The underappreciated link between iron and mood, anxiety and depression

When most people think of iron, they think of energy. And while iron’s role in oxygen transport and physical vitality is well known, its influence on our emotional wellbeing is often overlooked.

But research – and real-world results – continue to reveal that low iron isn’t just about feeling tired. It may be one of the hidden drivers behind mood challenges, increased anxiety, irritability, poor focus, and even depressive symptoms.

Some of the symptoms of any degree of iron deficiency can involve our mood. Anxiety, a flatness, low and depressed mood, as well as issues with sleep and irritability, can all show up when you are iron deficient.

Let’s unpack the science.

How iron shapes your brain chemistry

Iron is essential for producing several neurotransmitters – the brain’s chemical messengers that contribute to how we feel, think and respond to life. Three key ones rely heavily on iron:

Dopamine

Dopamine fuels motivation, energy and drive. It’s made from an amino acid called tyrosine, which we get from protein-rich foods – but to convert tyrosine (or its precursor, phenylalanine) into dopamine, your body needs iron. Low iron slows this process, which can show up as low motivation, lack of focus, flat mood and reduced energy.

Serotonin

Often called our “feel-good” neurotransmitter, serotonin supports emotional balance, resilience and healthy sleep. We make it from the amino acid tryptophan, but iron is one of the key nutrients needed for the conversion. Without enough iron, serotonin production can falter – leaving you more vulnerable to irritability, overwhelm, low mood and disrupted sleep.

GABA

GABA acts as a natural calming agent, helping to quiet excess nervous system activity. Iron is required to convert glutamate into GABA. When this process is compromised, you may feel more anxious, restless or struggle to unwind enough for restorative sleep.

When iron levels are low, the production of all three neurotransmitters can suffer – which may explain why low iron so often comes with mood and cognitive symptoms, even when fatigue isn’t the main complaint.

What the research says 

A 2023 study explored the link between iron deficiency anaemia and mental health. It found that people low in iron often experienced fatigue, low mood, anxiety, restlessness, heart palpitations and headaches – symptoms that were sometimes mistaken for depression or other conditions we currently think of as primarily psychological or psychiatric.

The encouraging news? When iron deficiency was corrected, symptoms like anxiety, low mood, lack of motivation and poor sleep improved. For some, they were resolved. The researchers concluded that iron status should be carefully assessed before assuming mood symptoms have another cause.

Why copper matters too

Iron doesn’t work alone. It relies on copper to be transported and stored effectively in the body. A copper-dependent protein called caeruloplasmin is needed for both iron storage and mobilisation, ensuring the iron you obtain through food and supplements can be delivered to the sites that require it.

When copper is low, iron can accumulate in organs like the liver and spleen, yet the brain – particularly the hippocampus, which is central to mood and memory – can become iron deficient. Research shows this imbalance can trigger:

• Increased anxiety

• Higher stress hormone levels

• Changes in brain chemistry that make emotional balance harder to achieve

This is why nutrient synergy matters – healthy iron metabolism depends on a range of nutrients, not just iron itself.

What can you do?  

If your mood has been off and you can’t pinpoint why, it’s worth checking your iron status. Ask your healthcare provider for a full iron panel (called “iron studies”), including ferritin (iron storage). For optimal function – especially if you have symptoms – Dr Libby recommends targeting a ferritin level of at least 50–100 μg/L. Transferrin, an iron “taxi” and measured as part of the iron studies panel, will elevate when your body is hungry for iron. The normal range is 2–3.6 g/L. Once it’s above 2.6 g/L, it’s a sign your body is seeking more iron.

If you need to supplement, choose a form that’s well absorbed and gentle on the gut, like ferritin-iron. Many conventional, old-school iron salts can cause constipation, nausea or stomach pain. At Bio Blends, our Iconic Iron formula contains ferritin-iron from organic peas, along with nutrients co-factors, like copper. After eight years of research and development, its ground-breaking and unique absorption mechanism means it is highly bioavailable, without the common side gut-related effects.

Correcting low iron isn’t just about restoring energy. It’s about supporting your mood, focus, resilience, hormones (thyroid and ovarian), and overall sense of wellbeing – so you can feel more like yourself again and truly, deeply enjoy your life.