Understanding Iron Deficiency

With 25% of the world’s population deficient in iron, it’s the most common nutrient deficiency, globally. Despite common belief however, the risk of deficiency does apply to meat eaters.  

Iron is an essential nutrient for most living organisms. Among other roles, it’s used to produce haemoglobin which is what enables red blood cells to transport oxygen throughout the body. It is therefore crucial for energy production and in turn, athletic performance. 

What happens when iron levels are low? 

Low iron comes in varying degrees, from initially having low iron stores (as indicated by low serum ferritin and transferrin); to early iron deficiency (indicated by decreased serum transferrin saturation) to iron-deficiency anaemia (indicated by low haemoglobin and haematocrit as well as reduced mean corpuscular volume (MCV)). 

It’s therefore important when assessing iron levels, to avoid simply viewing serum iron. For a complete view of oxygen carrying capacity, review and request the following from your GP: 

  • Transferrin
  • Transferrin Saturation 
  • Ferritin
  • Full Blood Count 
  • C-reactive protein (CRP)

True low iron may manifest with many symptoms including dizziness, headache, shortness of breath, fatigue, brittle nails, heart palpitations and restless legs. 

Who’s most at risk of low iron? 

  • Menstruating females, particularly those with heavy periods. 
  • Those suffering from blood loss, possibly caused by peptic ulcers, colorectal cancer or hiatus hernia.
  • Those with Irritable Bowel Disease (IBD), Coeliac Disease, Small Intestinal Bacterial Overgrowth (SIBO) or other conditions causing disturbance to nutrient absorption. 
  • Vegans and vegetarians or those with poor dietary intake of iron. 
  • Those with an eating disorder. 
  • Those on stomach acid supressing medication or with low stomach acid levels. 
  • Frequent blood donors. 

How can you prevent low iron levels? 

1. Consume adequate amounts of dietary iron: 

For most people, consuming the Recommended Dietary Intake (RDI) should be enough to prevent Iron Deficiency or Iron Deficiency Anaemia. In Australia, RDIs are as follows: 

  • Males and females over 51 years of age: 8mg/day. 
  • Females of menstruating age: 18mg/day.
  • Please note: vegans and vegetarians: requirements are 1.8% greater due to a lack of haem iron within the diet. 

Dietary iron comes in two forms, haem (from meat, fish and poultry) and non-haem (from nuts, seeds, legumes and green leafy vegetables). Non-haem iron is less readily absorbed which is why requirements are greater when it offers the only dietary source of iron. For most, consuming a portion of protein with each meal from a wide variety of iron containing foods (those listed above) is enough to maintain adequate iron levels.  

2. Support absorption of iron:

For vegans and vegetarians relying mainly on plant based sources, supporting the absorption of non-haem iron will help to maximise the iron present in the plant-based diet. Do this by:

  • Consuming non-haem iron containing foods alongside vitamin C. Foods high in vitamin C such as berries, spinach, broccoli, capsicum and tomato will support non-haem iron absorption. 
  • Vitamin A and β-carotene enhance non-haem iron absorption so consider consuming dietary sources alongside non-haem iron containing foods. Look to carrots, sweet potato, spinach, kale and capsicum. 
  • Phytates found in legumes, nuts and seeds can negatively impact non-haem iron absorption. Soaking or sprouting these foods prior to consuming can reduce the phytate content thereby supporting better iron absorption. Optimal gut health is also important as the right bacteria could play a role in breaking down phytates. 

Even if you do consume haem iron, please avoid consuming tannins (found in tea, green tea and coffee) as these can impair absorption. 

If using an iron supplement, avoid having these at mealtimes or when having zinc or calcium containing supplements as these will also impair absorption. In particularly persistent cases of iron deficiency and/or anaemia, combining supplemental iron with an active B12, vitamin A or lactoferrin may make all the difference. Of course, what’s most appropriate will be relevant to the individual and their stage in life which is why it’s important to seek tailored advice.  It’s a misconception that treating iron deficiency is as simple as ‘a pill for an ill’.  

3. Optimise gut health: 

Remember, we are what we digest and absorb. Support the initial stages of digestion and ultimately absorption with adequate stomach acid. If you have a history of (or a suspicions of) hypochloridria (low stomach acid), bitters (such as lemon juice, apple cider vinegar, dandelion and gentian) can be a good starting point for regaining adequate digestive secretions and always avoid eating when stressed as the sympathetic nervous system will detract from digestive secretions.

It’s also important to consider and maintain the integrity of the intestinal lining as the junctions within it are responsible for regulating nutrient absorption. The presence of oxidative stress and inflammation has been shown to promote ‘loosening’ of the junctions which is otherwise commonly referred to as ‘leaky gut’. Reduce risk of inflammation in the gut by nurturing a thriving gut microbiome

4. Normalise menstrual blood loss:

And last but certainly not least, it is essential to determine your monthly menstrual blood loss, where 40-80ml is ideal. In excess of 80ml is the root cause for almost all of my female clients with true low iron, and something I specialise in treating via my 1:1 consultations.

Ultimately, for most, consuming more than adequate amounts of iron isn’t a challenge. Yet with such high rates of inadequacy it suggests the attention needs to be elsewhere – attention needs to be placed treating the true root cause of the low iron. 

What about iron supplements?

As a general rule I don’t recommended synthetic iron supplements, however in certain situations, there may be reason to supplement with iron. I always recommend working with a practitioner to determine the right supplement and dosing regime to suit your specific needs. 

Please leave your comments below or get in touch should you wish to get started with a complimentary 15 minute consultation

For a self-paced guide, access my Understanding Low Iron masterclass today. 


Young I et al., 2018. Association Between Haem and Non-Haem Iron Intake and Serum Ferritin in Healthy Young Women. Nutrients, 10, 1, 81. 

Nutrient Reference Values for Australia and New Zealand. (accessed June 2020).

FoodData Central Search Results. (accessed June 2020). 

Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. (accessed June 2020). 

Saunders A, 2013. Iron and Vegetarian Diets. The Medical Journal of Australia, 199, 4, S11 – S16. (accessed June 2020).

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