Silicon dioxide, also listed as E551, is a naturally occurring mineral compound also found in trace amounts in foods like leafy greens, grains and mineral water. In powdered supplements, it's used in tiny amounts as an anti-caking agent — it keeps fine powders like protein, creatine or vitamin blends flowing freely instead of clumping together in humid conditions.

It's added at very low levels (typically well under 2% of a formula) and is one of the most widely used and studied anti-caking agents in the food industry, approved for use in food-grade applications across most major regulatory bodies. It passes through the digestive system largely unabsorbed.

If you're buying anti-caking agent separately for your own blending or baking, it's worth confirming you're using a food-grade product intended for consumption, at the recommended usage rate for your recipe.

See our Food Grade Silicon Dioxide E551 listing for current specs and usage guidance.