Iron and the HFE gene
What the HFE C282Y and H63D variants mean for iron absorption, how often C282Y homozygotes actually develop iron overload, and which diet changes matter.
The short answer
Two copies of the HFE C282Y variant (rs1800562) cause most cases of hereditary hemochromatosis, where the body absorbs too much iron. It affects roughly 1 in 200 to 400 people in the US, Europe and Australia, mostly of northern European descent. Many people with two copies never develop iron overload disease. If you have them, the useful step is a blood test, and the main diet changes are skipping iron and vitamin C supplements and going easy on alcohol.
How common it is, and how often it causes harm
Hereditary hemochromatosis is the most common inherited disorder in people of northern European ancestry, at about 1 in 200 to 400 people, with the highest rates in people of Irish and Scandinavian descent. It is rare in Asian, African, Hispanic and Pacific Islander populations. Penetrance is low and variable: many C282Y homozygotes never develop symptoms, and organ damage occurs in a minority.1
| Your HFE result | What it means |
|---|---|
| C282Y / C282Y | The main genetic form of hemochromatosis. Ask a clinician about ferritin and transferrin saturation tests. |
| C282Y / H63D | Usually a mild effect on iron. Worth mentioning to a clinician, especially with other liver risks. |
| One C282Y or H63D | Carrier. Iron overload from HFE alone is unlikely. |
What actually changes with diet
Treatment for iron overload is removing blood, and diet plays a supporting role. The NIDDK advises people with hemochromatosis that doctors may recommend avoiding iron supplements, avoiding vitamin C supplements (which increase iron absorption), cutting back on alcohol and avoiding raw or undercooked shellfish, which can cause serious infections in people with liver disease.2 A 2021 evidence review notes that, apart from alcohol, dietary changes have minimal impact on iron overload, while limiting iron-rich foods may reduce how much blood needs removing.1
What GenomEats suggests for C282Y homozygotes
- Get an iron panel before changing anything else.
- Skip iron supplements and iron-containing multivitamins unless a clinician prescribes them.
- Skip high-dose vitamin C supplements, especially with meals.
- Keep alcohol low, and avoid raw oysters and other raw shellfish.
Sources
- Kane SF, Roberts C, Paulus R. Hereditary hemochromatosis: rapid evidence review. Am Fam Physician. 2021;104(3):263–270. www.aafp.org
- National Institute of Diabetes and Digestive and Kidney Diseases. Eating, diet, and nutrition for hemochromatosis. www.niddk.nih.gov
This page is educational and does not diagnose or treat any condition. Talk to a qualified clinician before making medical decisions based on a genetic result.