Have you ever used diatomaceous earth to kill pests around your home? A lot of people have. But have you ever stirred some into your morning green drink? If you said yes, no, or have no idea what we're even talking about, we invite you to come along as we uncover everything you need to know about diatomaceous earth—from pest control to, yes, health food.
What Is Diatomaceous Earth?
Diatomaceous earth (DE), also known as diatomite, is a type of sedimentary deposit formed from the fossilized remains of diatoms—single-celled algae that first appeared approximately 150 million years ago. The sedimentary deposits that characterize diatomaceous earth form when diatoms die and their exoskeletons remain behind.
The exoskeletons of diatoms are composed of silica—a compound that in turn is made up of oxygen atoms and the element silicon. Silicon is actually the second most plentiful element in the earth's crust, after oxygen. In fact, silicon bonds so readily with oxygen that it's almost never found in nature in its pure state. Instead, you're more likely to find it as silicon dioxide (which, rather confusingly, is also known as silica).
Silicon dioxide occurs in nature in either an amorphous or crystalline form. The vast majority of diatomaceous earth is made up of amorphous silicon, or amorphous silica, as it's also known. However, if silica is heated to high heat via either industrial processing or proximity or volcanic activity, it becomes crystalline.
Crystalline vs. Amorphous Silica
While diatomaceous earth is porous by nature, when it comes to choosing a particular diatomaceous earth product, it all comes down to the difference between crystalline silica and amorphous silica.
Crystalline silica is defined by its lattice shape—think quartz, which is a type of naturally occurring crystalline silica. This crystalline structure means that this type of silica is rife with jagged edges. Which is why breathing crystalline silica is dangerous—the jagged edges can lodge in the lungs and cause scarring called silicosis, which can make it difficult to breathe.
By contrast, amorphous silica is the polar opposite of the crystalline form. Instead of having a clearly defined struecture, the atoms in amorphous silica are arranged in an irregular fashion, which results in a distinct lack of sharp edges—think the smoothness of glass or plastic. Amorphous silica is the type of silica plants contain and, unlike crystalline silica, amorphous silica is considred only a "nuisance" dust by the Occupational Safety and Health Administration (OSHA).
Types of Diatomaceous Earth Products
When purchasing diatomaceous earth, you'll likely run into either filter grade or food grade. Filter grade, or pool grade, diatomaceous earth is composed of crystalline silica, which is much harder than amorphous silica, making it suitable for use in swimming pools and even beer and wine making. This is the form of diatomaceous earth that can cause silicosis if inhaled in large amounts.
By contrast, food grade diatomaceous earth is considered GRAS, or generally regarded as safe, by the U.S. Food and Drug Administration (FDA) because it contains 3% or less of crystalline silica and has been tested for heavy metals.
Food grade DE is sold as bug killer and as a trace mineral supplement for both animal and human consumption. However, many manufacturers that market food grade DE that's specifically for consumption use diatomaceous earth that contains 0.5% or less of crystalline silica.
You're probably wondering how something that can kill insects could possibly be taken internally, or have any potential health benefits.
But it's not as unbelievable as it sounds. In fact, you're very likely eating diatomaceous earth every day without knowing it, as the porosity and shape of the diatoms make them perfect for use as anticaking agents. Diatomaceous earth is also commonly included in products as varied as toothpaste, beverages, food, medications, and vitamin and mineral supplements.
Diatomaceous Earth for Insect Control
While diatomaceous earth may not exactly be mainstream as far as pest control goes, it's actually been an integral part of farming and gardening for decades. In fact, it's often used in grain bins to protect grain stores from insect infestations.
How does diatomaceous earth work?
The diatoms in food grade DE are shaped like tubes, and their sides are covered with holes. These two properties combine to make diatomaceous earth very good at pulling fluids from the exoskeletons and bodies of insects, causing them to dry out and die. The edges of the diatoms are also thought to function as abrasives that help speed up this process.
Diatomaceous earth has been found to be effective against a number of home, farm, and garden pests, including:
One of the great things about food grade diatomaceous earth as a bug killer is that it's both environmentally friendly and completely harmless to children and pets. It can be used for dusting on and around plants to protect them from pests. It can be applied in and around the home as a flea and spider repellent. It can even be used as flea control for pets and a dusting agent to keep mites off chickens.
The only caveat is that diatomaceous earth is a fine powder and must be used dry to be effective against insects. So, if used outside, it needs to be reapplied after every rain or heavy morning dew.
Health Benefits of Diatomaceous Earth
We said earlier that the same food grade diatomaceous earth that kills pests also has health benefits for us humans, but you may still be asking yourself why.
Well, it's because this off-white powder is made up of approximately 90% silicon dioxide. And when you think of how prevalent silica is in the environment, it makes sense that it would be important to us as well.
And it is.
In fact, a deficiency in silica is associated with imbalances in other minerals, like magnesium and calcium, as well as decreased bone mineralization and connective tissue health. Silica is also necessary for healthy skin, hair, teeth, and nails and is even associated with immune system, brain, and heart health.
One small study published in the European Journal of Medical Research found that participants who took 250 milligrams of diatomaceous earth 3 times daily for 8 weeks experienced significant reductions in cholesterol levels.
An interesting but small study published in the Journal of Alzheimer's Disease looking at the association between aluminum and Alzheimer's found that Alzheimer's patients who drank up to a liter of mineral water enriched with silicon every day for 12 weeks not only eliminated higher amounts of aluminum in their urine, but "at least 3 out of 15 individuals" also experienced improvement in cognitive performance.
And silica isn't the only element diatomaceous earth has to offer. It also contains many other important trace minerals, including:
Diatomaceous Earth for Detox?
If you spend any time online looking for information about diatomaceous earth, you're going to run into a number of sites claiming that DE can do everything from treat internal parasites to assist with weight loss to detox the body of heavy metals.
While some of these claims are theoretically possible, there's very little scientific evidence to fully back them up.
For example, studies have found that silicon can reduce levels of heavy metals in soil and can even help plants block the uptake of these dangerous contaminants. However, you'd be hard-pressed to find similar studies involving humans. So we can mark this claim as theoretically possible but not yet proven.
The claim regarding diatomaceous earth and weight loss is similarly unproven and itself rests on the assertion that DE can indirectly aid weight loss by reducing levels of toxins in the body. Again, there are no studies to prove or disprove this claim.
But the claim regarding diatomaceous earth and internal parasites may be the biggest outlier, as we've already shown that DE eliminates pests by drying them out. However, it itself has to be kept dry to do this, so it doesn't seem even theoretically possible that it could have the same effect when taken internally, as it's certainly no longer dry once ingested.
But all these claims aside, diatomaceous earth has certainly proven itself a valuable ally in the fight against home, farm, and garden pests. And its high silica content offers real potential health benefits that can't be ignored.