Silica, also known as silicon dioxide or SiO2, is a colorless, white, chemical compound. Silica is made of the most common elements on earth, silicon (Si) and oxygen (O2). It’s also the most abundant compound in the earth's crust, where it makes up 59% of the total composition. Silica is used everywhere, from industrial applications to the food and beverage industry.
You’ll find silica in a lot of places — food, rocks, plants, medicine, cosmetics, toothpaste, and those little dry gel packs that are packed in with product packaging to absorb moisture. There’s even silica in your body. The most common form of silica is quartz, a component of stone, concrete, and sand. Simply put, silica is everywhere. If you’ve touched a rock or been to the beach, you’ve handled silica. Don’t worry— it’s mostly harmless and can even be beneficial.
The Role of Silica in Your Body
Humans use silica as a food additive and a filler in drugs and vitamins. It has a low bioavailability, meaning your body will only absorb a tiny amount of silica and excrete the rest in urine. Most of the silica in your body is in a form called orthosilicic acid. It exists in your bones, tendons, aorta, liver, and kidneys.
Health Benefits of Silica
The exact role of silica in human health is still unclear. It may support bone health and the creation and maintenance of connective tissue. Orthosilicic acid supplements have shown positive effects on skin, hair, and nails by keeping these parts supple and preventing brittleness. Orthosilicic acid may help block the neurotoxic effects of aluminum and it's linked to normal immune system health.
Dangers of Silica
Silica used in the food and beverage industry is safe to take orally. However, that doesn't mean that silica is always safe for humans. Silica actually comes in many forms — some safe, some not.
Crystalline silica, a form that includes quartz, can be toxic if inhaled. Crystalline silica is found in rock, brick, and concrete. Grinding, sawing, crushing, or drilling these materials produces a fine powder that causes serious respiratory concerns. It is possible for homes to retain this sort of dust after a construction or remodeling project but, most of the time, unless you work on a construction site or quarry, you probably don’t have to worry about crystalline silica powder. If you do work at a place like this, it’s vital that you wear an appropriate dust mask or respirator.
Diet and Silica Supplementation
Silica is naturally present in many foods and it’s actually essential to a healthy diet. In fact, natural levels of silica are higher in plant-derived foods than in meat or dairy products. One well-known plant with a high amount of silica is horsetail.  You can also obtain silica from other natural sources such as diatomaceous earth, a thick, white, siliceous powder that has a variety of uses. Supplements are another way to obtain the necessary amount of silica your body needs.
Silica hydrate is the result of silica binding to water molecules. When taken as a supplement, it hydrates cells and acts as a powerful antioxidant. Silica hydrate neutralizes free radicals to help preserve cellular and molecular integrity. Like other antioxidants, it scavenges free radicals without becoming one itself.
Silica is all around us and inside us. It comes in many forms. Some, like crystalline silica, are harmful. Others, like silica hydrate, are amazingly beneficial. There is still a lot of research that needs to be done on silica and its effects on the human body, but it seems to have the potential to be amazing.
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†Results may vary. Information and statements made are for education purposes and are not intended to replace the advice of your doctor. If you have a severe medical condition or health concern, see your physician.