Vitamin C
Also known as Ascorbic acid
Vitamin C is a water-soluble antioxidant essential for collagen synthesis, immune function, and the regeneration of other antioxidants. It also dramatically improves absorption of plant-based (non-heme) iron.
Benefits
Boosts iron absorption
StrongConverts non-heme iron to a form the gut absorbs far more readily.
Supports collagen and skin
StrongA required cofactor for collagen synthesis and skin repair.
Immune support
ModerateMay modestly reduce the duration of colds with regular intake.
Pros & cons
Pros
- Cheap and very safe
- Strong synergy with iron
- Water-soluble, low toxicity
Cons
- Excess is excreted, not stored
- Megadoses offer little extra benefit
Side effects
GI upset at high doses
Doses above ~1,000 mg can cause loose stools.
How to take it
Typical dose
200–1,000 mg per day
Timing
With iron-rich meals to maximize iron uptake
Common forms
What the research says
Vitamin C and iron absorption
StrongCo-ingestion markedly increases non-heme iron absorption in controlled studies.
Vitamin C and the common cold
ModerateRegular supplementation modestly shortens cold duration but does not reliably prevent colds.
How it connects
Relationships between Vitamin C and other supplements in the matrix.
Taken together, vitamin C can multiply the absorption of plant-based iron.
Compare the pairing