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ING-087Ingredient Research Profile

Vitamins

Vitamin C (Ascorbic Acid)

Also known as: Ascorbic acid · L-ascorbate · Sodium ascorbate

●●●Strong Evidence

Essential for collagen synthesis, immune function, and iron absorption. Humans cannot synthesise vitamin C endogenously — dietary and supplemental intake is mandatory.

Effective Dose

500–1000mg / day

per clinical evidence

Evidence Level

Strong

Vitamins

Mechanism

Collagen hydroxylation co-factor, antioxidant, immune modulation

primary action

Best For

Immune health

Collagen synthesis, Iron absorption, Antioxidant

This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.

What Is Vitamin C (Ascorbic Acid)?

Vitamin C is a water-soluble vitamin and powerful antioxidant required for collagen hydroxylation, carnitine biosynthesis, and catecholamine synthesis. Unlike most mammals, humans lack the enzyme (L-gulonolactone oxidase) needed to synthesise it endogenously. Athletes have elevated needs due to increased oxidative stress.

How It Works: The Science

Vitamin C is a co-factor for prolyl and lysyl hydroxylase enzymes, which add hydroxyl groups to proline and lysine in procollagen — a critical step for collagen triple-helix stability and cross-linking. As an antioxidant, ascorbate donates electrons to neutralise ROS and regenerates vitamin E from its oxidised form.

Primary Mechanism

Collagen hydroxylation co-factor, antioxidant, immune modulation

Evidence-Based Benefits

Reduces duration and severity of common cold

moderate

Hemilä & Chalker (2013) Cochrane review — 1g/day reduced cold duration by 8% in adults

Essential for collagen synthesis and wound healing

strong

Co-factor for prolyl/lysyl hydroxylase — deficiency causes scurvy within weeks

Enhances non-haem iron absorption

strong

100mg with a meal increases plant-based iron absorption 2–4×

Reduces exercise-induced oxidative stress

moderate

Multiple RCTs — significant reductions in lipid peroxidation markers at 1g/day

Dosage Guide

Effective Dose

500–1000mg / day

500–1000mg/day for athletes. Absorption is saturable — doses above 1g offer diminishing returns. Spread across 2 doses for sustained plasma levels. Buffered forms (calcium ascorbate) gentler on the stomach.

Safety Profile & Side Effects

Very safe. High doses (>2g/day) may cause GI distress and loose stools. Can increase oxalate excretion — relevant for those prone to kidney stones. Avoid megadosing around training (may blunt ROS-driven adaptations).

Who Should (and Shouldn't) Take It

Best for
Immune healthCollagen synthesisIron absorptionAntioxidant
Who it's for

Essentially everyone — inadequate intake is common. Athletes, smokers (2× the RDA recommended), and those eating low fruit/vegetable diets benefit most. Pair with collagen peptides (1 hour pre-exercise) for tendon synthesis.

Frequently Asked Questions

What is the recommended dose of Vitamin C (Ascorbic Acid)?

500–1000mg/day for athletes. Absorption is saturable — doses above 1g offer diminishing returns. Spread across 2 doses for sustained plasma levels. Buffered forms (calcium ascorbate) gentler on the stomach.

Is Vitamin C (Ascorbic Acid) safe?

Very safe. High doses (>2g/day) may cause GI distress and loose stools. Can increase oxalate excretion — relevant for those prone to kidney stones. Avoid megadosing around training (may blunt ROS-driven adaptations).

How does Vitamin C (Ascorbic Acid) work?

Vitamin C is a co-factor for prolyl and lysyl hydroxylase enzymes, which add hydroxyl groups to proline and lysine in procollagen — a critical step for collagen triple-helix stability and cross-linking. As an antioxidant, ascorbate donates electrons to neutralise ROS and regenerates vitamin E from its oxidised form.

Who should take Vitamin C (Ascorbic Acid)?

Essentially everyone — inadequate intake is common. Athletes, smokers (2× the RDA recommended), and those eating low fruit/vegetable diets benefit most. Pair with collagen peptides (1 hour pre-exercise) for tendon synthesis.

Related Ingredients

Collagen Peptides (Type I/III)Zinc (Bisglycinate / Picolinate)Iron (Ferrous Bisglycinate)N-Acetyl Cysteine (NAC)

Medical Disclaimer

Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →