Silicon Dioxide vs Mono- and Diglycerides: which is worse?

What is Silicon Dioxide?

Silicon dioxide (silica) is a naturally occurring mineral compound used as an anti-caking agent in powdered and granular foods. The food-grade form is amorphous (non-crystalline) synthetic silica, distinct from the crystalline quartz form associated with lung disease. It absorbs moisture and prevents clumping in powders.

What is Mono- and Diglycerides?

Mono- and diglycerides are emulsifiers derived from glycerol and fatty acids, most commonly sourced from soybean, palm, or sunflower oil. They are partial glycerides that exist between monoglycerides (one fatty acid chain) and diglycerides (two chains). They are chemically similar to fats but are not classified as trans fats even when made from partially hydrogenated sources.

Documented risks

Silicon Dioxide: Food-grade amorphous silicon dioxide is generally recognized as safe. EFSA re-evaluated it in 2018 and concluded there was no safety concern at typical dietary exposure levels; however, the panel noted uncertainty about nanoparticle forms. The food form should not be confused with crystalline silica (quartz) dust, which is a recognized carcinogen when inhaled occupationally. Ingested amorphous silica passes through the body largely unabsorbed.

Mono- and Diglycerides: Generally recognized as safe at typical food levels. However, mono- and diglycerides can be derived from partially hydrogenated oils, meaning they may carry trace trans fats that do not appear on the trans fat label because they are classified as emulsifiers, not fats. Some researchers have noted this labeling gap. A 2019 study published in Lipids in Health and Disease noted potential concerns with industrial trans fatty acids in these additives. For most consumers, exposure is low, and regulatory agencies including FDA and EFSA consider them safe at permitted levels.