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, promoted as having 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 inedible 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 as a component of everything 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 80–90% silica, several other trace minerals, and small amounts of iron oxide (rust) (1).
SUMMARY Diatomaceous earth is a type of sand that consists of fossilized algae. It’s 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 and 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 contains upwards of 60% crystalline silica. It is toxic to mammals but has many industrial uses, including water filtration and dynamite production.
SUMMARY Food-grade diatomaceous earth is low in crystalline silica and considered safe for humans. The filter-grade type is high in crystalline silica and toxic to humans.
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 that adding diatomaceous earth to livestock feed kills internal worms and parasites through similar mechanisms, but this use remains unproven (7).
SUMMARY Diatomaceous earth is used as an insecticide to remove the waxy outer coating from the exoskeleton of insects. Some believe that it can also kill parasites, but this needs further research.
Food-grade diatomaceous earth has recently become popular 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 of these claims are theoretical and anecdotal.
SUMMARY 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 your 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.
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.
SUMMARY 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 neutralizing and removing toxins itself.
SUMMARY There is no evidence that diatomaceous earth helps remove toxins from your digestive system.
To date, only one small human study — which was conducted in 19 people with a history of high cholesterol — has investigated diatomaceous earth as a dietary supplement.
Participants took the supplement three times daily for eight weeks. At the end of the study, total cholesterol went down by 13.2%, “bad” LDL cholesterol and triglycerides decreased slightly, and “good” HDL cholesterol increased (12).
However, since this trial didn't include a control group, it cannot prove that diatomaceous earth was responsible for lowering cholesterol.
The researchers concluded that a placebo-controlled study is required.
SUMMARY One 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.
Doing so 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 your 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).
SUMMARY Food-grade diatomaceous earth is safe to consume, but do not inhale it. It can cause inflammation and scarring of your lungs.