Written by the Vegums pharmacist team | Vegan Society Certified | Updated April 2026
Key Takeaways
- Women need 14.8mg of iron daily; men and post-menopausal women need 8.7mg
- Plant-based iron (non-haem) is less easily absorbed — pair with vitamin C to boost absorption by up to 3x
- Vegans and vegetarians are at higher risk of iron deficiency due to diet alone
Iron deficiency is the most common nutritional deficiency in the world — and if you're vegan, you're statistically more likely to be affected. But here's what most articles don't tell you: it's not because a vegan diet is inadequate. It's because plant-based iron works differently to animal-based iron, and most people — including many GPs — don't fully understand the distinction.
This guide explains exactly how iron works on a vegan diet, what deficiency actually looks like, and what to do about it. Written by our team of registered pharmacists, it's the resource we wish existed when we founded Vegums.
Why Vegans and Plant-Based Iron Work Differently
Iron in food comes in two forms: haem iron (found in meat and fish) and non-haem iron (found in plants). The difference matters enormously.
Haem iron is absorbed efficiently by the gut — roughly 14–18% of what you eat makes it into your bloodstream. Non-haem iron, the only form available from plant sources, has a much lower baseline absorption rate: 3–8%, depending on what else you eat alongside it.
This is why the UK's NHS recommends that vegans aim for approximately 1.8 times the standard iron intake. In practical terms:
- Women aged 19–50: 32mg/day (vs 14.8mg for omnivores)
- Men and post-menopausal women: 14mg/day (vs 8.7mg for omnivores)
Getting 32mg of iron from kale, lentils, and tofu every single day is genuinely difficult — which is exactly why iron deficiency is so common among vegan women, and why supplementation is often the sensible choice.
Signs of Iron Deficiency in Vegans
Iron deficiency develops gradually, which is why it's often missed. By the time your GP diagnoses iron deficiency anaemia, your ferritin (iron stores) have usually been low for months.
The most common early symptoms include:
- Persistent fatigue — the kind that doesn't improve with sleep
- Breathlessness doing tasks that shouldn't wind you
- Brain fog — difficulty concentrating or remembering things
- Pale skin — particularly noticeable on the inside of the lower eyelid
- Cold hands and feet — poor oxygen delivery to extremities
- Brittle nails — particularly nails that curve downward (koilonychia)
- Hair loss or hair that feels thin and fragile
- Headaches — especially on exertion
- Heart palpitations — particularly during exercise
- Restless legs — an uncomfortable urge to move the legs, especially at night
Pharmacist note: Many of these symptoms overlap with B12 and vitamin D deficiency, which are also common in vegans. If you're experiencing fatigue, brain fog, or breathlessness, it's worth testing all three — not just iron. Your GP can order a full blood count, serum ferritin, B12 and vitamin D test in one appointment.
Best Plant-Based Food Sources of Iron
Before turning to supplements, it's worth knowing which plant foods deliver meaningful iron — and crucially, what to eat alongside them.
Higher-iron plant foods (per 100g, approximate):
| Food | Iron (mg) |
|---|---|
| Cooked lentils | 3.3mg |
| Firm tofu | 5.4mg |
| Cooked chickpeas | 2.9mg |
| Pumpkin seeds | 8.8mg |
| Cooked spinach | 3.6mg |
| Dark chocolate (85%+) | 11.9mg |
| Dried apricots | 2.7mg |
| Fortified breakfast cereal | Up to 12mg |
| Cooked kidney beans | 2.5mg |
| Quinoa | 1.5mg |
The key to absorbing plant iron well is pairing it with vitamin C. Ascorbic acid converts non-haem iron into a more soluble form that the gut absorbs far more efficiently. A glass of orange juice with your lentil soup, red peppers in your chickpea curry, or a kiwi alongside your fortified cereal — these simple combinations can significantly improve iron absorption.
Equally important: what to avoid alongside iron-rich foods
- Tea and coffee (tannins bind to iron and reduce absorption by up to 60%)
- Calcium-rich foods eaten at the same time
- Foods high in phytates (though soaking, sprouting and fermenting legumes helps)
When Food Isn't Enough: Do You Need an Iron Supplement?
For many vegans, particularly women of reproductive age, diet alone cannot reliably meet iron needs. Here are the situations where supplementation is strongly worth considering:
- You have heavy periods — blood loss increases iron requirements significantly
- You're pregnant or planning to become pregnant — iron demand increases substantially in the second and third trimesters
- You're an endurance athlete — exercise increases iron turnover
- You've already been told your ferritin is low — food changes alone are usually too slow to restore stores
- You eat a relatively limited plant-based diet — not everyone eats iron-rich foods consistently
- You've been vegan for less than a year — body stores can deplete faster than expected, especially transitioning from a meat-heavy diet
If you fall into any of these categories, discussing supplementation with your GP or pharmacist is sensible. You don't need to wait until you're anaemic — low ferritin alone is enough to cause the symptoms listed above.
What to Look for in a Vegan Iron Supplement
Not all iron supplements are equal. As pharmacists, these are the factors we look for:
1. The Form of Iron
The most important factor. Different iron salts have dramatically different tolerability and absorption profiles:
- Ferrous fumarate — commonly prescribed by GPs; high absorption but often causes constipation and stomach cramps
- Ferrous sulphate — very cheap, widely available; absorption is reasonable but gut side effects are frequent
- Ferrous bisglycinate (iron bisglycinate) — chelated iron with excellent absorption and significantly better tolerability; far less likely to cause constipation
- Ferric forms — generally lower absorption than ferrous forms
Our recommendation: Ferrous bisglycinate is typically the best choice for supplementing. It's the form we chose for Vegums Super Iron Gummies.
2. Added Vitamin C
Look for supplements that include vitamin C. It enhances absorption of the iron in the same dose — so you get more benefit without needing a higher dose.
3. The Dose
Supplement doses between 14–18mg per serving are appropriate for most adults as a daily maintenance dose. Higher doses (65–200mg) are sometimes prescribed for treating established deficiency — but these should be directed by a GP or pharmacist, as excessive iron has risks.
4. Format: Tablets vs Gummies
This is worth addressing directly. Gummies are sometimes dismissed as less "serious" than tablets — but the evidence and clinical experience tell a different story. The most common reason people stop taking iron supplements is gut side effects. If you stop taking it, it doesn't work. Gummies with a well-chosen iron form (bisglycinate) tend to be much better tolerated, leading to better adherence.
5. Verified Vegan Certification
Many iron supplements contain gelatine in their capsules or coating — which obviously isn't vegan. Look for the Vegan Society trademark or a comparable third-party certification.
Frequently Asked Questions
How do I know if I'm iron deficient?
The only way to know for certain is a blood test. Ask your GP for a full blood count and serum ferritin test. Ferritin is the most sensitive early indicator of iron deficiency — you can have low ferritin (and experience all the symptoms) while your haemoglobin is still technically "normal." Don't wait to be told you're anaemic before acting.
Can I get enough iron from a vegan diet alone?
Some vegans do — particularly those who eat a wide variety of iron-rich plant foods and pair them well with vitamin C. But statistically, vegan women are one of the highest-risk groups for iron deficiency. Whether you need to supplement depends on your individual diet, test results, and life circumstances. If in doubt, test.
How long does it take for iron supplements to work?
You may notice improvement in energy levels within 2–4 weeks of starting supplementation. However, rebuilding depleted ferritin stores typically takes 3–6 months of consistent supplementation. If you stop and start, the process takes much longer.
Will iron supplements make me constipated?
Standard ferrous sulphate tablets frequently do — this is one of the most common reasons people abandon iron supplementation. The form of iron matters hugely. Ferrous bisglycinate (used in Vegums Super Iron Gummies) is significantly better tolerated and much less likely to cause constipation or stomach cramps.
Can I take iron with my other supplements?
Iron can interfere with the absorption of some other nutrients — particularly zinc and calcium — if taken at exactly the same time. A 2-hour gap is usually sufficient. Iron is generally absorbed better on an empty stomach, but if it causes nausea, taking it with a small amount of food is fine.
How much iron is in Vegums Super Iron Gummies?
Each serving of Vegums Super Iron Gummies provides 14mg of iron as ferrous bisglycinate, plus added vitamin C. This is 100% of the UK Nutrient Reference Value for iron, in a gentle, well-absorbed form.
Are Vegums supplements certified vegan?
Yes. Vegums is certified by the Vegan Society — the world's oldest and most widely recognised vegan certification body. Every product we make is free from animal-derived ingredients.
The Bottom Line
Iron deficiency is common in vegans — not because plant-based diets are unhealthy, but because plant iron requires more careful management than animal iron. Knowing the symptoms, understanding which foods help and hinder absorption, and supplementing thoughtfully when needed are the practical steps that make the difference.
If you're experiencing fatigue, brain fog, or breathlessness, get tested before assuming you're fine. And if you do need to supplement, choose a form that works gently and effectively — so you actually keep taking it.
Ready to address your iron levels?
Shop Super Iron Gummies →
14mg ferrous bisglycinate + vitamin C | Vegan Society certified | Developed by UK pharmacists | Rated 4.9★ on Trustpilot
Or explore our Wellness Bundle — pharmacist-formulated iron, multivitamin and omega-3 in one subscription package.
References:
- NHS UK. Vitamins and minerals — Iron.
- The Vegan Society. Iron.
- Hallberg L, et al. The role of vitamin C in iron absorption. International Journal for Vitamin and Nutrition Research. 1989.
- Moretti D, et al. Oral iron supplements increase hepcidin and decrease iron absorption from daily or twice-daily doses in iron-depleted young women. Blood. 2015.
- Blanco-Rojo R, et al. Bioavailability of iron supplements: a review. Nutrients. 2017.
