Dietary iron comes in two forms, heme and non heme iron. But what is the difference between them, and what (if any) changes do I need to make to my diet to ensure that I get enough Iron when I am a vegan?
What Is Heme Iron?
Heme iron is formed when the iron combines with certain proteins only found in other animals. This means that iron in it’s heme form can only be found in meat, seafood and poultry. That is not to say that all iron in animals are heme (It makes up about 40%, 60% being non heme iron). Heme iron has much better absorption rates than non heme iron, at around 15 – 35% of the amount actually ingested.
What Is Non Heme Iron?
Non Heme iron makes up approximately 60% of the iron in meat, and all iron in plants. Non heme iron has a much lower absorption rate than heme iron, sitting just above half that of heme iron. Because of this, the recommended daily intake of iron is usually described as 1.8x the normal rate of a meat eater. Iron absorption is markedly increased by eating foods containing Vitamin C, in some studies this has shown to increase non heme iron absorption six-fold. Making the absorption rate as good or better than heme iron alone.
Do I Need Heme Iron?
No. While the absorption rates are lower for non heme iron, the human body does not have a reliance on heme iron to survive. A vegan can get all the iron he or she needs from non heme iron alone.
Are Iron Supplements Heme or Non Heme Iron?
Most iron supplements (but not all) are completely vegan friendly and are made from non heme iron. Simply check the label as the bottles are usually well marked.
Recommended Daily Allowances
These numbers are omnivore based. Because of the lower absorption rates of non heme iron, vegans/vegetarians should look to take 1.8 times that of the numbers shown.
|Birth to 6 months||0.27 mg||0.27 mg|
|7–12 months||11 mg||11 mg|
|1–3 years||7 mg||7 mg|
|4–8 years||10 mg||10 mg|
|9–13 years||8 mg||8 mg|
|14–18 years||11 mg||15 mg||27 mg||10 mg|
|19–50 years||8 mg||18 mg||27 mg||9 mg|
|51+ years||8 mg||8 mg|
Chart Source : http://ods.od.nih.gov