Iron Deficiency Risk Calculator

Iron Deficiency Risk is estimated by adding up the lifestyle, dietary and medical factors that drain iron or block its absorption.
The score is this page’s own tally, not a validated clinical tool. It is meant to show which of your habits matter most.

Dietary intake plays a big role. People who eat red meat regularly get heme iron, which is absorbed at 15-35% efficiency.
Plant-based iron (non-heme) from spinach, lentils, and beans is absorbed at only 2-20% efficiency.
That gap is why the Dietary Reference Intakes set the iron need of vegetarians at 1.8 times the normal allowance.

Blood loss is the other big one. Menstruation is the largest routine drain in adults, which is why women aged 19 to 50 need about 18 mg of iron daily, against 8 mg for adult men.
Each whole-blood donation takes roughly 200 to 250 mg of iron with it, and stores can take months to rebuild, so regular donors run low more often than people expect.
Pregnancy raises the allowance to 27 mg, more than food alone usually supplies, and it is the commonest reason a young woman becomes deficient.

Absorption inhibitors reduce how much iron your body actually uses.
Coffee, tea, and calcium-rich foods consumed with meals can reduce iron absorption by up to 60%.
Celiac disease, inflammatory bowel disease, weight-loss surgery and long-term acid-blocking drugs all cut absorption too.

Absorption enhancers help your body use more iron.
Vitamin C (found in citrus fruits, bell peppers, and tomatoes) can increase non-heme iron absorption by 2-3 times.

Risk scoring, in full. Every factor and its exact weight:

Anything not in the table scores 0. A score of 0-2 is low risk, 3-5 moderate, and 6 or more high.

Sex is not scored on its own. What actually drains iron is blood loss, so menstruation carries that weight directly. A postmenopausal woman and an adult man have the same 8 mg daily allowance and, all else equal, the same risk from this list. The sex and age questions are there to get the recommended daily figure right, not to add points.

The heaviest pairing on the list is a vegan diet plus heavy periods, 6 points before anything else is counted. That combination alone puts you in the high band, and it should: it is by some distance the most common presentation of iron deficiency in adults.

What the blood test means. Only a ferritin test shows where your iron stores actually are, and a normal hemoglobin does not rule out depleted stores.
The World Health Organization reads ferritin under 15 ng/mL as deficiency in adults. Many doctors treat anything under 30 as low stores, and the American Gastroenterological Association uses 45 when anemia is already present.