Iron Deficiency Guide: Symptoms, causes, and what to do
Iron deficiency is the most common nutrient deficiency in the world. It can affect anyone, but it’s especially common in women of childbearing age, pregnant women, women with heavy periods, women who exercise a lot, and vegetarians or vegans. It’s estimated that one out of three women has some level of iron deficiency.
The tricky part? Symptoms are often vague and can easily be mistaken for just being “tired” or “stressed.” This guide walks you through the basics.
Could I have iron deficiency?
Yes, it’s possible. Some people notice clear warning signs, while others don’t feel anything until their levels are very low. Common symptoms include:
Feeling unusually tired or weak
Shortness of breath or fast heartbeat, especially with activity
Dizziness, headaches, or trouble concentrating
Pale skin, brittle nails, or hair shedding
Restless legs
Feeling cold more often than others
Feeling anxious or even depressed
Not everyone has all of these, and symptoms alone don’t confirm iron deficiency. The only way to know for sure is with a blood test.
When you get tested, don’t stop at hemoglobin. Ask for a ferritin test too. Many women are iron deficient even when their hemoglobin levels look normal.
What are normal ferritin levels?
Ferritin is your iron storage marker — think of it as your iron bank account. If ferritin is low, your body is running on empty.
General reference ranges (can vary by lab):
Below 15 µg/L – iron deficiency
15–30 µg/L – very low stores
30–50 µg/L – often reported as “normal,” but many people still feel symptoms
50–100 µg/L – adequate, though some may still notice symptoms
100–300 µg/L – usually healthy stores
Above 300 µg/L – may suggest too much iron or inflammation
A “good” ferritin level depends on your age, sex, health, and whether you have symptoms. For example, athletes, pregnant women, and those planning pregnancy often feel best with higher ferritin levels.
Many labs list anything above 15–30 µg/L as normal, but don’t be misled. Your personal “optimal” ferritin might be much higher. It often takes some testing and reflection to find where you feel your best.
What causes iron deficiency?
There’s no single cause. It usually comes down to losing iron faster than you take it in. Common reasons include:
Blood loss – Heavy or long periods are the number one cause in young women. Many women underestimate their blood loss and don’t realize their periods are considered heavy. Other hidden sources include bleeding from the stomach or intestines (ulcers, polyps, hemorrhoids).
Absorption problems – Conditions like celiac disease, inflammatory bowel disease, or stomach surgery can block absorption. Even mild gut issues without a diagnosis can significantly affect how well your body takes in iron.
Not enough in the diet – Plant-based eaters, people who eat little meat, or those following restricted diets (such as gluten-free) may struggle to get enough.
Iron blockers in food and supplements – It’s not only about how much iron you consume, but also how much you absorb. Grains, certain vegetables, dairy, coffee, and tea all contain compounds that reduce iron absorption. Some supplements also interfere.
Increased need – Pregnancy, breastfeeding, teenage growth spurts, and intense exercise can all raise iron demands.
How do I fix low iron levels?
Fixing iron deficiency usually has two parts: addressing the cause and refilling your iron stores.
Check your periods – If your bleeding is heavy, managing it is a crucial step. Both hormonal and non-hormonal options are available to reduce menstrual blood loss.
Check your gut health – If you have digestive issues, supplements may upset your stomach or not absorb well. In some cases, fixing gut health improves iron levels even without supplements.
Diet changes – Add iron-rich foods like red meat, chicken, fish, lentils, beans, chickpeas, spinach, kale, pumpkin seeds, and fortified cereals. Pair them with vitamin C (fruits, peppers, tomatoes) to boost absorption.
Iron supplements – Most people need supplements to refill stores. Tablets, capsules, or liquid iron are common. Consistency is key, and it usually takes months to see results.
Lifestyle tips – Avoid coffee, tea, or dairy around the same time as iron, since they reduce absorption. Take supplements with a high dose of vitamin C for better uptake. Try different formulations if one causes side effects.
Medical treatments – If supplements don’t work or if your deficiency is severe, your doctor may suggest iron infusions.
How much iron should I take?
There’s no one-size-fits-all answer. Typical supplement doses are 30–100 mg of elemental iron per day, sometimes higher if deficiency is severe. Elemental iron is the “active” part — the amount listed on the label may be higher because it includes other compounds.
Too much iron can be harmful. Always test first and follow your doctor’s advice rather than guessing.
Do I Need an Iron Infusion?
Iron infusions are a fast way to raise iron levels, but they’re not for everyone. They’re usually recommended if:
Oral supplements cause strong side effects
Your body cannot absorb iron properly
Your deficiency is severe and needs urgent treatment (for example, during pregnancy or before surgery)
This is always a doctor’s decision, based on your blood test results. Often you’ll be asked to try supplements first before being referred for an infusion.
Where should I go for treatment?
Your doctor or a health clinic – They can order the right tests and guide you on treatment.
Private labs – In many places, you can book your own ferritin and hemoglobin tests without a referral.
Specialists – If your case is complicated or your symptoms don’t improve, you may be referred to a hematologist or gastroenterologist.
The important thing is to get tested early rather than self-diagnosing. Apps like Ferrivia can help you understand your lab results and support your journey to healthier iron levels, but they are not a substitute for professional medical advice.
If you need personalized support, Ferrivia offers a 3-month Iron Recovery journey membership that helps women understand their iron levels, start feeling better, and take control of their health. Read more at ferrivia.ai/membership
Resources & Further Reading
For more reliable information on iron deficiency, you can check: