What is Ferritin? Find Out What Low and High Results Mean

Got blood test results showing abnormal ferritin levels and wondering what they actually mean? Many Australians discover they have low or high ferritin without understanding what ferritin is or why it matters for their health.

Ferritin is a protein that stores iron in your body. When your doctor orders a ferritin test, they're checking how much iron your body has in reserve, not how much is actively circulating in your blood. Think of ferritin as your body's iron savings account, while serum iron is the cash you have on hand right now.

Key Takeaways:

  • Ferritin is a protein that stores iron in your liver, spleen, and bone marrow.

  • Normal ferritin levels typically range from 30-200 μg/L for women and 30-300 μg/L for men (ranges vary between labs).

  • Low ferritin levels indicate depleted iron stores and often precede iron deficiency anaemia.

  • High ferritin levels can signal inflammation, liver disease, or iron overload conditions.

  • Low ferritin levels (below 15 μg/L) require medical attention and treatment.

Why Ferritin Matters More Than You Think

Your body needs iron for dozens of critical functions, including making red blood cells, supporting immune function, producing energy, and maintaining healthy hair, skin, and nails. Ferritin acts as the storage vault for this essential mineral.

Here's what makes ferritin testing so valuable: it's often the first marker to drop when your iron stores are running low, well before you develop full-blown anaemia. This early warning system gives you and your doctor a chance to address iron deficiency before it impacts your daily life.

Research from the World Health Organisation shows that iron deficiency affects approximately 30% of the global population, making it the most common nutritional deficiency worldwide. 

What Ferritin Levels Tell Your Doctor

When your GP orders a ferritin test, they're looking at your iron storage status. But interpreting ferritin results isn't always straightforward, context matters.

Normal Ferritin Ranges

Standard reference ranges are:

  • Women: 30-200 micrograms per litre (μg/L)

  • Men: 30-300 μg/L

  • Children: Varies by age, typically 7-140 μg/L

These ranges represent what's "normal" in the population, but optimal levels for energy, cognitive function, and overall well-being often sit higher – between 70-125 μg/L for most people.

When Ferritin Results Need Context

Ferritin isn't just an iron marker. It's also an acute-phase reactant, meaning that inflammation, infection, or chronic disease can artificially elevate your levels. If you've got a cold, active autoimmune condition, or chronic inflammation, your ferritin might look normal or even high even if your actual iron stores are depleted.

This is why experienced functional medicine practitioners look at ferritin alongside other markers, such as serum iron, transferrin saturation, and total iron-binding capacity, to get the complete picture.

What are Dangerously Low Ferritin Levels?

Dangerously low ferritin levels typically fall below 15 μg/L, though some functional medicine practitioners consider anything under 30 μg/L concerning, depending on your symptoms.

At these levels, you've exhausted your iron reserves. Your body starts prioritising where to send the limited iron available, often sacrificing hair growth, energy production, and immune function to keep vital organs functioning.

Symptoms of Low Ferritin Level

You might notice:

  • Fatigue

  • Shortness of breath with minimal exertion

  • Pale skin and brittle nails

  • Frequent infections as your immune system struggles

  • Hair loss or thinning

  • Difficulty concentrating or "brain fog"

  • Restless legs syndrome, especially at night

These signs of low iron can develop gradually, so you might adapt to feeling subpar without realising something's wrong.

What Causes Low Ferritin?

Common reasons for depleted iron stores include:

  • Heavy menstrual bleeding 

  • Pregnancy and breastfeeding

  • Poor dietary intake of iron-rich foods, particularly in vegetarian or vegan diets

  • Malabsorption issues like coeliac disease, inflammatory bowel disease, or low stomach acid

  • Blood loss from ulcers, polyps, or regular blood donation

  • Intense athletic training

Understanding High Ferritin Levels

A high ferritin level (generally above 200 μg/L in women or 300 μg/L in men) doesn't always mean iron overload. Remember, ferritin rises with inflammation.

When High Ferritin Signals a Problem

Genuinely elevated ferritin from iron overload occurs in conditions like:

  • Haemochromatosis: A genetic condition causing excessive iron absorption

  • Frequent blood transfusions over time

  • Chronic liver disease, which disrupts iron regulation

  • Excessive iron supplementation without proper monitoring

When High Ferritin Reflects Inflammation

More commonly, elevated ferritin indicates:

  • Chronic inflammatory conditions (eg rheumatoid arthritis)

  • Metabolic syndrome or insulin resistance

  • Non-alcoholic fatty liver disease

  • Active infections

  • Some cancers

Your doctor will run additional tests to determine whether you have true iron overload or if inflammation is driving the elevated reading.

How to Correct Ferritin Imbalances

Addressing Low Ferritin

Treatment depends on severity and underlying cause:

  • Dietary changes: Increase iron-rich foods like red meat, liver, shellfish, legumes, and dark leafy greens. 

  • Oral iron supplements: Often the first-line treatment, though they can cause digestive upset and take 3-6 months to restore stores.

  • Iron infusions: For severe deficiency, poor tolerance of oral supplements, or malabsorption issues, iron infusions provide rapid restoration of iron stores. Many patients notice improvement within days to weeks, though full restoration of stores typically takes several weeks.

  • Address underlying causes: If heavy periods are the culprit, you'll need to manage that. If it's malabsorption, treating the gut issue is essential.

Managing High Ferritin

For inflammation-driven high ferritin, focus on the root cause:

  • An anti-inflammatory diet rich in omega-3 fatty acids

  • Managing chronic conditions effectively

  • Reducing metabolic stress through lifestyle changes

For genuine iron overload:

  • Therapeutic phlebotomy (regular blood removal)

  • Avoid iron supplements and limit iron-fortified foods

  • Genetic testing if haemochromatosis is suspected

When to Test Your Ferritin

You should seek medical attention and get a thorough work up, including ferritin testing if you're experiencing:

  • Persistent fatigue despite adequate sleep

  • Any symptoms of iron deficiency

  • Diagnosed anaemia (to determine if iron deficiency is the cause)

  • Planning pregnancy or currently pregnant

  • Following a vegetarian or vegan diet

  • Diagnosed inflammatory or autoimmune conditions

  • Family history of haemochromatosis

At Evergreen Doctors, we don't just test ferritin in isolation. We assess your complete iron panel, inflammatory markers, and other nutritional status indicators to understand what's really happening in your body. This comprehensive approach means we're treating the root cause, not just chasing numbers on a lab report.

Getting the Right Support for Ferritin Issues

If you're dealing with abnormal ferritin levels, working with practitioners who understand functional medicine makes a significant difference. Cookie-cutter approaches to iron supplementation often fail because they don't address why your ferritin is abnormal in the first place.

Our functional medicine team seeks the root causes of nutritional imbalances and chronic health issues. We combine comprehensive testing with personalised treatment plans that address your unique biochemistry, not just your symptoms.

Whether you're struggling with unexplained fatigue, have received concerning blood test results, or want to optimise your health proactively, we'll help you understand what ferritin is and what your specific levels mean for your wellbeing.

Chris Chappel