Iron, a vital nutrient

Iron is one of the most common and widespread nutritional deficiencies.  Iron is a vital nutrient and important for transporting oxygen around the body; most people will probably be aware of this function and its link with red blood cells, with the iron containing haemoglobin within the red blood cell carrying oxygen from the lungs to all the organs and tissues in the body. With insufficient iron the body will not function optimally within any of its systems, and can cause fatigue and for you to feel generally below par; you do not have to be anaemic for low iron levels to be affecting you…

Iron plays a role in many other functions within the body:

• Immune function - you may be more prone to infections and viruses if your iron levels are low.

• Iron is the main building block that makes neurotransmitters (such as dopamine, serotonin) - insufficient iron could affect your mood and brain function.

• Thyroid hormones - iron is important for the production of thyroid hormones, iron deficiency can also impair the conversion of thyroid hormones to their active form.

• ATP production (part of energy production) is impaired by low iron levels - this can cause you to feel very tired.

• There is a strong connection between Nitric oxide (NO) and low iron - NO is important for blood pressure regulation and your circulation.

• Iron is also vital for building collagen - which gives your skin, bones and joints their strength.

Involved in so many processes, it is not surprising we can feel a little under par when levels are insufficient, and even worse when deficient.

There are many signs and symptoms of deficiency, not only fatigue and dizziness, but reduction in cognitive performance, sore mouth and tongue, heart irregularities, brittle nails and hair loss, decreased resistance to infection and many more.  When you look at the list of functions above it becomes clearer how insufficient iron can affect almost every cell in the body.

Causes of low Iron levels

Iron deficiency or insufficiency can be for many reasons, in clinic recently I have seen causes which have been linked to other health conditions that affect the gut and have caused decreased iron absorption; other health conditions which led to an increased need for iron, poor absorption due to age and decreased stomach acid, vegan diet, zinc deficiency, athletes with high need due to training. Other causes of low iron levels can be pregnancy, heavy periods, age, IBD (inflammatory bowel disease), CKD (chronic kidney disease), also medication such as PPI (proton pump inhibitors such as Omeprazole).

Blood testing for some clients has identified low iron levels, which has given explanations to them when they weren’t sure if they were tired from “just stress”, or was it peri-menopause symptoms making them feel so fatigued and causing hair loss, or the reason for struggling with getting results from their training despite putting all the effort in.

Test, don’t guess!

My focus in clinic when working with someone to improve their iron levels, is to start with knowing what their blood levels are, which includes not only red blood cell panel to check for anaemia, but also serum iron, ferritin, TIBC (total iron binding capacity), transferrin. If you don’t know all your numbers then it’s just guess work, and can lead to a frustratingly slow improvements in symptoms and how you are feeling. You could be spending money on supplements which may be unnecessary, inefficient or even problematic.  Blood testing can also identify other reasons for symptoms which may not be iron related, which means nutrition and/or supplements can be targeted in the right area to gain improvement in health and symptoms.

When I look at blood test results, whether from the GP or from tests I have done for a client, I will look at whether the levels of any marker, including iron markers, are in the optimal range.  This is where my work differs from the medical view on blood tests, who tend to look at results being within a much wider range and will often comment “satisfactory”.  We can have symptoms or not feel quite right when the results are medically in the ‘normal range’, however I will look to optimise your levels to help you feel like you are thriving rather than just surviving day to day.  So if you have blood tests that are ‘normal’ but you still don’t feel great, then let me look at them and we can review your symptoms to make the links with possible sub-optimal markers.

More than a blood test

Having said that we start with blood, I do not work with your blood test results alone, it is really important for me to understand you as a whole person, your lifestyle, your diet, your eating patterns, your stress levels, your sleep, your digestion, your whole health history.  And then we can work together to understand what has led you to where you are now with your health and feeling the way you do, which will then guide your plan to improve and optimise your health.

What next?

My approach is always food first, so here are a few tips for building a meal focusing on boosting your iron levels:

Haem Iron: Sardines, Salmon, Seafood, Eggs, Meat or Poultry

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Non-Haem Iron: Lentils, Spinach, Red Kidney Beans, Black eye Beans, Pumpkin Seeds

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Vitamin C: Orange, Lemon, Kiwi, Broccoli, Kale

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Vitamin A: Peppers, Kale, Sweet Potato

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Healthy fat: Avocado, Olive oil, Few nuts

Here’s Why

Haem Iron is absorbed easily, and it also enhances the absorption of non-haem iron.

Vitamin C has a significant effect on absorption of iron from non-haem (plant sources) as well as from iron supplements, just adding a small amount Vitamin C containing food to a meal will have a positive effect. Vitamin A foods also enhance the absorption of non-haem iron.

Consuming healthy fat stimulates bile flow which leads to better availability and absorption of non-haem iron.

Maximising absorption: Avoid drinking tea and coffee at the time to eating your iron-rich meal, as the tannins inhibit iron absorption and also keep dairy for another meal.

Supplements:

Testing is important before taking iron supplements, but these can be helpful if iron levels are particularly low and you need support whilst making dietary changes or addressing the root cause of your low iron levels.  Knowing your blood test results will help with working out the correct dosage of your supplement. Ideally blood tests should be repeated 3-4 monthly after making dietary or supplement changes to ensure the blood markers are improving.

Supplementing iron can be problematic if you don’t need to take them, and can cause a number of side effects or damage if excessive iron is accumulated within the body.   Unfortunately it is common for people to try these supplements when they are feeling fatigued, however this is not the only reason for this symptom, so please get tested rather than just guessing.

There are many forms of iron supplements, so please ask advice before buying them. A number of forms of iron can cause side effects including nausea, constipation, diarrhoea; choosing a different form of iron or adjusting timing can really help to reduce these symptoms, so don’t give up if you are struggling with the side effects!

To maximise absorption of iron supplements avoid taking them at the same time as Calcium, Magnesium or Zinc supplements, spread your supplements out during the day.

Get in touch

So please get in contact with me if you would like help and support with low iron levels, or investigating any symptoms that you have or you are interested in blood testing to check your current blood markers related to iron.

Nicky

References

Hurrell, R. and Egli, I. (2010). Iron bioavailability and dietary reference values. The American Journal of Clinical Nutrition, [online] 91(5), pp.1461S-1467S. doi:10.3945/ajcn.2010.28674f.

Kumar, A., Sharma, E., Marley, A., Samaan, M.A. and Brookes, M.J. (2022). Iron deficiency anaemia: Pathophysiology, assessment, practical management. BMJ Open Gastroenterology, 9(1), pp.1–9. doi:10.1136/bmjgast-2021-000759.

Layrisse, M., García-Casal, M.N., Solano, L., Barón, M.A., Arguello, F., Llovera, D., Ramírez, J., Leets, I. and Tropper, E. (2000). New property of vitamin A and beta-carotene on human iron absorption: effect on phytate and polyphenols as inhibitors of iron absorption. Archivos latinoamericanos de nutricion, [online] 50(3), pp.243–8. Available at: https://pubmed.ncbi.nlm.nih.gov/11347293/ [Accessed 29 July 2026].

Lynch, S. and Cook, J. (1980). Interaction of Vitamin C and Iron. [online] Annals of the New York Academy of Sciences. Available at: https://pubmed.ncbi.nlm.nih.gov/6940487/ [Accessed 29 July 2026].