Silica pills and liquid formulas are marketed for their ability to strengthen the bones, improve skin health and repair damaged tissues. Most supplements contain silica — or silicon dioxide (SiO2) — derived from horsetail extract. This compound consists of silicon and oxygen and makes up about 59 percent of the earth's crust. In addition to its industrial uses, it's promoted as a natural remedy for healthy skin, hair and nails.
Crystalline silica is highly toxic and may cause lung cancer. Supplements contain dietary silica, which is considered safe when consumed in appropriate doses.
What Is Silica?
According to the European Association of Industrial Silica Products, this trace mineral exists in nine different forms, including quartz and cristobalite. Crystalline silica is used in various industries, from glass and construction to agriculture. When inhaled, it may lead to respiratory disorders, lung cancer, kidney disease and other ailments.
Dietary supplements contain other forms of silica that are generally safe and unlikely to cause side effects, according to a review published in the journal Nutrition & Metabolism in January 2013. Silicon dioxide and ortho-silicic acid, for example, occur naturally in whole grains, fruits and veggies. Meat, dairy and other animal products are lower in silicon dioxide than plant-based foods. Beer and mineral waters contain this compound, too.
The review highlights the potential health benefits of silicon and its derivatives. According to researchers, silica is a form of silicon. This natural element plays a key role in collagen synthesis, immune function, bone mineralization and mental health. It is also the third most abundant trace mineral in your body. Most studies suggest that ortho-silicic acid exhibits therapeutic effects and may benefit overall health.
Potential Benefits of Silica Pills
Silica pills contain dietary silicon. This natural compound may improve bone health in middle-aged women, according to a cohort study published in March 2012 edition of the journal Bone. Researchers state that silica, that is, silicon dioxide, interacts with estrogen, leading to increased bone mineral density.
If you're struggling with hair loss or dull skin, silica might help. This trace element stimulates collagen synthesis, keeping your skin young and firm. It may also reduce hair loss and build stronger nails, according to a May/June 2016 review featured in Anais Brasileiros de Dermatologia. In the clinical trials cited in the review, silicon supplements were shown to improve skin appearance and increase hair resistance to breakage.
Read more: The 12 Best Foods for Healthy Hair
The review published in Nutrition & Metabolism suggests that silica has far more benefits than was once thought. As researchers note, silicon supplements may help prevent degenerative diseases and improve immune function. However, most studies have been conducted on animals, so it's hard to say whether these findings would apply to humans.
Silica Side Effects and Risks
Silica, i.e. silicon dioxide, is widely used as an anticaking agent. According to the FDA, this compound should not exceed two percent of a food's total weight.
Dietary supplements, though, fall under a different set of regulations. The FDA takes action against potentially harmful products only after they enter the market. Therefore, it's your responsibility as a customer to check the labels and make an informed decision.
Prolonged exposure to crystalline silica may cause toxicity. Lung damage and chronic obstructive pulmonary disease are common side effects. However, crystalline silica has a different chemical makeup than dietary silica, so the dietary form doesn't carry these risks.
According to the journal Nutrition & Metabolism, the safer upper limit for silicon dioxide is around 700 milligrams per day. Whole grains provide approximately one-third of total silicon intake in a typical diet.
Silica is a naturally occurring element that can be found in most foods. Therefore, it's unlikely to cause adverse reactions when consumed in appropriate doses. To stay safe, consult your doctor — especially if you want to take silica during pregnancy or while breastfeeding.
- Britannica: "Silica"
- Eurosil: "What Is Silica?"
- OSHA: "Silica, Crystalline"
- BMC Nutrition & Metabolism: "Biological and Therapeutic Effects of Ortho-Silicic Acid and Some Ortho-Silicic Acid-Releasing Compounds: New Perspectives for Therapy"
- NCBI: "Dietary Silicon Interacts With Oestrogen to Influence Bone Health: Evidence From the Aberdeen Prospective Osteoporosis Screening Study"
- Scielo: "Use of Silicon for Skin and Hair Care: An Approach of Chemical Forms Available and Efficacy"
- FDA: "CFR - Code of Federal Regulations Title 21 - Silicon Dioxide"
- FDA: "FDA 101: Dietary Supplements"
- Silica Safe: "What Are the Health Effects?"
- Swanson Vitamins: "NOW Foods Silica Complex"
- Swanson Vitamins: "BioSil - Hair, Skin, Nails"