In answering the question is Magnesium Stearate good or bad, I would say that it can definitely be bad for you... if you drop a 25 kilogram pail of it on the floor in a small room and inhale it, or you drown in it.
Seriously though, it is always easier to believe something rooted in fear rather than fact, regardless of how inaccurate it may be.
Take the tomato, for example, considered poisonous for over two hundred years in Europe, due to early inaccurate writings, and its tendency to absorb lead from pewter bowls. (1) Or how about cholesterol and saturated fat causing heart attacks? Fears that have been capitalized upon by the pharmaceutical and food industries for the better part of a century. Yet they're not true, and are being exposed. (2)
Why do such myths persist?
Because of graphic descriptions that effectively create images in the public mind that seem to make sense, yet are based on faulty evidence presented out of context.
Images like fatty deposits being pulled out of the arteries of rabbits fed cholesterol, when rabbits don't eat cholesterol! Hence, they are not set up to metabolize it, and the models are not indicative of what happens in humans! (But images like this have scared millions into taking cholesterol-lowering drugs!)
Such is the case with Magnesium Stearate which has been said to inhibit immune (T-cell) function, and cause the membranes in T-helper cells to collapse. So this sounds pretty sinister! But hold on...
Taking a deeper look, this was ONE 1990 study in mice! But no, it was actually a study of mouse cells in a petri dish that were "bathed", i.e. drenched in a solution of magnesium stearate.
(See reference link below)
So, does this compare to the cells of humans that have swallowed milligram amounts of magnesium stearate the size of the tip of ballpoint pen? Or is it closer to the cells of a human that has drown in a pool of magnesium stearate? (A huge difference!) And further, because mice lack the enzyme to convert stearic acid into oleic acid...i.e. the fat found in olive oil.....but humans have this enzyme, stearic acid/stearate can be toxic for mouse cells, but good for humans!
So here is a more suitable way to state the situation
Because when magnesium stearate hits the acidic environment of your stomach, it separates into one magnesium...arguably the body's most crucial mineral.... and two molecules of stearic acid, which then converts into oleic acid, predominant in the Mediterranean diet, which favourably affects blood lipid profiles...magnesium stearate is good for you!
Of course, this is going to the opposite extreme. But it is closer to the truth then the original claim, which was totally distorted and pulled out of context in articles published by Dr. Mercola, among others.
As I stated in our previous article on the subject....see link: Is Magnesium Stearate in Supplements As Big a Deal As Dr. Mercola Is Making It Out To Be?...I like Dr. Mercola, and think his website is an extremely valuable source of natural health information. But there are some times when he gets off on tangents that are best described in one word..."BASELESS"!
The same conclusions have been reached by many other respected natural health/ nutrition professionals, whose sites are listed at the bottom of this article.
This includes Dr. Steven Levine PhD. from Allergy Research Group (ARG) who was one of the founders in the field of formulating hypoallergenic supplements for sensitive people. In this ARG Focus interview with Dr. Dana Myatt, she systematically discredits all the arguments supporting the idea that magnesium stearate is "potentially hazardous" as Dr. Mercola describes. She does such a good job that I couldn't say it any better, so read the interview, or listen to the YouTube video linked in the first paragraph! It's excellent.
Magnesium Stearate - The Truth about Magnesium Stearate
Hence, if you are avoiding magnesium stearate strictly based on Dr. Mercola's advice, then perhaps think again.
In the end, the truth usually varies from one individual to another, and its the result that counts. If you actually notice that you seem to have a bad response to magnesium stearate, then act on it, and avoid it. But, in consulting thousands of people on supplements since 1986 I have only talked to two individuals, with particularly sensitive G.I. tracts, that specifically thought they reacted to it. Yet, they avoided capsules, tablets, and all binders and fillers too, so who knows what they were reacting to?
A person may instead be having immune responses to some other non-medicinal ingredients that Dr. Mercola uses in his supplements, (all of which I have also known sensitive people to have said reactions to...taken directly from his site).
Sucrose, Maltodextrin, Polyglycerol Oleate, Beeswax, Metolose, Calcium Laurate, Tilapia Fish Gelatin, Pea Protein, Fructooligosaccharide, Guar Gum, Gellan Gum, Potassium Sorbate, Xanthan Gum, Citric Acid, Paprika oleoresin [paprika is a nightshade]
Continue to be well!