Silicon is the second most abundant element in the Earth's crust — found in sand, rock, quartz crystals, and the soil from which all plant life grows. It is also, increasingly, recognized as an essential trace element in human biology: critical for collagen formation, bone density, arterial wall integrity, neurological health, and the very connective tissue — fascia — that holds the body together. Yet it remains almost entirely absent from standard nutritional discussions.
Silicon in Biology: From Earth to Body
Silicon (Si) enters the human food chain through plants that absorb it from the soil as orthosilicic acid (OSA) — the biologically active, water-soluble form. In its elemental form, silicon is not bioavailable; it is only when bound to water as silicic acid (Si(OH)₄) that the body can absorb and utilize it.
The human body contains approximately 7 grams of silicon — distributed primarily in connective tissues, bone, skin, hair, nails, and the aortic wall. Silicon concentrations are highest in tissues that are metabolically most active in structural maintenance: the connective tissue matrix, including the fascial system, periosteum, and arterial walls.
Crucially, silicon concentration in tissues declines dramatically with age. In skin and arteries, silicon levels in people over 60 can be as low as 20% of levels in young adults — a decline that correlates with the well-known age-related decreases in skin elasticity, collagen density, bone mineral quality, and arterial compliance.
Collagen & Silicon Research
Carlisle (1976, 1981) — Edith Carlisle at UCLA conducted foundational research showing that silicon-deficient animals developed abnormal skull and limb bone structure and reduced collagen content. Her work established silicon as essential for collagen cross-linking — the molecular scaffolding that gives connective tissue its tensile strength. Without adequate silicon, collagen molecules cannot form their characteristic triple-helix structures effectively.
The Fascial Connection: Silicon and the Body's Living Web
The fascial system — the continuous web of connective tissue described in the Human Garage article — is composed primarily of collagen and elastin fibers embedded in a water-rich gel called the extracellular matrix (ECM). Silicon is a critical co-factor in both collagen synthesis and the maintenance of the ECM's hydration and electrical properties.
Research has shown that orthosilicic acid stimulates collagen synthesis in osteoblasts, fibroblasts, and chondrocytes — the cells responsible for bone, fascia, and cartilage production respectively. Silicon also appears to influence glycosaminoglycan synthesis — the compounds responsible for the gel-like hydration of the ECM. In other words, silicon is not just a structural component but an active regulator of the body's connective tissue intelligence.
Bone Density Research
Macdonald et al. (2012) — The Framingham Offspring Cohort Study analyzed silicon intake in 2,847 adults and found that men with higher dietary silicon intake had significantly higher cortical bone density at the hip. A 2004 double-blind trial found that women supplementing with orthosilicic acid showed significantly increased procollagen type I (a collagen precursor) and osteocalcin — markers of bone formation activity — compared to placebo.
— Dr. Klaus Kaufmann, Silicon Researcher
Ancient Wisdom: Silicon in Traditional Medicine
While silicon as a named element is a modern discovery (1824), the plants and minerals richest in silica have been central to healing traditions worldwide for millennia. The silica-rich plants used most prominently in traditional medicine include:
Horsetail (Equisetum arvense)
The most silicon-dense plant known to science (containing up to 25% silica by dry weight), horsetail has been used in European folk medicine since antiquity for strengthening bones, hair, skin, and nails — all silicon-dependent tissues. Nicholas Culpeper's 17th-century herbal describes it for "consolidating broken bones." Modern analysis confirms it contains silicic acid in a partially bioavailable form.
Bamboo
Bamboo tabasheer — the silica-rich concretion that forms inside bamboo joints — has been used in Ayurvedic medicine (called vanshalochan) for over 2,000 years to strengthen bones, treat respiratory conditions, and enhance reproductive health. Bamboo is one of the highest plant sources of silica, and bamboo extract is now widely used in supplements.
Ayurvedic Tradition
Vanshalochan (bamboo silica) is classified in Ayurveda as a rasayana — a rejuvenating substance that promotes longevity, vitality, and tissue strength. It is traditionally combined with ashwagandha and shatavari as a bone and reproductive tonic. The Charaka Samhita (c. 300 BCE) specifically references its application for strengthening the skeletal system and for conditions of debility — aligning precisely with silicon's modern-understood role in collagen and bone matrix formation.
Diatomaceous Earth and Clay
Geophagy — the intentional eating of clay — has been documented in cultures on every inhabited continent. While often explained as meeting mineral needs during pregnancy or illness, clay consumption provides highly bioavailable silica alongside other minerals. Bentonite and montmorillonite clays are now widely used in wellness protocols for their silica content, adsorptive properties, and alkalizing effect.
Silicon and the Brain: An Emerging Connection
Perhaps the most surprising emerging area of silicon research involves neurological health. Silicon has been detected in the brain's connective tissues and cerebrospinal fluid, and several studies have begun to examine its relationship to aluminum accumulation — a factor implicated in neurodegenerative disease.
Silicic acid appears to reduce aluminum absorption from the gut and may facilitate aluminum excretion from the body. Research by Exley et al. (2013) found that drinking silicon-rich mineral water significantly increased urinary aluminum excretion in Alzheimer's disease patients — along with improvements in cognitive function — raising the possibility that silicon deficiency may be a contributing factor in aluminum-linked neurodegeneration.
Skin & Hair Research
A 12-week double-blind trial (Barel et al., 2005) in women with fine hair found that oral orthosilicic acid supplementation produced significant improvement in hair tensile strength and thickness, as well as skin surface evaluation scores. Silicon is a cofactor in the formation of keratin — the structural protein of hair and nails — explaining these cosmetic effects through basic biochemistry rather than marketing claims.
Food Sources and Supplementation
The richest dietary sources of silicon include: unrefined whole grains (oats, millet, barley — especially their bran layers), root vegetables (beets, parsnips, potatoes), green beans and leafy greens, horsetail tea, and beer (fermented grains are surprisingly high in bioavailable silicon — explaining, perhaps, some unexpected health associations with moderate beer consumption in epidemiological studies).
Modern food processing dramatically reduces silicon intake: refined white flour contains about 10% of the silicon of whole wheat flour. The shift to processed foods over the past century has coincided with silicon depletion from both soil and diet.
How to Increase Silicon Naturally
Horsetail tea: 1–2 cups daily of horsetail infusion is one of the most economical silicon sources. Whole grains: Switch white rice and flour to millet, oats, and barley — all significantly higher in silica. Silica-rich mineral water: Several natural spring waters (Volvic, Fiji, Spritzer) contain high levels of orthosilicic acid — the most bioavailable form. Bamboo extract supplements: Standardized bamboo silica supplements are widely available and well-researched. Diatomaceous earth (food grade): 1 teaspoon in water daily provides concentrated silica — start slowly to assess tolerance.
References
- Carlisle EM. (1981). Silicon: a requirement in bone formation independent of vitamin D. Calcified Tissue International, 33(1), 27–34.
- Macdonald HM, et al. (2012). Dietary silicon intake is associated with bone mineral density in premenopausal women. Journal of Bone and Mineral Research, 27(1), 37–44.
- Barel A, et al. (2005). Effect of oral intake of choline-stabilized orthosilicic acid on skin, nails and hair. Archives of Dermatological Research, 297(4), 147–153.
- Exley C, et al. (2013). Non-invasive therapy to reduce the body burden of aluminium in Alzheimer's disease. Journal of Alzheimer's Disease, 35(1), 197–214.
- Price CT, et al. (2013). Silicon: a review of its potential role in the prevention and treatment of postmenopausal osteoporosis. International Journal of Endocrinology.