The Short Answer: Yes, magnesium stearate is safe. It is safe enough that it was granted generally recognized as safe (GRAS) status in the USA by the FDA. It is also permitted for use in the European Union and other countries including Japan, Australia and New Zealand. The World Health Organization has also confirmed the safety of magnesium stearate.We have extensively investigated the safety of magnesium stearate and there is no scientific evidence we have been able to find to substantiate any claims that it has any harmful effects in the miniscule amounts that are in dietary supplements.The Long Answer: Any magnesium stearate used in our supplements is derived from vegetable oil and helps with the encapsulation process.It is a combination of stearic acid and the essential mineral magnesium. Each Respire capsule contains a tiny amount of stearic acid (less than 10 mg). For the sake of comparison a half of a bar of chocolate (about 112 calories) contains over 1200mg of stearic acid.Consumerlabs reported that a survey conducted by the USDA indicates the average American adult consumes 5,900 - 8,800mg daily of stearic acid from food sources including beef, poultry, cocoa butter, milk and cheese. Allegations of its toxicity have been circulating for decades. However the “evidence” appears to be misleading because it is either largely circumstantial based on test tube studies that don't accurately represent the data observed in human trials or based on theoretical dangers (such as a type of processing that is not commonly used to make stearic acid from unsaturated fats) that don’t apply to the materials we use. Either way, the fate of dietary fats in the human body is quite different than what these theories present.It is safe to say that too much of anything may not be good for you and while it may not be desirable to consume several ounces per magnesium stearate, there does not appear to be any credible basis for the accusations made by certain "experts" when it comes to the use of the miniscule amounts of the ingredient in dietary supplements.