What Exactly is Food-Grade Diatomaceous Earth?
Food-grade diatomaceous earth (DE) is a soft, fine powder made from the fossilized remains of ancient, hard-shelled algae called diatoms. Their skeletons are composed of amorphous silica, a form of silicon dioxide that is considered non-toxic to humans when ingested. This differs significantly from filter-grade or industrial-grade DE, which is heat-treated and contains a much higher concentration of crystalline silica, a known respiratory hazard.
The FDA’s GRAS (Generally Recognized as Safe) designation for food-grade DE applies primarily to its use in low concentrations as an anti-caking agent or processing aid in food products, not as a daily dietary supplement. Because dietary supplements are not strictly regulated by the FDA, the onus is on the consumer to research and understand the product they are purchasing. Always ensure the product is certified food-grade, ideally from a trusted source that tests for heavy metals and meets purity standards.
The Difference Between Food-Grade and Filter-Grade DE
Understanding the distinction between the different grades of diatomaceous earth is crucial for safety. Using the wrong grade can have serious health consequences, particularly when it comes to inhalation.
Food-Grade DE
- Composition: Primarily amorphous silica, with less than 1% crystalline silica.
- Source: Mined from freshwater lakebeds.
- Safety: Generally recognized as safe for ingestion in small quantities. Safe for use as an insecticide in homes and on pets.
- Risks: Minor, including digestive upset. Major risk comes from inhalation, which can irritate the lungs.
Filter-Grade DE
- Composition: Calcined (heat-treated) to contain high levels of crystalline silica, often 60% or more.
- Source: Often sourced from saltwater, with different processing.
- Safety: Not safe for human or animal ingestion or inhalation. Used primarily for industrial filtration, such as in swimming pools.
- Risks: Highly toxic if inhaled, with long-term exposure leading to serious lung conditions like silicosis and lung cancer.
Potential Health Benefits: Separating Fact from Anecdote
Many online resources promote food-grade DE as a health elixir, attributing various benefits to its high silica content. These claims, however, are largely theoretical and not backed by robust, peer-reviewed human studies.
Anecdotal Claims vs. Scientific Evidence
- Detoxification: Proponents suggest DE's porous structure can bind to heavy metals and toxins in the digestive tract. While industrial-grade DE is used for water filtration, this process has not been proven to occur effectively within the human digestive system.
- Improved Digestion: It is claimed that DE acts as a natural internal cleanser, promoting regular bowel movements. Some users report this benefit, but it lacks definitive scientific proof.
- Bone and Joint Health: Since silica is an important mineral for connective tissues, some believe supplementing with DE can improve bone mineral density. Research on this topic is still emerging and inconclusive.
- Better Skin, Hair, and Nails: A high silica intake is theorized to boost collagen production, leading to healthier skin, hair, and nails. While silica is essential for these tissues, it is not proven that consuming DE is a superior method of intake compared to dietary sources.
- Lowered Cholesterol: A single, small-scale human study from 1998 showed a decrease in total cholesterol among participants taking DE. However, it lacked a control group, and the researchers noted that further placebo-controlled studies are needed to confirm the findings.
Safe Handling and Consumption Practices
If you do choose to use food-grade diatomaceous earth, it is essential to follow safe handling and consumption guidelines to minimize risks.
Proper Usage for Human Consumption
- Start Low and Go Slow: Begin with a low dose, such as one teaspoon mixed into a glass of water, and gradually increase it over time to assess your tolerance.
- Mix with Liquid: Because it does not dissolve, mix the powder thoroughly into a liquid like water or juice and drink immediately before it settles. Some find it more palatable in yogurt or a smoothie.
- Stay Hydrated: Consume plenty of water throughout the day, as DE is absorbent and can potentially cause constipation if you don't drink enough fluids.
- Avoid Inhaling: Always be careful when handling the powder. Avoid creating dust and wear a mask if needed, as inhalation can irritate the lungs.
Comparison of Food-Grade vs. Filter-Grade DE
| Feature | Food-Grade Diatomaceous Earth | Filter-Grade Diatomaceous Earth |
|---|---|---|
| Composition | Mostly Amorphous Silica | Mostly Crystalline Silica |
| Processing | Mined from freshwater deposits | Heat-treated (calcined) for filtration |
| Primary Use | Dietary supplement (anecdotal), pesticide, anti-caking agent | Industrial filtration (e.g., pools) |
| Heavy Metals | Strict, low-level specifications | Less regulated for heavy metals |
| Human Ingestion | Recognized as safe for indirect use (GRAS) | NOT SAFE for ingestion |
| Inhalation Risk | Avoid inhalation to prevent respiratory irritation | HIGHLY DANGEROUS; linked to silicosis |
| Effectiveness as Supplement | Largely anecdotal, minimal scientific evidence | Not for supplement use |
Conclusion
While food-grade diatomaceous earth is legally recognized as safe for specific food-processing applications by the FDA, its safety and efficacy as a regular dietary supplement for humans is not well-supported by scientific research. Any claims of extensive health benefits, such as detoxification or improved joint health, are largely anecdotal. Users should exercise caution, always purchase a certified food-grade product, and strictly avoid inhaling the powder due to respiratory risks. As with any new supplement, it is prudent to consult a healthcare professional before beginning a regimen, especially for those with pre-existing health conditions, or who are pregnant or nursing. The primary danger lies in confusing food-grade DE with industrial-grade products, which are toxic and should never be ingested. For those seeking silica benefits, consuming silica-rich foods remains the most expert-recommended alternative.
