Iron and your thyroid: the overlooked connection that could be affecting your energy
If you’ve been feeling tired, foggy or flat – even though your thyroid test results came back “normal” – there may be another piece of the puzzle worth exploring: your iron levels. Iron and thyroid health are deeply connected and iron deficiency can have a ripple effect across multiple aspects of your wellbeing. Let’s unpack why.
Iron’s critical role in thyroid hormone production
The thyroid gland produces hormones that regulate your body’s metabolism – everything from your body temperature and heart rate to energy levels and how quickly you burn fuel. But in order to make these hormones effectively, your thyroid relies on iron. Iron is a cofactor for an enzyme called thyroid peroxidase (TPO) – a key player in the creation of thyroid hormones. Without adequate iron, this enzyme simply doesn’t function as it should, which means your thyroid can’t produce enough hormones – even if the gland itself is structurally healthy.
Iron helps convert T4 to T3 – your most active thyroid hormone
Your thyroid produces a hormone called T4, which must then be converted into its active form, T3. It’s T3 that really gets things going in your cells. This conversion relies on several nutrients – including selenium, zinc and yes, iron. Low iron can impair this conversion, leaving you with enough T4, but not enough of the hormone that actually does the work. That’s why some people may still experience hypothyroid-like symptoms despite “normal” blood test results.
How low iron impacts thyroid function
Even mild iron deficiency can make a significant difference to how your thyroid performs. Some of the effects include:
- Reduced production of thyroid hormones
- Poor conversion of T4 to T3
- Exacerbated fatigue, brain fog, or weight fluctuations
- Increased hair thinning or loss
- Mood changes or difficulty managing stress
Many of these symptoms overlap with both iron deficiency and low thyroid function – making it tricky to tease apart without proper testing and context.
A two-way relationship
Just as low iron can affect thyroid health, hypothyroidism (underactive thyroid function) can also impair iron absorption. Slower digestive motility, changes in stomach acid and inflammation in the gut – all common in people with thyroid issues – can reduce your body’s ability to extract iron from food.
So you can see: the relationship between iron and thyroid function is circular. If one suffers, the other often does too.
If you suspect low iron might be playing a role in how you feel – especially if you’re already supporting your thyroid but not noticing significant improvements – it’s worth checking your iron status. Look for serum ferritin (your iron stores), and aim for levels above 50 µg/L for optimal thyroid and overall health.
Ready to feel the difference a quality iron supplement can make?
Iconic Iron by Dr Libby is a one-of-a-kind supplement, delivering ferritin iron sourced from organic peas – a unique form of plant-based iron that’s both gentle and highly bioavailable. Unlike standard iron supplements, ferritin iron uses a dedicated absorption pathway that protects the gut lining while ensuring effective uptake into your cells.
This means better absorption, fewer side effects, and real results – especially for those who’ve struggled with traditional forms of iron in the past.
Support your iron and thyroid health with a supplement that’s as smart as your body.
