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Moderate evidenceJoints & skin

Orthosilicic Acid (ch-OSA)

A bioavailable form of silicon with several small randomized trials on hair, nails, skin and bone markers. The effects are real but modest, and nearly all the trials come from the same manufacturer.

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What the science says

  • Skin, hair and nails Moderate evidence

    A randomized placebo-controlled trial in women with photodamaged skin found improvements in skin roughness and elasticity and in nail and hair brittleness over 20 weeks. A second randomized trial in women with fine hair reported increased hair tensile strength and changes in hair morphology after 9 months.

  • Bone formation markers Limited evidence

    A randomized placebo-controlled trial in osteopenic women found that ch-OSA added to calcium and vitamin D stimulated markers of bone formation. The trial measured biochemical markers and partial bone density changes, not fractures.

  • Knee osteoarthritis Limited evidence

    A 12-week randomized, double-blind, placebo-controlled multicentre trial in 166 patients found no effect of ch-OSA on the primary outcome, WOMAC pain, in the group overall. A benefit appeared only in the male subgroup, which is a post-hoc style finding that needs confirmation.

Dosage & safety

Studied doseStudied doses are 5–10 mg of silicon per day as choline-stabilized orthosilicic acid, taken for 20 weeks to 12 months. Effects on hair and nails take months to appear.
SafetyWell tolerated in trials lasting up to a year, with no significant adverse effects reported. Silicon is poorly absorbed and excreted by the kidneys, so people with significant kidney impairment should be cautious. Not studied in pregnancy or children.

How to take it

TimingTiming does not matter.
With food?With or without food; dilute the liquid concentrate in water or juice before drinking, as it is acidic.
Worth knowingHair and nail changes need four to five months to show, because you are only seeing newly grown tissue — judging it at six weeks tells you nothing.

Frequently asked questions

Does orthosilicic acid improve hair, skin and nails?

Orthosilicic acid (ch-OSA) has moderate evidence: a placebo-controlled trial found improved skin roughness, elasticity and nail and hair brittleness over 20 weeks, and another found stronger hair after 9 months. The effects are modest and nearly all trials come from the same manufacturer.

How long does orthosilicic acid take to work?

Hair and nail changes from orthosilicic acid need four to five months to show, because you only see newly grown tissue. Studied doses are 5–10 mg of silicon per day as choline-stabilised orthosilicic acid.

Does orthosilicic acid help bones or arthritis?

Orthosilicic acid has limited evidence for bone: it raised bone formation markers in osteopenic women, but fractures were not measured. In a 12-week trial in 166 knee osteoarthritis patients, ch-OSA had no effect on pain overall.

Is orthosilicic acid safe?

Orthosilicic acid was well tolerated in trials lasting up to a year, with no significant adverse effects. Silicon is excreted by the kidneys, so be cautious with kidney impairment, and dilute the acidic liquid in water or juice.

Scientific references

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