Vitamin C (ascorbic acid)

Research records

Historical source snapshot. Not freshly verified, not a recommendation. Study findings, community accounts and app defaults are not interchangeable.

Publication suitability · 2026-10-15: Historical reference only; not a clinical verification. Clinical, regulatory, efficacy, safety and dose claims are not independently established by this review.

Vitamin C (ascorbic acid)

Water-soluble antioxidant vitamin. Absorption saturates, so split dosing beats one large dose.

Evidence category: Clinical study. This describes the source category, not approval or certainty.

Regulatory statement in source: Not separately recorded; do not infer approval from the evidence category.

Small human studies show that vitamin C absorption in the gut saturates: beyond a point, taking more does not raise absorption in proportion. In an intestinal perfusion study in volunteers, absorption followed saturation kinetics, and the authors suggested very large single doses are absorbed less efficiently than smaller ones taken separately. In a four-person comparison of oral forms, about 30% of a large oral dose was recovered in urine against about 85% after injection, with a timed-release capsule lower still, and absorption varied widely between people. The NIH fact sheet is a general reference.

Benefits reported in the imported source

• Small human studies show gut absorption saturates, so spread intake is absorbed more efficiently.
• The NIH fact sheet serves as a general reference on the vitamin.

Risks and limits

• The absorption studies are tiny, one with four people, and absorption varied widely.
• Much of a large oral amount ends up in urine, and a timed-release capsule fared worst.
• The sources here test absorption only, not any health outcome.

Source bottom line: The evidence here covers absorption only: uptake saturates and varies between people, with no outcomes tested.

Uncertainty: Reference information only. Not medical advice.

Study protocols — reports, not instructions

Community and practice descriptions

Accounts of a practice are not evidence of safety or effectiveness. Words such as “standard”, “safe” or “recommended” describe the source account, not verified consensus or this wiki’s advice. Commercial and self-published citations are retained for traceability, not vendor endorsement or independent clinical corroboration.

Pharmacokinetic context

Historical half-life estimate: 2 hours. Dhotre et al. 2025, Pharmaceutics, PMID 41304796 — acute plasma disappearance; the separate, slower body-pool depletion kinetics relevant to scurvy risk operate over weeks and are a different process Population/route context and estimates may differ. This is not a schedule or a verified human dosing rule.

Source references

• Vitamin C - Health Professional Fact Sheet (availability check 2026-10-15: source not retrieved; HTTP 403)
• Demonstration of saturation kinetics in the intestinal absorption of vitamin C in man and the guinea pig (Nelson et al. 1978)
• Ascorbic acid absorption in humans: a comparison among several dosage forms (Yung et al. 1982)
• NIH ODS: Vitamin C (availability check 2026-10-15: source not retrieved; HTTP 403)