Orthosilicic acid, a water-soluble compound, is represented by the chemical formula Si(OH)₄ or H₄SiO₄. This compound exists primarily in solution as a weak acid. It is considered the bioavailable form of silicon that the human body can readily absorb and utilize.
The Role of Orthosilicic Acid in the Body
Orthosilicic acid plays a role in various bodily processes, particularly those involving connective tissues. It stimulates the synthesis of Type I collagen, which provides structural integrity and elasticity to the skin, hair, and nails. This compound may also modulate the activity of prolyl hydroxylase, an enzyme involved in collagen production.
For skin health, silicon supports collagen synthesis and activates specific hydroxylation enzymes, improving skin strength and elasticity. A decline in silicon levels is associated with reduced moisture and elasticity in aging skin. For hair, higher silicon content is linked to a lower rate of hair loss and increased brightness, and supplementation has been observed to increase hair strength and thickness.
Nails also benefit from silicon, as it is a predominant mineral in their composition. Beyond these external structures, orthosilicic acid contributes to bone health. Silicon participates in bone mineralization, and its presence has been associated with increased bone density. Research indicates a positive correlation between dietary silicon intake and bone mineral density, particularly in men and premenopausal women.
Dietary and Supplemental Sources
Orthosilicic acid is found in various natural dietary sources, primarily from plants. Cereals, such as oats, barley, and rice, along with many fruits and vegetables, contain this compound. Green beans, for example, are recognized for their absorbable silicon content, with approximately 44% absorption observed from consumption. Mineral water and beverages like beer also serve as notable sources, with beer containing between 9 to 39 milligrams of silicon per liter, and mineral water typically providing 2 to 5 milligrams per liter.
While silicon is abundant in many plant foods, its bioavailability can vary significantly due to how it is stored within the plant. For instance, bananas possess a high silicon content, but only about 2% of it is absorbed by the body.
When considering supplemental forms, stabilization is often necessary because orthosilicic acid can polymerize, forming larger, less absorbable molecules. Choline-stabilized orthosilicic acid (ch-OSA) is a widely used supplemental form designed to enhance bioavailability. This stabilization helps maintain orthosilicic acid in its monomeric, water-soluble state, allowing for better absorption.
Understanding Silicon, Silica, and Orthosilicic Acid
Silicon (Si) is the chemical element itself, ranking as the second most abundant element in the Earth’s crust. While silicon is widespread in nature, it is not directly absorbed by the body in its elemental form.
Silica, also known as silicon dioxide (SiO₂), is a common compound composed of silicon and oxygen. This form is prevalent in nature, forming the primary component of sand and quartz. However, silica is largely insoluble and exhibits low bioavailability, meaning the body has difficulty absorbing and utilizing it effectively.
Orthosilicic acid, with the formula Si(OH)₄, represents the water-soluble, monomeric form of silicon. This is the specific form that the body can readily absorb and put to use. To illustrate, consider silicon as a raw mineral. Silica is like an unprocessed chunk, while orthosilicic acid is the refined, soluble version the body can readily use.
Recommended Intake and Safety
There is currently no official Recommended Dietary Allowance (RDA) established for silicon. However, typical daily silicon intake from Western diets generally falls within the range of 20 to 50 milligrams per day. Studies often report average daily intakes for adults around 29 to 33 milligrams of silicon.
When considering supplemental forms, dosages of orthosilicic acid used in scientific studies often provide between 10 to 18 milligrams of silicon per day. For instance, some research involving choline-stabilized orthosilicic acid (ch-OSA) has utilized a daily intake of 10 milligrams of silicon.
Orthosilicic acid and its stabilized compounds are generally considered safe for human consumption at common supplemental levels. It is always advisable to consult with a healthcare professional before beginning any new supplement regimen.