Silicon is one of the most prevalent elements on earth; it makes up more than a quarter of the earth’s crust, mostly as silicon dioxide. Silicon is hypothesized to play an essential role in the body, but this is uncertain. Silicon supplements are currently marketed for improving the health of bone, skin, hair, and nails. The substance silicone, once used in breast implants, also contains silicon, but in an unusual synthetic form.

Scientists have found it difficult to determine whether silicon is an essential nutrient in humans, and if it is, to identify the necessary daily intake.1 Silicon is found whole grains, some root vegetables, and beer. Silicon-containing chemicals are also added to prevent caking in products such as salt and baking soda. The average intake of silicon is approximately 10–40 mg daily.