Understanding the Different Grades of Diatomaceous Earth
Not all diatomaceous earth (DE) is created equal, and understanding the critical differences between grades is the most important factor for safety. The two main types are amorphous (food-grade) and crystalline (filter-grade) silica, which have vastly different applications and safety profiles.
Food-Grade Diatomaceous Earth
Food-grade DE is derived from freshwater diatoms and is composed primarily of amorphous silica. It is processed to contain a very low percentage (less than 2%) of crystalline silica, making it safe for use in animal feed and as an anti-caking agent. For dietary purposes, it is the only type ever considered for internal consumption. The particles are sharp enough to harm insects but are harmless to mammals when ingested, as they pass through the digestive system largely unchanged.
Filter-Grade Diatomaceous Earth
Filter-grade DE, also known as pool-grade, is sourced from saltwater diatoms and undergoes high-heat processing (calcination). This process significantly increases the concentration of crystalline silica, which is highly toxic when inhaled. Filter-grade DE is explicitly not safe for consumption by humans or animals. It is a severe respiratory hazard, and long-term inhalation can lead to serious lung conditions like silicosis and lung cancer.
The Scarcity of Research on Daily Consumption
While the FDA considers food-grade DE safe as an indirect food additive, its regulation and approval as a daily dietary supplement is lacking. As a result, there is no official recommended daily intake or scientific consensus on its long-term health effects. The marketing surrounding DE often cites potential benefits such as detoxification, improved digestion, and healthier hair and nails, but these claims are based largely on anecdotal evidence and small, uncontrolled studies.
For example, one small 1998 human study observed a drop in cholesterol levels among participants taking DE over eight weeks, but the lack of a control group means the results are not conclusive. The absence of robust, long-term human studies is a significant reason why healthcare professionals often advise caution and recommend exploring more scientifically-backed alternatives.
Potential Side Effects and Safety Concerns
While food-grade DE is considered safe for ingestion, there are still risks associated with daily use, primarily due to its physical properties and the lack of research.
-
Respiratory Risks: The most significant danger comes from inhalation. Even food-grade DE is a fine powder that can irritate the nasal passages and lungs if breathed in. Regular, low-level inhalation of any form of silica dust can increase the risk of respiratory problems. When handling the powder, wearing a mask and working in a well-ventilated area is essential to minimize this risk.
-
Gastrointestinal Discomfort: Some individuals, particularly when first starting a regimen, report digestive issues such as bloating, constipation, or upset stomach. This may be due to the product's gritty, absorbent nature. Adequate hydration is crucial to help prevent constipation.
-
Drying Effects: The abrasive and absorbent qualities of DE can cause dryness and irritation to skin and mucous membranes if contact occurs. Eye protection and careful handling are important.
-
Herxheimer Reaction: Some users undergoing a "detox" with DE report experiencing temporary, flu-like symptoms, which are sometimes attributed to a Herxheimer reaction (a reaction to toxins being released from dying microorganisms). While this is anecdotal, it's a possibility to be aware of and can be managed by adjusting the dosage.
Food-Grade vs. Filter-Grade Diatomaceous Earth: A Key Comparison
| Feature | Food-Grade DE | Filter-Grade DE |
|---|---|---|
| Source | Freshwater diatoms | Saltwater diatoms |
| Processing | Minimally processed | Heat-treated (calcined) |
| Silica Type | Amorphous (less than 2% crystalline) | High crystalline silica (around 60%) |
| Ingestion Safety | Generally recognized as safe (GRAS) by FDA in low concentrations as an additive. Unregulated as a supplement. | Highly toxic and never safe for consumption |
| Inhalation Risk | Irritating to lungs if inhaled frequently | Severe respiratory hazard; can cause silicosis and lung damage |
| Primary Use | Insecticide, anti-caking agent, and supplement (anecdotal) | Water filtration, industrial use |
Expert Recommendations and Alternative Approaches
Given the lack of conclusive scientific evidence for benefits and the potential, albeit limited, risks associated with long-term, daily use, most health experts recommend caution. For those interested in boosting silica intake or promoting detox, there are more traditional and scientifically supported methods. Consider incorporating silica-rich foods into your diet, such as bananas, green beans, and oats. These provide silica alongside other beneficial nutrients in a much safer, natural form.
Best Practices if You Choose to Proceed
If, after considering the above, you still wish to use food-grade diatomaceous earth daily, follow these best practices for maximum safety:
- Choose the Right Product: Only ever use a product explicitly labeled as "food-grade". Look for certifications from third-party organizations like the Organic Materials Review Institute (OMRI) for extra assurance of purity.
- Start with a Low Dose: Begin with a very small amount, like half a teaspoon, and gradually increase it over several weeks to see how your body reacts. Some sources suggest starting with one teaspoon in a glass of water and working up to a tablespoon daily.
- Stay Hydrated: Drink plenty of extra water throughout the day to prevent the constipation that can arise from the absorbent nature of the supplement.
- Minimize Inhalation: Always mix the powder into a liquid immediately to prevent airborne dust. Consider wearing a dust mask when handling larger quantities.
- Consider Cycling: Instead of taking it every day indefinitely, some proponents suggest cycling on and off the supplement, for example, taking it daily for a few weeks, then taking a break.
- Consult a Professional: Always speak with a healthcare provider, especially if you have pre-existing digestive or respiratory conditions, or if you are pregnant or nursing.
Conclusion
While food-grade diatomaceous earth is not acutely toxic, its long-term effects as a daily dietary supplement are not well-researched, and the anecdotal health claims lack strong scientific support. The risks, particularly from inhalation, are real and significant for the more toxic filter-grade product, and caution must be exercised with any form of the powder. For most people, incorporating silica-rich foods is a safer and more established way to support health. If daily consumption is pursued, it is critical to use only food-grade products, start with a low dose, and prioritize safety protocols like minimizing inhalation. The overarching recommendation from health experts is to remain skeptical of unsubstantiated claims and consult a professional before starting any new supplement regimen.
Resources
For more information on the distinctions between amorphous and crystalline silica, visit the CDC's National Institute for Occupational Safety and Health (NIOSH) website.
Note: The content of this article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional before making any changes to your diet or health regimen.
