Limited evidenceGut health

Diatomaceous Earth

Fossilized algae powder marketed for parasites, detox, cholesterol and 'silica for hair and nails'. Human evidence is essentially nonexistent — the parasite claim rests on how it kills insects mechanically, which does not transfer to the human gut — and the inhalation hazard is real.

What the science says

Kills intestinal parasites Limited evidence
Diatomaceous earth kills insects by abrading their waxy exoskeleton and desiccating them, which requires a dry environment. Human intestinal parasites have no waxy cuticle to abrade and live in a wet lumen, so the mechanism does not apply. There are no human trials, and even in livestock the anthelmintic results are inconsistent.
Lowers cholesterol Limited evidence
The claim traces to a small uncontrolled 1990s pilot in hypercholesterolemic adults reporting reduced total cholesterol on 750 mg three times daily; with no control group and no replication, it carries little weight. A 2025 study in healthy female rats found diatomaceous earth as a bioavailable silicon source altered postprandial lipid handling — an interesting animal signal, not a human result.
Provides bioavailable silica for skin, hair and nails Limited evidence
Food-grade DE is roughly 80-90% amorphous silicon dioxide, but most of it is insoluble and passes through unabsorbed. Comparative human data show soluble orthosilicic acid is absorbed far better than particulate or polymerized silica. No trial has tested diatomaceous earth on hair, skin or nail outcomes in people.
Acts as a detox or heavy-metal binder Limited evidence
DE has adsorptive surface area and is used industrially as a filtration medium, which is the whole basis of the marketing. No human study has shown that ingesting it lowers body burden of any toxin or metal.

Dosage & safety

Studied doseNo evidence-based human dose exists. Consumer labels suggest 1-2 tablespoons (roughly 5-15 g) daily in water; the small cholesterol pilot used 750 mg three times daily. If used at all, only food-grade (amorphous) diatomaceous earth is appropriate, and always with plenty of fluid.

SafetyThe critical distinction is food-grade (amorphous silica, low crystalline content) versus pool/filter-grade (calcined, high crystalline silica) — the latter must never be ingested or handled without respiratory protection. Inhaling the dust of any DE product is the main hazard: crystalline silica inhalation causes silicosis and is a Group 1 lung carcinogen, and chronic amorphous silica exposure has been linked to pneumoconiosis. Never mix it in a way that raises dust; wear a mask. Orally, expect constipation, bloating and possible obstruction without adequate fluid. Regulators have noted incomplete safety data for nano-structured and amorphous silica additives at high oral intakes. It also nonspecifically adsorbs medications — separate by 2-3 hours. Avoid in pregnancy, children, and anyone with swallowing or bowel motility problems.

Scientific references

Diatomaceous Earth Supplementation as a Bioavailable Silicon Source Modulates Postprandial Lipid Metabolism in Healthy Female Rats
Redondo-Castillejo R, Hernández-Martín M, Issa-García JÁ, et al — Nutrients, 2025
Critical review of the safety assessment of nano-structured silica additives in food
Winkler HC, Suter M, Naegeli H — J Nanobiotechnology, 2016

Where to buy

Starwest Botanicals, Diatomaceous Earth, 1 lb (453.6 g)

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