Silica

Vaguely defined term for minerals and sediments with a high silicon content. Originally, the term silica was used to describe minerals that were suitable for the production of glass due to their quartz content. Silica is offered as a dietary supplement. The amount of silicon dioxide (silica) required by the body is covered by the normal diet. Silicon is contained in potatoes or wholemeal products, for example.

The mechanism of the positive effect of silica on hair and nails is largely unexplained, but is thought to be due to the increase in hydroxyproline in the dermis caused by oral silicon administration (silicon supplements).

The term silica is derived from "diatoms", which have a silicon-containing cell envelope that is preserved after their death and thus forms the basic material of silica. As a homeopathic remedy, silica is also known as Silicea terra, while silicic acid is known as Acidum silicium.

Chemically, silica is a silicic anhydride, i.e. silicon dioxide and not silicic acid. Occasionally, aluminosilicates (alumosilicates) such as kaolins are also called silica. They contain SiO2 and Al2O3.

1. Gehring W (2010) Effect of oral administration of silica on hair quality. Act Dermatol 36: 414-417
2. Wickett RR (2007) Effect of oral intake of choline stabilized orthosilic on hair tensilestrength and morphology in women with fine hair. Arch Dermatol Res 299: 499-505