Iron Deficiency: What Many Women Don't Know

Feeling tired, exhausted, constantly cold, or simply not quite like yourself? Many women assume these symptoms are caused by stress, lack of sleep, or hormonal changes throughout the menstrual cycle. However, iron deficiency may also be the underlying cause.

What's particularly interesting is that iron deficiency and menstruation influence each other. While your period can gradually deplete your body's iron stores, low iron levels can also leave you feeling even more fatigued during certain phases of your cycle.

In this article, you'll learn what many people don't know about iron deficiency, which symptoms to look out for, and why women are particularly affected.

Why Iron Is So Important for Your Body

Iron is one of the body's most important minerals. It is essential for the production of haemoglobin, the protein in red blood cells that transports oxygen throughout your body. Iron also plays an important role in:

• Energy production
• Concentration and cognitive function
• Physical performance
• Immune function
• Cell regeneration

When your iron stores become depleted, less oxygen reaches your cells. As a result, you may feel tired and exhausted more quickly, even if you've had enough sleep.

Women Are Particularly at Risk

What many people don't realise is that iron deficiency is one of the most common nutrient deficiencies worldwide. Menstruating women and adolescent girls are particularly affected. According to the World Health Organization (WHO), women of reproductive age are among the groups at greatest risk of iron deficiency and anaemia.

The reason is simple: with every menstrual period, your body loses blood, and with it, iron. Women with heavy menstrual bleeding can lose significantly more iron each month.

Additional factors that may increase the risk include:

• Heavy or prolonged menstrual periods
• Pregnancy and breastfeeding
• Vegetarian or vegan diets without sufficient iron intake
• Intense physical activity
• Certain gastrointestinal conditions that reduce iron absorption

Iron Deficiency Often Begins Long Before Anaemia

Many people associate iron deficiency directly with iron deficiency anaemia. In reality, your body's iron stores can become significantly depleted long before anaemia appears in a blood test.

This means you may already experience typical symptoms even though your haemoglobin levels are still within the normal range. If iron deficiency is suspected, it is often helpful to have not only your haemoglobin but also your ferritin levels (iron stores) checked.

These Symptoms Are Often Overlooked

Iron deficiency does not always present with obvious symptoms. Many signs develop gradually and are often attributed to other causes.

Common symptoms include:

• Fatigue and exhaustion
• Difficulty concentrating
• Dizziness
• Headaches
• Shortness of breath during physical activity
• Cold hands and feet
• Increased susceptibility to infections
• Hair loss
• Brittle nails
• Reduced physical performance

Many women also report never feeling truly rested, even after getting enough sleep.

How Iron Deficiency and Your Menstrual Cycle Are Connected

The relationship between iron and the menstrual cycle goes far beyond monthly blood loss.

Heavy Periods Can Deplete Iron Stores

Women who experience consistently heavy or prolonged periods may lose more iron each month than their bodies can replace. Over time, iron stores gradually decline, often without noticeable symptoms at first.

Iron Deficiency Can Make PMS Symptoms Worse

Although iron deficiency does not directly cause premenstrual syndrome (PMS), it can intensify symptoms such as fatigue, low energy, difficulty concentrating, and exhaustion. Many women notice these symptoms most strongly during the late luteal phase, just before their period begins.

Your Period Is Not Always the Only Cause

It's also important to remember that not every woman with iron deficiency experiences heavy menstrual bleeding.

Low dietary iron intake, reduced iron absorption in the gut, or increased iron requirements can also contribute. That's why persistent symptoms should always be assessed individually by a healthcare professional.

Iron-Rich Foods for Everyday Life

A balanced diet can help support healthy iron levels.

Foods that are naturally rich in iron include:

• Red meat
• Liver
• Legumes
• Lentils
• Chickpeas
• Tofu
• Pumpkin seeds
• Sesame seeds
• Oats
• Millet

Good to know: Vitamin C can improve iron absorption. Pairing iron-rich meals with vitamin C-rich foods, such as oranges, peppers, berries, or citrus fruits, can help your body absorb more iron.

On the other hand, drinking coffee or black tea with meals may reduce iron absorption.

Why Iron Doesn't Work Alone

Maintaining healthy iron levels isn't only about how much iron you consume. It's also about how effectively your body can absorb and utilise it. This is where important cofactors come into play.

Vitamin C helps increase iron absorption in the small intestine and is especially effective at improving the absorption of plant-based (non-haem) iron. That's why it's beneficial to combine iron-rich meals with vitamin C-rich foods such as bell peppers, broccoli, berries, or citrus fruits.

Copper also plays an important role in normal iron metabolism. This trace mineral helps transport absorbed iron to where it is needed, including the production of healthy red blood cells. If copper levels are too low, iron utilisation may be impaired, even if enough iron is being consumed.

For this reason, high-quality iron supplements often contain not only iron itself, but also carefully selected cofactors such as vitamin C and copper to support healthy iron metabolism.

When You Should Have Your Iron Levels Checked

If you regularly experience severe fatigue, exhaustion, dizziness, or very heavy menstrual bleeding, it may be worth asking your healthcare provider to check your iron levels.

This is especially important if you:

• Have heavy menstrual bleeding
• Are trying to conceive
• Are pregnant
• Experience frequent hair loss
• Feel persistently tired without a clear explanation
• Follow a vegetarian or vegan diet and suspect you may not be getting enough iron

Conclusion: Iron Deficiency Is More Than Just Feeling Tired

Iron deficiency often develops gradually, making it easy to overlook. Because women lose iron through menstruation every month, they are among the groups most at risk.

If you constantly feel exhausted, struggle with concentration, or experience heavy menstrual bleeding, it's worth paying attention to your iron stores. Adequate iron supports not only healthy oxygen transport throughout the body, but also energy levels, physical performance, and overall wellbeing throughout your menstrual cycle.

References

• World Health Organization
• C. Breymann: Treatment of Iron Deficiency in Women (2013)
• WHO Fact Sheet: Anaemia (2025)
• Cappellini et al.: Iron Metabolism and Iron Deficiency Anemia in Women (Fertility and Sterility, 2022)

FAQ About Iron Deficiency

How can I tell if I have an iron deficiency?

Common signs of iron deficiency include fatigue, exhaustion, difficulty concentrating, dizziness, headaches, hair loss, and cold hands and feet. Because these symptoms often develop gradually, iron deficiency frequently goes unnoticed for a long time.

Why are women more likely to develop iron deficiency than men?

Women lose blood, and therefore iron, during menstruation. Heavy or prolonged periods can gradually deplete the body's iron stores. Iron requirements also increase during pregnancy and while breastfeeding.

Can my period cause iron deficiency?

Yes. Heavy menstrual bleeding is one of the most common causes of iron deficiency in women. If your body loses more iron each month than you take in through your diet, an iron deficiency can develop over time.

Which blood tests can detect iron deficiency?

Iron deficiency is commonly assessed by measuring ferritin (your body's iron stores), haemoglobin, and other iron-related markers. A normal haemoglobin level does not always rule out iron deficiency, as iron stores often become depleted before anaemia develops.

Which foods are highest in iron?

Iron-rich foods include lentils, chickpeas, tofu, pumpkin seeds, oats, millet, and meat. Combining these foods with vitamin C-rich ingredients can help improve iron absorption.

Can iron deficiency cause hair loss?

Yes. Iron deficiency can contribute to diffuse hair loss. However, hair loss can have many different causes, so it's important to speak with a healthcare professional to determine the underlying reason.

Can iron deficiency affect my menstrual cycle?

Iron deficiency does not directly affect your menstrual cycle, but it can make symptoms such as fatigue, low energy, and difficulty concentrating more noticeable. Many women experience these symptoms more intensely around the time of their period.

How long does it take to restore iron levels?

This depends on the severity of the deficiency. Rebuilding your body's iron stores often takes several weeks or even months. Regular follow-up testing can help monitor your progress.

Can I have iron deficiency without anaemia?

Yes. Your iron stores can become depleted long before iron deficiency anaemia develops. This is why some women experience fatigue and exhaustion even though their haemoglobin levels are still within the normal range.