Magnesium Stearate: Here’s why it’s not harmful



What is magnesium stearate?


Magnesium stearate is a type of magnesium salt of stearic acid which, at room temperature, is a white, odourless and water-insoluble powder. Stearic acid is a saturated fatty acid found in many foods, including animal and vegetable fats and oils. Cocoa and flaxseed, for example, are foods that contain significant amounts of stearic acid. It is important to remember that this substance should not be considered as a magnesium supplement, as it contains a very small percentage of the mineral. On the label, its presence may be declared as "magnesium stearate", "magnesium salts of fatty acids" or under the acronym E470b.


What is the purpose of magnesium stearate?


It is widely used in the cosmetics, pharmaceutical and food industries as an anti-caking agent, emulsifier and lubricant. It speeds up the production process by preventing ingredients from sticking to the mechanical equipment, facilitating and improving powder processing. In addition to accelerating production, magnesium stearate gives capsules and tablets more consistency, making them easier to swallow and to move along the gastrointestinal tract.


What are the health risks of magnesium stearate?


The FDA (Food and Drug Administration) in the United States has approved the use of magnesium stearate as an additive in foods and supplements. This excipient is also included in the list of food additives authorised in Italy in accordance with the directives of Regulation (EC) No 1333/2008. In its database, Altroconsumo (a consumer organisation), classifies the use of this additive as "acceptable" in certain specific cases, specifying that there is no associated effect on the organism as far as we know it (neither beneficial nor harmful).


According to the National Centre for Biotechnology Information, it is generally recognized as a safe substance when consumed in quantities of less than 2,500 milligrams (mg) per kilogram per day. This means, for example, that a male adult weighing 85 kg could take up to 212,500 mg per day, the equivalent of about 283,750 mg of capsules per day. It therefore does not appear to have any side effect or harmful consequences if taken in small quantities, such as those used by capsule and drug manufacturers.


True or false?


1. There is no scientific evidence to suggest that magnesium stearate can suppress the functions of T lymphocytes, which are highly specialized cells that fight intracellular pathogens, such as viruses and some bacteria. This belief is based on a 1990 study conducted on a single mouse. When the mouse T cells were incubated with stearic acid (not magnesium stearate), the cell membrane collapsed and the T cells lost all function. However, this experiment - and therefore also its results - cannot be replicated with human beings because the T cells of mice do not possess a specific enzyme (called stearoil-CoA 9-desaturase), which is available in human beings, capable of converting stearic acid into oleic acid and thus cancelling the alleged toxicity of this substance.


2. Nor is there any scientific evidence to support claims that magnesium stearate could affect the body's ability to absorb the contents of drug capsules. Studies conducted so far on this substance show that absorption of the active ingredients could be slowed down, but not compromised (10, 11).


3. Another concern is the possible contamination of magnesium stearate, which, often obtained from cottonseed oil, may have pesticides or come from GMOs. Nevertheless, this substance is highly purified by an intensive refining process before being incorporated as an ingredient in foods, cosmetics and supplements. In addition, the final molecular form of magnesium stearate is identical, whether it comes from a GMO cotton plant or a non-GMO plant.


So why did we choose to remove it from our supplements?


Despite the safety of this additive in small amounts, one should remember that magnesium stearate is not a natural substance.


Our philosophy, in addition to guaranteeing high quality products, is to create supplements as natural as possible, avoiding the use of artificial additives. That is why we are gradually eliminating magnesium stearate from our products, replacing it with other natural additives that, together, mimic the function of the excipient. These natural additives, of course, are only added when they are needed.


The natural additives we use are mainly:


  - Rice bran extract (EBR) and sunflower oil


They are used as stabilizers in some supplements when it is necessary to increase the ability of ingredients to bind together. In addition, it is possible to obtain an organic version of these natural additives, which can therefore also be used in our organic supplements.


Before using the rice bran extract, we used microcrystalline cellulose (E460i), a vegetable-based cellulose with stabilizing and gelling properties. However, high consumption of this additive, which is not absorbed in the intestine, can increase the frequency and volume of intestinal movements; but also raise the number of intestinal losses and cause meteorites or diarrhoea. For this reason, it is prohibited in Australia. In addition, the European Food Safety Authority (EFSA) has not approved any claims certifying the benefits of the use of this substance.


- Gum arabic or acacia gum (E414)


It is used as a binder as well. In accordance with the regulations of the Ministry of Health, there are no restrictions on the maximum amount that can be used.


- Hydroxypropylmethylcellulose (E464)


As a coating agent, i.e. as a packaging material for our capsules, we use hydroxypropylmethylcellulose (E464), which is commonly used as a food additive because of its stabilizing and thickening properties. This excipient is a cellulose derivative and is extracted directly from natural strains of vegetable fibres. ESFA has approved two beneficial properties derived from two hypothesis of this type of cellulose. The first is that - if taken in a minimum quantity of 4 grams - it can help reduce the glycemic response after meals, by helping to reduce the increase in blood sugar. The second, on the other hand, certifies the usefulness of hydroxypropylmethylcellulose in maintaining blood cholesterol levels at normal rates. However, this claim may only be used for products that provide a daily dosis of 5 grams of hydroxypropylmethylcellulose.


How do I know if a supplement is of good quality?


When it is as natural as possible and therefore does not hold any artificial or unnecessary additives. We advise to always read the labels carefully. Indeed, companies are still required to declare all the ingredients included, excipients cannot be excluded from the list. If the labels are not clearly visible and readable, especially on the Internet, or if the list of ingredients is missing, consider it questionable.


When manufacturers use high quality raw materials, certified and periodically tested by independent third-party laboratories to verify that contamination levels are in compliance with the standard.


When it complies with industry standards for guaranteed quality, including ISO 9001, ISO 17025 and Good Manufacturing Practices (GMP).



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