65 percent (see the chart below). Can this affect absorption in the body? Thorne Research believes that it does. At the very least, we believe it makes absorption of the nutrient unpredictable.
Notwithstanding the recent JECFA admission on magnesium stearate's safety profile, Thorne Research's position on magnesium stearate will remain what it has always been: it is an unnecessary additive and it offers no benefit whatsoever to the patient.
Using magnesium stearate simply makes it easier for the manufacturer to make the product. Thorne Research has been manufacturing its dietary supplements for 28 years without using magnesium stearate. Whatever action JECFA might take regarding magnesium stearate, JECFA's action will have no impact on Thorne Research because Thorne Research has never used magnesium stearate – and we never will.