Are Silica Supplements Safe?

Silica — not to be confused with human-made silicone — is a naturally occurring compound and popular supplement.

People take silica supplements for potential benefits to hair, skin, nails, and bone health, though more research is needed to confirm these effects.

Additionally, there are risks to taking substances that aren’t rigorously tested, and most supplements sold in the US are only lightly regulated.

Here’s what you need to know about the effectiveness and risks of taking silica.

What is Silica?

Silica — or silicon dioxide — is a naturally occurring compound made of silicon and oxygen, according to a 2020 review in Applied Sciences. Silicon is the element your body actually uses, in trace amounts, once it’s absorbed from silica.

Silicon performs a number of important functions in the human body, including the production of skin, hair, and nails, according to the 2020 review.

Natural sources of silica include fruits, vegetables, cereals, and mineral water, but people also take the compound as a supplement. It is also a popular food additive and anti-clumping agent.

What are the Benefits of Silica?

There are very few recent studies conducted on the benefits of silica, and even fewer high-quality human trials.

One of the most significant studies, a double-blind trial published in 2005 in Archives of Dermatological Research, found that women who took orthosilicic acid (also known as soluble silica) for 20 weeks showed skin improvements and decreased hair and nail brittleness.

Is Silica Safe?

First and foremost, the U.S. Food and Drug Administration (FDA) does not review or test supplements, so there is no guarantee that a silica in supplement form is as safe or effective as manufacturers claim.

Additionally, more studies are needed to test silica supplement safety and efficacy, according to a review published in 2016 in Anais Brasileiros de Dermatologia.

However, the 2020 review in Applied Sciences found no evidence of adverse effects in human or animal studies for most doses of silicon found in food and supplements.

As a general rule, talk to your doctor before trying any supplement to make sure it's right for you.