Food-grade diatomaceous earth is a fine, chalky dust made from the fossilized shells of tiny aquatic organisms called diatoms. The powder is highly porous and absorbent. Those physical properties make it useful as a desiccant for pest control and as a filter medium for swimming pools. Its silica is mostly amorphous, a form less bioavailable than the silicon in whole grains.
Gardeners and farmers use the powder externally to kill insects by stripping away their waxy outer coating. Water filtration systems rely on it as well. Some people mix the food-grade powder into water and drink it for perceived detox or parasite-cleansing effects. Solid clinical evidence for those internal uses is missing. Claims about better skin, hair, nails, or digestion remain unverified.
Breathing the dust irritates the lungs. Long-term inhalation can lead to silicosis. Handle the powder carefully and wear a mask when pouring. For any internal use, only choose a product marked "food grade." Pool-filter grades contain crystalline silica and are toxic. Oral ingestion has no well-documented drug interactions, but speak with a doctor before consuming it, especially if you have an existing health condition.