Everything You Need to Know About Iron Deficiency
Iron deficiency is the most common nutrient deficiency worldwide. We need iron for haemoglobin production, energy production, growth & development, immunity, mental function & even proper digestion. So when we don’t have enough of it, we tend to feel awful.
Symptoms of iron deficiency include:
Fatigue - This can range from just a bit tired, to extreme exhaustion where you may struggle to get out of bed in the morning or struggle to get through the day without a lie-down.
Poor cognition - This can look like poor memory, inability to focus or think properly, foggy brain, going blank, or taking longer to process information.
Dizziness/lightheadedness - This is caused by a lack of oxygen to the brain. May be more noticeable when getting up from a seated or lying position.
Paleness - General paleness is a classic sign of iron deficiency. The best way to tell is by pulling down your lower eyelid or poking out your tongue in the mirror. If they are more of a pale pink rather than red, then this can indicate low iron.
Shortness of breath - This is usually a sign of more advanced iron deficiency and is especially noticeable during exercise.
Poor immunity - This can look like frequent colds (more than 3 a year) and taking a long time to recover (more than 10 days). It can also look like recurrent infections and slow wound healing.
Heart palpitations - Feeling like your heart is going to beat out of your chest. Often more noticeable at night when going to sleep.
Dry hair & skin - This is caused by a lack of oxygen supply to the hair and skin which leads to dryness & weakness. It can also lead to hair thinning or hair loss.
Cold hands & feet - Feeling cold in general, or cold hands and feet can be caused by a lack of oxygen supply.
Sore/swollen mouth or tongue - Can indicate iron deficiency.
Restless legs - If you’ve ever gotten into bed at night and suddenly noticed a strong uncomfortable urge to move your legs or cross your toes, this is called restless leg syndrome. Iron deficiency is one of the many causes of this condition.
Depression - Those with iron deficiency may be more at risk of depression.
Strange food cravings - A craving for non-food items is called pica. It usually involves things like ice, dirt, paper, sand, or chalk. This can be caused by iron deficiency.
It’s important to note that these symptoms can also be signs of other nutrient deficiencies or health conditions. And not everyone with iron deficiency will display all of these symptoms.
What causes iron deficiency?
Iron deficiency is commonly attributed to a lack of iron in the diet. However, there are many different causes of iron deficiency including:
Blood Loss - The most common and unavoidable form of blood loss is menstruation, which is of particular concern when there is heavy bleeding. Bleeding can also occur due to physical trauma, surgery, intestinal parasites or gastrointestinal conditions that cause internal bleeding.
Increased demands - During pregnancy the demand for iron increases significantly, which can lead to depletion of iron stores.
Decreased absorption - Iron absorption is reliant on stomach acid and certain enzymes within the gastrointestinal tract. Low stomach acid, known as hypochlorhydria is caused by high-stress levels, H.pylori infection, high alcohol intake, and deficiencies in zinc, B vitamins and even iron (it can be a self-perpetuating cycle). Damage to the intestinal mucosa also contributes to decreased iron absorption, and one of the main causes of this is undiagnosed celiac disease.
Another factor that decreases iron absorption is phytochemicals in foods such as phytic acid & tannins which bind to iron molecules and prevent their absorption in the body. These are found in whole grains, legumes, nuts, seeds, coffee & tea.
Chronic infection - Pathogens and viruses require iron to grow and thrive. The body knows this, and so one of the body’s non-specific immune mechanisms is to inhibit intestinal iron absorption and lower serum iron levels by storing iron away. If an infection is chronic and ongoing then this can become problematic as iron stores become depleted.
The three stages of iron deficiency:
Iron depletion - This is where haemoglobin levels are normal but ferritin (or iron stores) are low. Not everyone will experience symptoms in this stage.
Iron deficiency - This is where ferritin stores and serum iron levels are decreased, transferrin levels are increased (transferrin is like a bus that transports iron around your body, so think of it as more seats available on the bus) and transferrin saturation is decreased (lots of empty seats on the bus). Haemoglobin is also decreased.
Iron deficiency anaemia - Once iron deficiency has progressed to this stage, anaemia has set in. This is where red blood cells are smaller in size and haemoglobin is decreased. Lots of symptoms are usually experienced in this stage.
How much iron do we need?
For those who are vegan, vegetarian or simply don’t eat many animal products, the Recommended Dietary Intake (RDI) for iron is 1.8x higher because iron is not as easily absorbed from plants.
Women aged 19-50: 18mg/day / Vegan: 32mg/day
Pregnancy: 27mg/day / Vegan: 49mg/day
Women aged 50+: 8mg/day / Vegan: 14mg/day
Men aged 19-70+: 8mg/day / Vegan: 14mg/day
Plant-based sources include:
Spinach, tofu, chia seeds, lentils, beet greens, silverbeet, tempeh, cashews, black beans, chickpeas, peas, bok choy, edamame, quinoa, oats, sweet potato, kidney beans, tahini, pumpkin seeds, sunflower seeds, dried apricots, dried figs, pistachios, almonds, parsley, mint.
Most of these foods contain between 1-4mg of iron per serve.
How to improve iron absorption:
Vitamin C helps improve iron absorption so pair the foods above with foods high in vitamin C: lemon, kiwi, capsicum, broccoli, berries, and tomatoes.
Avoid consuming dairy products or calcium-fortified plant milks alongside iron foods or supplements. Calcium inhibits iron absorption.
Avoid consuming tea and coffee within 2 hours of meals or iron supplements as they contain chemicals that inhibit iron absorption.
Soak legumes for 12 hours before cooking to reduce phytic acid which inhibits the absorption of iron and other minerals.
Supplementation
The most commonly recommended iron supplement is ferrous sulphate (100-200mg), usually given in a single or divided dose every day. However, studies are finding that high-dose iron supplements are very poorly absorbed and very poorly tolerated [1]. Up to 50% of people stop taking iron supplements due to the side effects [1].
When we take high doses of iron, a hormone called hepcidin is released from the liver, which blocks intestinal absorption of iron [4]. This means that out of the 100mg (or more), we may only absorb 10-15mg. So what happens to the rest? It remains in your gut until it’s excreted. This ‘available’ iron is responsible for the commonly reported side effects of constipation, nausea and abdominal pain. It has also been shown to negatively impact the microbiome in favour of pathogenic bacteria, as well as potentially increase gut inflammation and the risk of colorectal cancer [1].
Less is more!
So what can we do about this? Increasing evidence has shown that lower doses of a form of iron called ferrous bisglycinate may be just as effective at bringing iron levels up as higher doses of ferrous sulphate but without the adverse gastrointestinal side effects. [2,3] Ferrous bisglycinate is thought to be more bioavailable, making it a much more tolerable form of iron.
In addition, when taking iron in doses of 60mg or more, it’s recommended to supplement every second day rather than every day [4]. This is due to the hepcidin release, which subsides after 48hrs following a high dose of iron.
Hepcidin is also on a 24-hour cycle and is lowest in the morning and night, therefore I recommend taking iron supplements on an empty stomach (if tolerated), either first thing in the morning or last thing at night.
Why it’s a good idea to work with a practitioner:
If iron levels are low they need to be monitored regularly and the root cause of low iron should be investigated.
The symptoms of iron deficiency are also symptoms of other, sometimes more serious conditions. Incorrectly self-diagnosing can be dangerous.
Haemochromatosis is a common hereditary condition that causes the body to absorb too much iron. Excess iron is a huge problem because the body isn’t great at excreting it. So instead, it gets dumped into the body’s tissues and causes damage. Symptoms can sometimes mimic iron deficiency, so this needs to be ruled out before supplementing.
Taking iron when you don’t need it can add an unnecessary oxidative load to the body, as well as inhibit the absorption of other minerals like zinc and calcium.
I hope this was helpful! If you have any questions or would like to work with me to improve your iron levels, please get in touch.
References:
https://pubmed.ncbi.nlm.nih.gov/24152889/
https://pubmed.ncbi.nlm.nih.gov/24152889/
https://pubmed.ncbi.nlm.nih.gov/29366419/
https://www.sciencedirect.com/science/article/pii/S0098299720300364