Iron Absorption
Iron (Bisglycinate) + Vitamin C
Vitamin C converts iron to its better-absorbed ferrous form — the cleanest absorption-boost synergy in supplement biology.
Mineral
Highly absorbable iron form that's gentle on the stomach. Best choice for those who experience GI upset with other iron forms.
Full Iron (Bisglycinate) profile →Vitamin
Vitamin C is an essential water-soluble antioxidant required for collagen synthesis, immune function, and iron absorption. Calcium ascorbate is a buffered form that reduces gastric irritation.
Full Vitamin C profile →Why they work together
Non-heme iron (the form in plant foods and most iron supplements) is absorbed better in the ferrous (Fe²⁺) state. Vitamin C reduces the ferric form (Fe³⁺) to ferrous in the stomach, often doubling or tripling iron absorption in meta-analyses. This is why pomegranate juice and orange juice with iron-rich meals is folk nutrition that actually holds up to RCT scrutiny. The pairing is equally useful for supplemental iron (especially in menstruating women, vegetarians, or diagnosed iron deficiency) and for dietary iron at meals.
How to dose them
Take 100–250 mg vitamin C at the same time as your iron supplement (or with iron-rich meals if getting iron from food). The vitamin C needs to be present in the stomach with the iron, not hours apart. Works with any vitamin C form (ascorbic acid is fine).
Evidence
Well-established — multiple trials spanning decades show 2–4× absorption gains for non-heme iron when vitamin C is co-administered at 100+ mg. It's the default pairing recommendation in hematology practice.
Watch-outs
Avoid coffee, tea, or calcium supplements within 2 hours of iron — polyphenols and calcium block iron absorption, canceling the vitamin C boost. Vitamin C + iron at very high doses can stress users with hemochromatosis; iron overload is the main safety concern.
Next steps
Educational only. Synergy pairs are not prescriptions. Run any new supplement combination past your clinician if you take prescription medication.