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Silica supplement
Trace Mineral

Silica: Benefits, Dosage, Forms & Research

Trace Mineral

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

TL;DR — Quick Answer

Silica supports collagen production, bone density, and hair/nail strength. Choline-stabilized orthosilicic acid (ch-OSA, sold as BioSil) is the best-studied form at 6-10mg daily. A 2005 RCT showed it improved skin elasticity and hair/nail brittleness after 20 weeks.

Key Facts

What it is
A trace mineral supporting collagen synthesis and connective tissue integrity
Primary benefits
  • Supports collagen production in skin
  • May improve hair thickness and nail strength
  • Contributes to bone mineralization
  • Maintains connective tissue elasticity
Typical dosage
6-10mg orthosilicic acid daily (or 20-40mg as horsetail extract)
Evidence level
Emerging
Safety profile
Generally Safe

What the Research Says

Silicon/silica research for supplementation is still emerging. The strongest evidence comes from the Barel et al. (2005) double-blind RCT showing ch-OSA improved skin, hair, and nails over 20 weeks. Epidemiological data is supportive: the Framingham Offspring study (Jugdaohsingh et al., 2004, n=2,847) found a strong positive association between dietary silicon intake and bone mineral density, with the highest silicon quartile having significantly higher hip BMD than the lowest. However, interventional trials on bone density are limited. Reffitt et al. (2003) showed orthosilicic acid stimulated collagen type I synthesis in human osteoblasts in vitro, providing mechanistic support.

Benefits of Silica

  • Skin health — Barel et al. (2005, n=50, RCT) found choline-stabilized orthosilicic acid (ch-OSA) at 10mg daily for 20 weeks significantly improved skin elasticity and reduced wrinkle depth compared to placebo
  • Hair and nail quality — the same Barel et al. study showed ch-OSA significantly reduced hair brittleness and improved nail hardness after 20 weeks of supplementation
  • Bone density — the Framingham Offspring cohort (Jugdaohsingh et al., 2004, n=2,847) found that higher dietary silicon intake was associated with significantly higher bone mineral density at the hip, particularly in premenopausal women
  • Collagen synthesis — silicon is involved in the hydroxylation of proline, a key step in collagen cross-linking and maturation; it activates prolyl hydroxylase enzymes
  • Arterial health — silicon is found in high concentrations in arterial walls and may help maintain vascular elasticity with aging
Did you know?

Silicon/silica research for supplementation is still emerging.

Forms of Silica

FormBioavailabilityBest For
Choline-Stabilized Orthosilicic Acid (ch-OSA / BioSil)HighBest-studied and most bioavailable form — directly provides absorbable silicon
Horsetail Extract (Equisetum arvense)Low-ModerateTraditional herbal source of silica — variable silicon content and absorption
Colloidal SilicaLowCommonly marketed but poorly absorbed — large particle size limits bioavailability
Bamboo ExtractLow-ModeratePlant-based silica source with high silicon content but limited absorption data

Dosage Recommendations

General recommendation: 6-10mg orthosilicic acid daily; or 20-40mg silicon from horsetail extract

Timing: With or without food; consistent daily use for at least 12-20 weeks needed for visible results

Dosage by Condition

ConditionRecommended DoseEvidence
Skin elasticity10mg ch-OSA daily for 20+ weeksEmerging
Hair and nail health6-10mg ch-OSA dailyEmerging
Bone density support6-12mg bioavailable silicon dailyEmerging

Upper limit: No established UL; doses up to 50mg silicon daily appear safe in studies

Side Effects and Safety

Safety profile: Generally Safe

Potential Side Effects

  • Generally very well-tolerated
  • Mild digestive discomfort (rare)
  • Long-term high-dose silica from horsetail extract may contain thiaminase (destroys vitamin B1)
  • Kidney stones theoretically possible with very high chronic silica intake, though not documented at supplement doses

Drug & Supplement Interactions

  • Horsetail extract may have diuretic effects — caution with diuretic medications
  • Thiaminase in horsetail may deplete vitamin B1 with chronic use — consider B1 supplementation
  • No significant interactions reported with ch-OSA (BioSil) form
Check Silica interactions with other supplements →
BenefitsDosage GuideSide EffectsTypes & FormsResearchFAQ

Related Conditions

Skin Health

Related Supplements

CollagenVitamin B7 (Biotin)Vitamin C

Frequently Asked Questions

What is the best form of silica to take?

Choline-stabilized orthosilicic acid (ch-OSA, marketed as BioSil) is the best-studied and most bioavailable form. It provides silicon in a directly absorbable form. Horsetail extract is a traditional alternative but has variable silicon content and lower bioavailability. Colloidal silica (large particle) is poorly absorbed and not recommended.

How long does silica take to work for hair and nails?

The landmark Barel et al. study showed significant improvements in hair brittleness and nail hardness after 20 weeks (about 5 months) of daily ch-OSA supplementation. This timeframe aligns with hair and nail growth cycles. Expect to take silica consistently for at least 3-6 months before judging results.

Is silica the same as silicon?

Not exactly. Silicon (Si) is the element, while silica (SiO2, silicon dioxide) is the most common compound of silicon found in nature. In supplement form, orthosilicic acid [Si(OH)4] is the bioavailable species that the body can actually absorb and use. When people say "silica supplement," they typically mean a product providing bioavailable silicon.

References

  1. (). Effect of oral intake of choline-stabilized orthosilicic acid on skin, nails and hair in women with photodamaged skin. Archives of Dermatological Research. DOI
  2. (). Dietary silicon intake is positively associated with bone mineral density in men and premenopausal women of the Framingham Offspring cohort. Journal of Bone and Mineral Research. DOI
  3. (). Orthosilicic acid stimulates collagen type 1 synthesis and osteoblastic differentiation in human osteoblast-like cells in vitro. Bone. DOI