Silicon (Si) is a trace mineral found naturally in the body, recognized for its widespread presence in various tissues and fluids. It is the third most abundant trace element, and its presence is considered important for health and stability. When consumed through diet or supplements, silicon is often discussed in the form of silica (silicon dioxide) or as its water-soluble counterpart, orthosilicic acid. This highly bioavailable form is how the mineral is primarily absorbed and utilized by the body.
Essential Role in Bone and Skeletal Structure
Silicon plays a role in the development and maintenance of hard tissues, particularly in the process of bone formation. The mineral is heavily involved in the initial phases of bone mineralization, acting as a facilitator rather than a primary structural component like calcium. High concentrations of silicon are found in the young, uncalcified bone matrix, or osteoid, which suggests its function is related to early bone development.
The presence of silicon is thought to assist in the stabilization of the bone matrix by facilitating the cross-linking of collagen fibers and proteoglycans. Studies have indicated that the mineral helps to regulate the deposition of calcium and phosphorus, influencing where and when these major minerals are incorporated into the bone. As bone tissue matures and calcification progresses, the concentration of silicon in the area tends to decline. Consuming bioavailable forms of silicon has been associated with greater bone mineral density, supporting the idea that it contributes to robust skeletal health.
Maintaining Healthy Connective Tissues
Beyond its function in bone, silicon is concentrated in various soft tissues, where it is instrumental in maintaining the integrity of connective structures. It supports the synthesis and structure of two major proteins: collagen and elastin. These proteins are fundamental for providing strength, flexibility, and elasticity to tissues throughout the body.
Silicon is highly concentrated in the skin, hair, nails, and arteries. In the skin, it helps support the structural framework that gives it elasticity and strength, and deficiencies may be linked to signs of premature aging. For hair and nails, the mineral contributes to strength and resilience, with inadequate levels potentially resulting in brittleness. By supporting the production of these key proteins, silicon helps ensure the proper function and appearance of these highly visible tissues.
Understanding Dietary Intake and Absorption
Humans obtain silicon through their diet, with the typical daily intake in Western populations ranging from 12 to 62 milligrams per day. Common food sources include whole grains, certain vegetables like green beans and bananas, and various beverages, including water and beer. The form in which silicon is consumed heavily influences how much the body can actually absorb.
The most readily absorbed form is orthosilicic acid (OSA), which is the monomeric, water-soluble state of the mineral. Absorption efficiency varies significantly across different sources; for instance, orthosilicic acid in alcohol-free beer and as a supplemental form has been shown to have a high absorption rate, sometimes exceeding 60% of the ingested dose. In contrast, solid foods and less soluble forms, such as colloidal silica, exhibit much lower absorption rates due to their chemical structure and tendency to polymerize in the gut. Once absorbed, the silicon travels in the bloodstream as orthosilicic acid before being utilized by tissues or excreted. Excess silicon that the body does not use is efficiently passed out of the body through the urine, with approximately 41% of ingested silicon being excreted.