The importance of iron
If you have been feeling a little irritable, tired or headachy lately, it could be that something is amiss with your iron status.
Iron is responsible for carrying oxygen around the bloodstream and for red blood cell production — essential for our energy power house, mitochondria. Without the necessary dietary iron, we are unable to carry oxygen from the lungs to other parts of the body and iron stores can become depleted, leading to the fatigue or tiredness we often put down to the busy-ness of everyday life.
Outside of the role iron plays in energy production, it is intricately tied to the many pathways related to enzymes, hormones and musculoskeletal tissue:
- The formation of collagen (the main component of our connective tissue in the body) relies on iron and without it our ability to repair and to generate tissue is compromised.
- Iron also forms part of important neurotransmitters — for example, serotonin, the “feel good” neurotransmitter, requires iron; low levels of serotonin have been found in people with inadequate iron status.
- Iron supports cognitive functioning and development, therefore it is essential for adequate brain function for young and old alike.
- Iron plays an important role in our digestive tract, without which the ability to absorb and transport other nutrients is diminished. This relationship is obviously not one-way; for people who already suffer from gastrointestinal issues, or have a low stomach acid production, the ability to absorb iron (along with other important vitamins and minerals) may be compromised despite an adequate dietary intake.
The fatigue people can feel from the early stages of iron deficiency is not just related to lack of oxygen in red blood cells. A low iron status can slow the conversion of T4 to T3 — the “inactive” to “active” thyroid hormone, necessary for healthy thyroid metabolism. Though cortisol, our “stress” hormone, is often talked about in the context of low energy and adrenal dysfunction, and the focus is on efforts to lower it, the latter stages of chronic fatigue and dysfunction occur when the adrenal glands are unable to produce enough cortisol, a pathway that relies on many nutrients, including iron.
The first thing to do if you suspect you are low in iron is to get a blood test. Fatigue, irritability, headaches and hypotension can be the result of many modern health conditions and not just low iron status. As too much iron through unnecessary supplementation can result in toxicity in the body, it is important to have an iron deficiency diagnosed before beginning to take supplements. Outside of supplementation, increasing your intake of iron-rich foods can certainly increase your iron status.
Eat your iron
Hands down, our best dietary source of iron comes from organ meat. This is likely the least popular suggestion for increasing dietary iron intake, but I challenge you to at least try it! While the term “superfood” is - in my opinion - overused, if ever there was a food I would concede on, it would be liver.
Of course, red meat is another brilliant source of iron. One of the reasons women are more at risk of becoming iron deficient (one in 14 women in the NZ population) is not only due to increased losses through the menstrual cycle, but an avoidance of red meat in the mistaken belief that it is high in fat and therefore contributes to weight gain.
Can I please set the record straight right now: red meat is one of THE most nutrient-dense food sources in our modern diet and is about as far removed from our modern day health crises as any food could be. High in protein (more satisfying), rich in B vitamins (important in energy metabolism), an important source of good dietary fat (including omega 3s, given our red meat sources are grass-fed), for people who include meat in their diet, you can’t go wrong with this choice. While red meat has been implicated in cancer, cardiovascular disease and other inflammatory conditions, this is drawn from observational studies where it is impossible to detect cause and effect.
Further, fresh red meat is grouped with processed red meat such as sausages, burger patties, salami and luncheon — it’s well established that these meats contribute to inflammatory pathways in the body that DO increase our risk of chronic disease.
Finally, those processed meats are often consumed alongside white bread, high sugar sauces and soft drinks (think: the traditional combo meal) which will confound the results in such a way that is difficult to account for despite statistical methods used.
Outside of red meat, mussels, oysters and organ meats are even richer sources of dietary iron but are often overlooked as they do require a more refined palate.
Eggs are also rich in iron, and plant-based sources of iron include green leafy vegetables, nuts such as cashews and almonds, dried fruit such as raisins and apricots and cruciferous vegetables.
Those people who choose a vegetarian diet need to be more considered with their food choices for sure, as many of our plant-based sources of iron are also high in phytates and oxalates which are compounds that bind dietary iron and prevent the absorption of it.
The inclusion of vitamin C-rich fruit and vegetables and vitamin A-rich foods (such as butter, which won’t inhibit absorption as it’s negligible in milk protein and calcium) will aid the absorption, whereas milk (calcium), tea (tannins) and coffee (polyphenols) are best consumed outside meal times. Though cereals, juices and breads are often fortified with iron, your best sources really are foods that naturally contain dietary iron as the synergy of nutrients in these foods will enhance the absorption and utilisation of all minerals, including iron.
Mikki Williden is a registered nutritionist and lecturer at AUT University, where she lectures in public health nutrition and sports nutrition at the School of Sport and Recreation. Read Bite articles from Mikki or visit mikkiwilliden.com for more.
We've selected a few of our favourite iron-rich recipes here, for more check out the Iron-rich recipe collection.