Magnesium Stearate and Silicon Dioxide: The Bad Guys of the Health Supplement World?

When it comes to choosing health supplements, most of us focus on the active ingredients, the vitamins, minerals, and herbs that promise better health and well-being. However, it’s important to take a closer look at the "inactive" ingredients listed on the label.

Among these, two names often stand out: magnesium stearate and silicon dioxide. Critics argue that these additives can have negative effects on health, but how much of this is true? Let’s dive into what these substances are, why they’re used, and whether or not they deserve their bad reputation.

What Are Magnesium Stearate and Silicon Dioxide?

Magnesium Stearate is a white, powdery substance made from magnesium and stearic acid, which is a fatty acid found in many foods like meat, eggs, chocolate, and some vegetables. It’s commonly used as a “flow agent” in supplements and medications. This means it helps ensure that the powder flows smoothly through the manufacturing machines, allowing for consistent dosing and preventing clumping.

Silicon Dioxide, also known as silica, is another commonly used flow agent and anti-caking agent. It’s naturally found in foods like leafy greens, grains, and even water. In supplement manufacturing, silicon dioxide helps prevent ingredients from sticking together, ensuring that capsules or tablets maintain their shape and consistency.

Both of these additives are considered "inert," meaning they don't have active effects in the body like the primary ingredients in a supplement. But their use has raised concerns among some consumers and health-conscious individuals.

The Arguments Against Magnesium Stearate

1. Potentially Inhibits Nutrient Absorption

One of the biggest criticisms of magnesium stearate is its alleged impact on nutrient absorption. Some sources claim that it forms a biofilm in the intestines, which might inhibit the absorption of certain nutrients. This has led to concerns that supplements containing magnesium stearate might be less effective.

However, there is limited scientific evidence to support this claim. A study published in the Journal of Pharmaceutical Sciences found that magnesium stearate, when used in reasonable quantities, does not significantly affect the dissolution of capsules and tablets . Most experts agree that in small amounts, magnesium stearate is unlikely to have a noticeable effect on nutrient absorption.

2. Possible Immune System Impact

Another argument is that stearic acid, a component of magnesium stearate, may suppress T-cell function, which is a critical part of the immune system. This claim is based on a 1990s study conducted on isolated cells, where stearic acid was shown to have some negative effects on T-cells. However, it’s important to note that the study used isolated T-cells and a direct application of stearic acid, not magnesium stearate as it is consumed in supplements.

In real-world use, the amounts of magnesium stearate present in supplements are very small—typically only a fraction of a gram. The body also metabolizes stearic acid as part of many common foods, so the effects seen in cell studies don't necessarily translate to everyday consumption through supplements.

The Concerns Around Silicon Dioxide

1. Claims of Toxicity

Silicon dioxide is often labeled as potentially toxic by critics who argue that consuming it over long periods could pose health risks. However, silicon dioxide naturally occurs in many foods, and the form used in supplements is typically recognized as safe by regulatory agencies, including the FDA.

Research published in the Food and Chemical Toxicology journal has shown that silicon dioxide, in the small amounts typically used as an anti-caking agent, is not harmful to humans . The European Food Safety Authority has also assessed it and found that silicon dioxide does not accumulate in the body and is excreted without causing toxicity.

2. Respiratory Concerns

Another concern with silicon dioxide is its inhalation during the manufacturing process. In its powdered form, inhaling large amounts of silica dust can indeed be harmful and is associated with lung issues in industrial workers. However, this risk pertains to those exposed to large amounts of inhalable silica over prolonged periods, such as miners or factory workers—not to consumers taking silica-containing supplements.

Why Are They Used in Supplements?

While magnesium stearate and silicon dioxide are often criticized, their use in supplements serves practical purposes:

• Consistency and Quality: These additives help ensure that each capsule or tablet contains the correct dosage of the active ingredients. Without flow agents, supplement production could become inconsistent, leading to variations in dosage that could affect effectiveness and safety.
• Manufacturing Efficiency: Flow agents like magnesium stearate and silicon dioxide help keep production costs down by reducing clumping and preventing damage to machinery. This efficiency is part of why supplements are available at a lower price point.

In small amounts, they make it easier to produce safe, affordable, and effective supplements. However, concerns arise when consumers prefer "clean" supplements that are free from any synthetic additives.

Should You Be Concerned?

Ultimately, the decision to avoid supplements containing magnesium stearate and silicon dioxide comes down to personal preference. For those who are particularly sensitive to additives or who prefer to avoid synthetic ingredients, there are brands that offer "additive-free" or "clean label" supplements. These may be more expensive, but they can offer peace of mind.

For most people, the small amounts of magnesium stearate and silicon dioxide used in supplements are considered safe and unlikely to cause harm. Regulatory bodies like the FDA have deemed these ingredients generally safe for consumption in the quantities found in dietary supplements. It’s always a good idea to do your own research, consult with a healthcare provider, and choose supplements that align with your health goals.

Conclusion: Are Magnesium Stearate and Silicon Dioxide Really the Bad Guys?

Magnesium stearate and silicon dioxide have become somewhat controversial in the supplement world, but their risks are often overstated. While they are not inherently harmful in the small amounts found in supplements, their inclusion does not sit well with everyone, especially those looking for the purest products possible. Understanding why these ingredients are used and weighing the evidence behind their safety can help you make more informed choices about the supplements you take. Ultimately, the best supplement is one that meets your needs while aligning with your values around health and wellness.

All TWO NUTRA BROS products are free from Magnesium Stearate and Silicon Dioxide.

Scientific References

1. Rowe, R. C., et al. (2006). "Magnesium Stearate." Journal of Pharmaceutical Sciences.
2. EFSA Panel on Food Additives (2018). "Safety of silicon dioxide as a food additive." EFSA Journal.
3. Arts, J. H. E., et al. (2007). "Silica nanoparticles: acute toxicity, pharmacokinetics, and organ distribution." Food and Chemical Toxicology.