Pete’s Blog – October 2020

Importance of Iron

I have written of late on the importance of eating adequate protein on a daily basis. Protein is an important macronutrient and we all need to include good sources of lean protein at each meal to ensure that we eat well each day. Most sources of protein also contain an important micronutrient, iron. Iron is a mineral that is found in a range of foods. It helps to transport oxygen around the body, making it essential for life! It is also important for producing energy, optimal immune function, and storing oxygen in our muscles (this is what gives muscles their red colour!) 

Despite iron being found in both animal and plant based proteins, not all proteins are created equally when it comes to the quantity and quality of iron that can be obtained from different protein sources. Having an awareness of the daily amounts of iron required by males and females, as well as which foods contain not only the most amount of iron but also the most easily absorbed will go a long way to ensuring that you avoid developing iron deficient anemia. If you are thinking of changing to a more plant based and/or vegan diet I would encourage you to do your homework before making the change to ensure you are getting adequate amounts of all of your macronutrients and also important micronutrients such as iron. 

Wholegrain cereals, meats, fish and poultry are the major contributors to iron intake in Australia but the iron from plant sources is less bioavailable. The form in which iron is consumed will affect dietary intake requirements as not all dietary iron is equally available to the body. The factors that determine the proportion of iron absorbed from food are complex. They include the iron status of an individual, as well as the iron content and composition of a meal. Iron in foods can come in two general forms - as haem or non-haem iron. Iron from animal food sources such as meat, fish and poultry may be either haem or non-haem whereas the iron in plant sources such grains and vegetables is non-haem. The haem form is more bioavailable to humans than the non-haem.

The presence of other nutrients such as vitamin C and organic acids such as citric, lactic or malic acid can increase the absorption of non-haem iron. Consumption of meat, fish and poultry can also increase non-haem iron absorption from plant foods consumed at the same time. In contrast, some other components of the food supply such as calcium, zinc or phytates (found in legumes, rice and other grains) can inhibit the absorption of both haem and non-haem iron, and polyphenols and vegetable protein can inhibit absorption of non-haem iron. High iron intakes can, in turn, affect the absorption of other nutrients such as zinc or calcium.

Functional indicators of iron deficiency may include reduced physical work capacity, delayed psychomotor development in infants, impaired cognitive function, impaired immunity and adverse pregnancy outcomes. However, as these are difficult to relate directly to a specific dietary intake, biochemical indices are generally used in estimating dietary requirements.

How much iron do I need?

For example, a man could get his RDI for iron by simply having a serve of wholegrain iron-enriched breakfast cereal, a serve of red meat and handful of nuts in one day.

Women in their reproductive years have a much higher iron requirement than men, due to the loss of monthly blood. As such they can find it difficult to meet their daily requirements with food alone, which means they also have a higher risk of iron deficiency.

Women are advised to have their iron levels regularly checked by their GP, who may recommend further dietary measures or an iron supplement.

Where do I find iron in foods?

There are 2 types of iron that we can get from foods:

·       Iron from animal sources is known as haem iron

·       Iron from plant-based sources is called as non-haem iron.

Haem iron is absorbed more efficiently and in a different way to non-haem iron.

How can I improve my iron intake?

Some foods can help our bodies absorb iron, while others can inhibit it.

To ensure your iron is being absorbed it is recommended that you:

• eat foods high in vitamin C with foods that contain iron

• cook your plant foods to improve the amount of available iron

• avoid having tea, coffee or calcium during or directly after having a source of iron

• speak to your doctor about any possible dietary interactions with your medications or herbal supplements that could impair iron absorption

• ensure that you only take iron supplements under the advice of a GP, as too much iron can also be harmful.

(Source – nutritionaustralia.org)