Diet Rich in Iron
by Sue Kira, Naturopath & Clinical Nutritionist
– Benefits of good levels of iron
– Not all iron is created equal
– Things that block iron absorption
– Foods and substances to boost iron absorption
– Signs and symptoms of iron deficiency
– Common reasons for iron deficiency
Iron is found in every living cell of the body
In the making of hemoglobin, Iron combines with copper and protein which makes the red in red blood cells. Iron is part of what builds the quality of blood to help with resistance to disease and stress. Iron is also part of what makes myoglobin which helps to transport oxygen to muscles – and myoglobin is part of the chemical reaction in muscle contraction.
Iron is stored in the liver, bone marrow, spleen and blood. Iron is used very efficiently in the body. Daily iron requirements vary but there is increased need during menstruation, hemorrhage, rapid growth phases or whenever there is blood loss.
Additional iron is needed during pregnancy as the developing baby builds its own blood supply. Infections and peptic ulcers can also deplete iron reserves, as well as blood donations. Deficiencies of B6 and zinc can mimic an iron deficiency.
Low iron can also be the result of: hemolytic (red cells destroyed too early); aplastic anemia (bone marrow doesn’t make enough red cells); early hepatitis; or a vegetarian diet where people don’t eat enough green vegetables or consume too many phytates from grains.
Excess iron can occur with metabolic issues and genetic conditions such as haemachromatosis, or with conditions such as liver cirrhosis, diabetes or pancreatic disorders, and for those who drink lots of red wine.
It is recommended you get your blood checked to see if you need to increase your iron intake, especially if you are pregnant, a vegetarian/vegan, have a digestive disorder, an auto-immune condition, or you feel tired – particularly after exercise.
A diet rich in iron containing foods as well as concurrent vitamin C intake can help to restore iron levels in the blood, depending on how depleted your levels are. If very low, you will need supplementation and/or iron infusions (injections) prescribed by your doctor until levels are normal and then an iron rich diet to help maintain levels.
If you repeatedly get low iron even on an iron rich diet, then there is something going on in your body that needs further attention. Seek medical attention if this happens to you.
Benefits of good levels of iron
Anaemia is caused by a low production of red blood cells and haemoglobin, which results in low levels of oxygen reaching the cells throughout the body. Anaemia usually results in low energy, but it can affect many areas of the body, including low immunity and poor brain function.
The World Health Organization (WHO) estimates that approximately half of the 1.62 billion cases of anaemia worldwide are due to iron deficiency, while the other half are due to genetic factors.
Apart from genetic abnormalities, anaemia can be the result of inadequate intake of iron, impaired absorption or transport to the cells, heavy menstrual periods or other chronic blood loss. Apart from fatigue, anaemia can result in diminished work or exercise capacity, impaired temperature regulation, immune dysfunction, gut disturbances, and neuro-cognitive impairment, such as mental fatigue and lack of focus.
Iron is the oxygen carrying molecule in the blood and it also helps with the metabolic enzyme processes that the body carries out to digest proteins and absorb nutrients from food. This is the reason why an iron deficiency causes exhaustion and other symptoms of sluggishness.
Iron deficiency commonly shows up in symptoms like low concentration, mood changes and trouble with muscle coordination
Helps support cognitive function
Iron is needed to support brain function because it carries oxygen to the brain. About 20% of all the oxygen in the body is used by the brain even though it weighs only 2% of the body weight. This is why an iron deficiency can impair memory or other mental functions. In infants and children, a deficiency can cause psychomotor and cognitive abnormalities that may lead to learning difficulties.
Supports development and growth of the young
Iron deficiency can delay normal motor function, which is the ability to connect thoughts with activities and movement as well as mental functions like learning and processing new information.
Supports a healthy pregnancy
Iron deficiency during pregnancy increases the infant’s risk of low birth weight, premature birth and impaired cognitive and behavioural development. All pregnant women should eat plenty of iron-rich foods and also take supplemental iron if their iron levels are not optimal (top end of the normal reference range).
Supports a positive mood
Iron is required for proper neurotransmitter function, so a positive mood requires good levels of iron. Your mood relies on a balance of neurotransmitters such as serotonin, dopamine and other neurotransmitters that cannot be synthesized properly in the brain when oxygen levels are low. Iron carries oxygen to the brain, which is why low iron can lead to low mood, poor sleep, low energy and a lack of motivation.
Prevents restless leg syndrome (RLS)
Iron deficiency is one of the causes of ‘restless leg syndrome’, which can lead to major sleep disturbances. Iron helps to transport oxygen to our muscles which helps to minimise the risk of muscle spasms and pain. Magnesium is also important for RLS.
Not all iron is created equally
Animal foods contain a type of iron called heme iron, which is more absorbable than the iron found in plant foods, called non-heme iron. The heme iron from meat, poultry and fish is absorbed two to three times more efficiently than non-heme iron from plants. If you are a vegan or vegetarian, you need to be careful about getting enough iron and may need to take an iron supplement.
Things that block iron absorption
Substances that inhibit iron absorption include: foods contain high amounts of calcium (e.g. dairy); polyphenols (tea & coffee); phytates (grains & legumes & some nuts and seeds unless soaked/sprouted) and oxalates (spinach and chard). Some say the level of inhibition is of little concern, but it is still useful to know, especially if you struggle to maintain good iron levels.
Other inhibitors include: minerals that compete with iron such as zinc, calcium, copper, magnesium and phosphorus; herbs including peppermint and chamomile; fibre; cocoa; insufficient vitamin A; soy proteins; and intestinal permeability which affects the absorption of iron.
Foods and substances to boost iron absorption
Heme, which is the blood from animals, is easier to absorb than non-heme which comes from leafy green vegetables. Thus poultry, pork, fish, and beef in particular, are excellent sources of iron. When these proteins are combined with vegetables, they enhance the body’s ability to absorb the non-heme iron from those vegies.
Vitamin C helps in the conversion of ferric to ferrous iron. It’s also important to have a balance of calcium, phosphorus and iron. This is because excess phosphorus affects iron absorption, unless there is sufficient calcium present – which combines with the phosphorus to free up the iron for use by the body.
In general, if you eat a variety of whole-foods that include grass-fed meat, free-range poultry and eggs, as well as plenty of different fruits, vegetables and beans, you will obtain good amounts of iron.
For vegans and vegetarians, try to combine foods that are naturally high in vitamin C with the rest of your meal, particularly as vitamin C helps your body to absorb the non-heme iron.
Good sources of vitamin C rich foods include leafy greens, beans, bell peppers (capsicum), kiwi fruit, oranges, grapefruits, blueberries, all cruciferous vegetables like Brussels sprouts or broccoli, cantaloupe/rockmelon and snow peas.
Cooking also increases the amount of available non-heme iron in vegetables. The body absorbs five times more iron from cooked broccoli compared to raw broccoli.
Signs and symptoms of iron deficiency
Symptoms of iron deficiency are: easily fatigued, especially after exercise: decreased resistance to infections and pale skin; paleness of the lines in the palms of the hands; and paleness of the lower conjunctiva of the eyes when pulled down gently. Brittle nails and lackluster skin can also be signs of anaemia.
- Chronic fatigue or low energy
- Paleness or yellowing of the skin
- Shortness of breath
- Abnormal heartbeats
- Signs of a hormone imbalance
- Trouble exercising or fatigue after exercise
- Muscle weakness
- Changes in appetite
- Trouble getting good sleep
- Changes in weight
- Trouble concentrating, learning, remembering things
- Sores on your mouth or tongue
- Mood changes
Common reasons for an iron deficiency
- vegetarian or vegan diet
- exercise a lot
- pregnant or breastfeeding
- kidney failure, undergoing or have undergone dialysis treatment
- gastrointestinal disorders that can limit your ability to absorb nutrients, such as celiac disease, Crohn’s disease or ulcerative colitis
- antacids, as these contain calcium that can prevent iron absorption
- surgery or loss of blood for any reason, including donating blood
- infections, as the ‘bugs’ live off our iron
The following list provides the recommended daily allowance in milligrams of iron for different age groups and sexes. Then a list follows of foods that are good sources of iron. By using the two lists, you can calculate what foods you need to maintain the RDA of iron.
- Children ages 4 to 8 need 10mg
- Children ages 9 to 13 need 8mg
- Women ages 19 to 50 need 18mg
- Pregnant women need 27mg
- Breastfeeding women need 20mg
- Men ages 19 to 50 need 8mg
- Men and women over 50 need 8mg
- Liver (beef, lamb or chicken): ½ cup = 9.5mg
- Duck or chicken: ½ breast = 3.7mg
- Grass Fed Beef: 3oz (85g) = 2mg
- Lamb: 3oz (85g) = 1mg
- Sardines: 1 can = 2.7mg
- Egg: 1 large = 0.9mg (0.5mg from the yolk)
- White beans (cooked): 1 cup = 6.6mg
- Lentils (cooked): 1 cup = 6.5mg
- Spinach & other leafy greens: 1 cup = 6.4mg (but needs to be cooked to lower the oxalic acid)
- Kidney beans (cooked): 1 cup = 5.2mg
- Chickpeas (cooked): 1 cup = 4.7mg
- Pumpkin Seeds: ¼ cup = 0.5mg
- Cherry and fruit juice: ½ cup = 0.4mg
- Dried apricots: ½ cup = 2.7mg
- Dried peaches: ½ cup = 5.7mg
- Other good sources of iron include beetroot, coconut/coconut water, sweet potato, broccoli, asparagus, cashews, mustard seeds, pistachios, raisins, coriander seeds and walnuts.
While it is preferable to get iron from your diet, there are circumstances when additional supplementation may be required, for example, for a pregnant or a breastfeeding mum, particularly if vegan or vegetarian.
Generally the body self regulates the amount of iron absorbed from food so that we rarely have too much. But you can get an iron overload in certain situations, such as with a genetic condition called Haemachromatosis.
The main way we get an excess of iron is from supplements or iron injections, especially if the levels in the blood are not monitored. It is common for children to get an overload of iron by drinking too much of the popular fruity tasting sweetened elixir iron tonic, purely because they like the taste.
The side effects of taking iron supplements (even if not an excessive amount) can be constipation, which is why many choose food sources to rebuild their iron.
A safe supplement that I prescribe for clients because it doesn’t create constipation is liquid chlorophyll drink. While it is not so good for severely low iron levels, liquid chlorophyll helps the body to naturally restore iron levels slowly, yet is faster than food alone and was particularly good for my vegan clients who couldn’t use liver (for example) as a booster.
A point to note is that where there is an iron deficiency, there is commonly concomitant low levels of vitamin B12, so do get both of these checked when testing for iron. When testing, it is best to get your full ‘Iron Studies’ done that look at various factors related to iron.
Important: Before you commence a new diet, see your medical or health care professional for qualified guidance about what foods and supplements are best for your body. While on the diet do not stop any medications or supplements previously prescribed unless advised otherwise by your medical or health care professional.
Note: During the early stages of a new diet, you may experience symptoms such as fatigue, headaches or body aches, which may occur because your body is detoxifying. However, if you are unsure about a symptom at any time, check immediately with your medical or health care professional.