Iron is needed in the body for many functions which include transporting oxygen in the blood, being a major component of haemoglobin and therefore red blood cells and of many enzymes which are needed for energy production.
Types of Iron
- Haem Iron; Is only found in animal products so things such as beef, lamb, poultry an fish. Offal such as kidneys and liver are particularly high in Iron. Haem iron is only 40 - 45% of the Iron contained in animal products, the reset of it is non-haem iron.
- Non Haem Iron; Can be found in animal products too but is also found in plant food such as dried beans, lentils and whole grains.
Recommended daily intakes
- Young children both boys and girls - between 8 - 15mg depending on age and gender
- For women aged between 19 - 50 - 18mg
- For women ages 50 and above - 8mg
- Pregnant women - 27mg
- Men aged 19 and over - 8mg
Iron Absorption rates
Our bodies are designed to absorb the Haem iron from animal products better than non-haem iron. This is one of the reasons why vegetarians are more likely to develop anaemia than someone who eats meat. The non-haem iron just isn't as available to our bodies as haem iron is. The absorption rates for haem Iron is approximately 20-30% of the total Iron in a product, compared to between 5-12% for non-haem Iron.
Factors that affect Iron Absorption
One of the most significant factors that influence Iron absorption is the amount of Iron that you already have stored in your body. The body stores Iron in various places such as Liver, spleen, bone marrow and skeletal muscle to name a few. If your Iron stores are high, then your body recognises that it doesn't need much more so will absorb less from the foods you are eating. Conversely when you have low Iron stores, your body will recognise that it needs to absorb more of it.
Dietary factors that Boost Iron absorption
- Vitamin C - if you are taking a Iron supplement always make sure to take it with Vitamin C as this will greatly increase it's absorption capacity. Vitamin C foods include - Oranges, leafy green vegetables, kiwi fruit, strawberries, papaya, guava, broccoli.
- Animal protein - The mix of both haem and non-haem Iron in animal products greatly increases the absorption capacity of Iron form plant sources. Such as having a steak with steamed spinach
- Cooking - For the majority of cases cooking helps to significantly increase the amount of available non-haem Iron from vegetables. For example the body can only absorb 6% from uncooked broccoli compared to approx. 30% from cooked.
- Vitamin A - can help to released stored Iron within the body so a deficiency in Vitamin A could lead to anaemia.
Dietary factors that reduce iron absorption
- Soy proteins can reduce the rate of absorption of non-haem iron from both plant and animal sources.
- Tannins, a naturally occurring polyphenol, contained in tea, coffee, chocolate and wine reduce Iron by binding the Iron and excreting it from the body so always have your tea or coffee away from your meals.
- Anti-nutrients such as Oxalates and Phytates reduce the absorptive capacity of Iron but doesn't diminish it completely. Oxalates are found in dark leafy greens such as spinach and beet greens and phytates are high in whole grains, nuts, seeds and legumes
- Both calcium, magnesium and phosphorus reduce the absorption capacity of non-haem iron.
Sources of Iron
Highest Haem Iron Sources
- Oysters & mussels
- Beef, lamb, veal
- Fish (halibut, haddock, salmon, tuna)
Highest Non- Haem Iron Sources
- Cooked Spinach - Raw spinach is high in Oxalates and it binds to the Iron so the Iron in raw spinach is very low.
- Seeds - pumpkin seeds, sunflower seeds
- Firm tofu
- Beans & lentils -chickpeas / garbanzo beans, white beans, red kidney beans, soybeans, black beans.
- Baked potato with skin - without skin, a potato’s iron is minimal
- Prune juice
- Dried fruits - raisins, apricots
- Nuts - cashews, almonds, pistachio
Photo - https://www.healthline.com/