LIFT IRON AND EAT IRON!
There are two forms of dietary iron. One is derived from plant sources, as well as eggs and dairy, and is in the non-heme iron form (Fe3+). The other type comes from animal sources, and is in the heme iron form (Fe2+). Interestingly, only ~45% of the iron in meat is heme iron, whereas the remaining ~55% is non-heme iron.
Heme iron is more bioavailable, and therefore readily absorbed into our bloodstream (around ~30-50% of heme iron within a meal will be absorbed). Unfortunately, non-heme iron is far less bioavailable, and absorption can be as low as ~5% in some individuals. However, the bioavailability of non-heme iron can be increased when the food is paired with a Vitamin C source!
Vitamin C is an antioxidant found in most fruits and vegetables and acts as an electron donor to convert Fe3+ iron into the biologically available Fe2+ form. This is great considering that heme iron in our blood is responsible for binding and transporting oxygen and carbon dioxide throughout the body… and no one wants to be short of breath!
With this in mind, particularly if you’re vegetarian, follow a plant-based diet, or don’t regularly consume meat, it's best to combine your non-heme iron and vitamin C sources together. A few examples could include adding capsicum to your spinach and kale salad, having fresh fruit with your oatmeal, or plenty of vegetables with your beans and legumes!
Also, take note that there are many nutritional compounds found in various foods (of plant and non-plant origin) which have the potential to impair iron absorption. A few of these compounds include calcium in dairy products, tannins found in tea and coffee, oxalates in spinach and kale, and phytates found in wholegrains, legumes, nuts and seeds. However, our general recommendation is to not get too pedantic and worry about whether or not all of your iron is being maximally absorbed... because it’s partly outside our control. Although, in saying that, we would recommend not going out of your way to drink a big glass of milk or coffee with your salad or bean burrito.
Best way to check your iron status? Get a blood test!