Diatomaceous earth is a unique type of sand that consists of fossilized algae.
It has been mined for decades and has numerous industrial applications.
More recently, it has appeared on the market as a dietary supplement, claimed to have several health benefits.
This article takes a detailed look at diatomaceous earth and its health effects.
Diatomaceous earth is a naturally occurring sand extracted from the earth.
It consists of microscopic skeletons of algae, known as diatoms, that have fossilized over millions of years (1).
There are two main types of diatomaceous earth: food grade, which is suitable for consumption, and filter grade, which is toxic to humans but has many industrial uses.
The diatoms in diatomaceous earth are largely made up of a chemical compound called silica.
Silica is commonly found in nature, from sand and rocks to plants and humans. However, diatomaceous earth is a concentrated source of silica, which makes it unique (2).
Commercially available diatomaceous earth is said to contain 80 to 90% silica, several other trace minerals and small amounts of iron oxide (rust) (1).
Bottom Line: Diatomaceous earth is a type of sand that consists of fossilized algae. It is rich in silica, a substance that has many industrial uses.
Silica exists in two main forms, crystalline and amorphous (non-crystalline).
The sharp crystalline form looks like glass under a microscope. It has properties that make it desirable for numerous industrial applications.
The two main types of diatomaceous earth vary in their concentrations of crystalline silica:
- Food Grade: This type contains 0.5–2% crystalline silica and is used as an insecticide as well as an anti-caking agent in the agricultural and food industries. It is approved for use by the EPA, USDA and FDA (3, 4).
- Filter Grade: Also known as non-food grade, this type is said to contain upwards of 60% crystalline silica. It is toxic to mammals but has many industrial applications, including water filtration and the production of dynamite.
Bottom Line: Food grade diatomaceous earth is low in crystalline silica and considered safe for humans. The non-food grade type is high in crystalline silica and is toxic.
Food grade diatomaceous earth is often used as an insecticide.
When it comes in contact with an insect, the silica removes the waxy outer coating from the insect's exoskeleton.
Some farmers believe adding diatomaceous earth to the feed of livestock kills internal worms and parasites through similar mechanisms, but this use remains unproven (7).
Bottom Line: Diatomaceous earth is an insecticide that works by removing the waxy outer coating from the exoskeleton of insects. Some believe that it can also kill parasites, but this needs to be researched more.
Food grade diatomaceous earth has recently become popular for humans as a dietary supplement.
It is claimed to have the following health benefits:
- Cleanse the digestive tract.
- Support healthy digestion.
- Improve cholesterol and heart health.
- Provide the body with trace minerals.
- Improve bone health.
- Promote hair growth.
- Promote skin health and strong nails.
However, not many quality human studies have been done on diatomaceous earth as a supplement, so most claims of health benefits are theoretical and anecdotal.
Bottom Line: Supplement manufacturers claim that diatomaceous earth has many health benefits, but they have not been proven in studies.
Silicon — the non-oxidized form of silica — is one of many minerals stored in the human body.
Due to its silica content, some claim that ingesting diatomaceous earth helps increase your silicon levels.
However, because this type of silica does not mix with fluids, it is not well-absorbed, if at all. Imagine placing sand in water. The two just don't mix.
Some researchers speculate that silica may release small but meaningful quantities of silicon that your body can absorb, but this is unproven and unlikely (8).
For this reason, consuming diatomaceous earth probably has no meaningful benefits for bone health.
Bottom Line: Some claim that the silica in diatomaceous earth can increase silicon in your body and strengthen bones, but this hasn't been proven.
One major health claim for diatomaceous earth is that it can help you detox by "cleansing" your digestive tract.
This claim is based on its ability to remove heavy metals from water, which is the property that makes diatomaceous earth a popular industrial-grade filter (11).
However, no scientific evidence verifies that this mechanism can be applied to human digestion — or that it has any meaningful effect on your digestive system.
More importantly, no evidence supports the idea that people's bodies are loaded with toxins that must be removed.
Your body is perfectly capable of of neutralizing and removing toxins itself.
Bottom Line: There is no evidence that diatomaceous earth helps remove toxins from the digestive system.
To date, only one small human study has investigated diatomaceous earth as a dietary supplement.
The study's 19 subjects, all of whom had a history of high cholesterol, took the supplement three times per day for 8 weeks.
LDL (the "bad") cholesterol and triglycerides also decreased slightly, and HDL (the "good") cholesterol levels increased after the study was over (12).
The findings are interesting, but since the study didn't include a control group, it can not prove that diatomaceous earth was actually responsible for lowering cholesterol.
The researchers concluded that a placebo-controlled study is required.
Bottom Line: A small study found that diatomaceous earth can lower cholesterol and triglycerides. The study design was very weak and further research is needed.
Food grade diatomaceous earth is safe to consume. It passes through your digestive system unchanged and does not enter the bloodstream.
However, you need to be very careful not to inhale diatomaceous earth.
If you do that, it will irritate your lungs, much like the inhalation of dust. But the silica makes it exceptionally harmful.
Inhaling crystalline silica can cause inflammation and scarring of the lungs, known as silicosis.
Because food grade diatomaceous earth is less than 2% crystalline silica, you might think it's safe. However, long-term inhalation can still damage your lungs (15).
Bottom Line: Food grade diatomaceous earth is safe to consume, but do not inhale it. It can cause inflammation and scarring of your lungs.