Low Iron Thyroid Function

Low Iron can affect thyroid function 

Studies have shown a link between low iron levels and thyroid function. Iron deficiency has been shown to reduce thyroid hormone production and low levels of TPO. Studies show iron can lead to decreased levels of both T4 and T3 hormones and is also a predicter of poor thyroid status in pregnancy. 

Iron, along with Iodine, Selenium and Zinc are used to make our thyroid hormones. Low iron can decrease deiodinase activity, slowing down the conversion of T4 to T3 and increasing levels of Reverse T3 which is an inactive form.

If you notice symptoms of low iron such as tiredness, hair loss, pale skin, feeling weak or have a history of low iron then it would be worthwhile getting your levels checked with your GP.

Women, smokers, vegans, vegetarians and children are more at risk of being anaemic or low in iron. Women who have heavy menstrual cycles are also at a high risk of being low in iron.

Some tips in how iron levels can be increased:

  • Increasing foods in your diet that are high in iron regularly throughout the week. Iron levels should be increased through heme-iron sources which are better absorbed than non-heme.
  • Heme iron foods include; fish, chicken, turkey, shellfish and red meat. Red meat and sardines are particularly high.
  • Including foods rich in vitamin C alongside an iron rich food can increase your absorption of iron in the meal. Studies show that vitamin C can increase iron absorption double to triple fold. Some of my favourites rich in vitamin C are; Kale, Spinach, kiwis, apricots, berries, yellow peppers, radish, sweet potatoes and broccoli.
  • When cooking vegetables rich in vitamin C be mindful of the loss of vitamin C in the cooking water, as vitamin C is a water-soluble vitamin. Add vegetables to curries, stir-fries and stews to retain the vitamin C in their sauces.
  • Avoid or reduce foods rich in phytates or tannins which block your absorption of iron; phytates and tannins can be found in tea, grapes, wine and grains. You do not need to avoid these foods, but you should consider reducing them if consumption is high.
  • Increase heme-iron foods and avoid relying solely on non-heme foods which are not digested as well. Non-heme iron foods include eggs, tofu, green leafy veg, pulses and fortified foods. If you are a vegan and levels are low consult with a Nutritional Therapist on an easily absorbable and good quality iron supplement.
  • Improving your digestion can improve iron absorption; if you are a smoker or person who eats on the run a lot you could increase your iron levels by making some changes to your digestion.

Improving your digestion for improved iron levels:

When your gut is inflamed due to IBS or IBD, food intolerances or impaired digestion the level of inflammation can increase hepcidin in the liver which is responsible for inhibiting ferroportin, a protein responsible for transporting iron into circulation. Inflammation chemicals can also decease the lifespan of red blood cells that carry our iron for us. 

You can improve your digestion and decrease gut inflammation by:

  • Eating mindfully and inviting your body to prepare for the meal it is about to receive by cooking it, smelling it, anticipating it and making it appetising with flavours and spices. Digestive juices will flow and increase your body’s natural digestion processes through sensory feedback.
  • Avoiding foods that are highly processed and irritable to the gut lining
  • Reducing stress levels which decrease digestion, add in some relaxing or destressing activity into your life on a regular basis to counter-act stress
  • Eat more fresh foods such as salads and raw vegetables along side main cooked meals to stimulate digestive juices to flow.
  • Reduce smoking or get some support to quit as smoking inhibits digestion and decreases absorption of iron and other vitamins and minerals

If you are unsure how to go about preparing iron rich meals or have some digestive symptoms contact one of our Nutritional Therapists who can guide and support, you in making sustainable changes.


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