Iron

Iron is the nutrient where I'm most insistent about testing first, because getting it wrong in either direction causes real harm.

Read this first

Never start an iron supplement without a blood test. Too much iron is genuinely harmful, the symptoms of low iron overlap with a dozen other things, and accidental iron overdose is a leading cause of poisoning death in young children. Get your ferritin checked by your doctor.

Mixed greens and spinach topped with pomegranate seeds, berries, sliced almonds and crumbled cheese. — Greens with pomegranate, berries and almonds

What it does

Iron sits at the centre of haemoglobin, the protein that carries oxygen around your body. Run short and less oxygen gets delivered — which is why the symptoms are what they are.

What running low feels like

Tiredness that sleep doesn't fix. Breathlessness on stairs you used to manage. Cold hands and feet. Poor concentration. Sometimes hair shedding, brittle nails, or unusual cravings for ice.

All of those have other explanations too, which is exactly why guessing is a bad idea.

Two kinds of dietary iron

Heme iron — from meat, fish and poultry. Absorbed efficiently, roughly 15–35% of what you eat.

Non-heme iron — from lentils, beans, tofu, dark leafy greens, fortified grains, pumpkin seeds. Absorbed far less efficiently, perhaps 2–20%, and much more affected by what else is on the plate.

Making non-heme iron work harder

Vitamin C alongside substantially increases absorption. Lentils with tomatoes and peppers; spinach with a squeeze of lemon. This is why so many traditional dishes pair beans with something acidic — nobody planned it, it just worked.
Tea and coffee with meals reduce it. The tannins bind iron. Move your tea to between meals rather than with them.
Calcium competes. A large dairy serving at the same meal reduces iron absorption somewhat.
Cast iron pans genuinely add a small amount, particularly with acidic foods.

Who tends to run short

People who menstruate, especially with heavy periods. Pregnant women. Endurance athletes. People who eat little or no meat. Anyone with a condition affecting absorption, including coeliac disease.

If a supplement is warranted

That's a decision made with your doctor, with your ferritin result in front of you. If it is: gentler forms like bisglycinate tend to cause less digestive upset than sulphate, taking it with vitamin C helps, and taking it every other day may actually absorb better than daily. Constipation is common. Retest after a few months rather than staying on it indefinitely.

A reminder

This is general nutrition education, not medical advice, and it isn't intended to diagnose, treat, cure or prevent any condition. If you're pregnant or breastfeeding, taking medication, or managing a diagnosed condition, talk to your doctor or pharmacist before making changes.

Written by Mellissa Wallace, Registered Holistic Nutritionist, Okanagan BC.

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