Silica, also known as silicon dioxide, has been traditionally used in various cultures for supporting hair health, but there is also some scientific interest in its potential benefits. Silica is believed to play a role in the structural integrity of hair, skin, and nails due to its involvement in collagen synthesis and connective tissue health. Some small clinical studies suggest that silicon supplementation may improve hair strength and thickness. For example, a randomized, double-blind study published in 2007 found that women who took a silicon-rich supplement for nine months showed significant improvements in hair tensile strength and a reduction in hair breakage compared to a placebo group (Arch Dermatol Res, 2007).

However, the overall quality and quantity of scientific evidence remain limited. Most studies are small, short-term, and use varying forms of silicon, making it difficult to draw firm conclusions about efficacy. While mechanistic studies suggest that silicon is important for keratin and collagen formation—key components of hair structure—there is not yet a consensus in the scientific community regarding optimal dosing or clinical significance for hair health.

In summary, while there is both traditional use and some scientific support for the role of silica in supporting hair health, the strength of the scientific evidence is modest rather than robust. More large-scale, high-quality clinical trials are needed to confirm its benefits and to determine effective dosing strategies.