Question:
When your doctor prescribes iron pills, is it important to take them with vitamin C for better effect? And should you avoid caffeine (and maybe other things) either side of taking it?
Answer:
Iron deficiency is one of the most common nutritional deficiencies in the world, with women, children, and people with low dietary iron levels the most likely to experience it. Given the many essential roles that iron plays in our body, maintaining optimal iron status is key.
The good news is we can boost our iron absorption by including or avoiding certain foods and drinks at meal times. This can include choosing both iron-rich foods and supplements.
Iron has many critical roles in our body. First and foremost, it is an essential part of haemoglobin, the component of red blood cells that transports oxygen from our lungs to other parts of our body.
In addition, several proteins and enzymes with significant physical and neurophysiological functions also incorporate iron.
But iron deficiency remains stubbornly the most common form of nutritional deficiency in the world. A recent Irish longitudinal study, published in the American Journal of Clinical Nutrition, found 80% of pregnant women were iron-deficient by the third trimester of their pregnancy.
In New Zealand, a 2007 study found about 14% of urban (Auckland) children aged 6-23 months had iron deficiency.
When it’s prolonged, this can lead to anaemia, resulting in impaired immune function, fatigue, weakness, pale skin and other issues such as headaches and difficulty concentrating. For young children, a lack of iron can lead to impaired learning, memory and attention.
This deficiency can have several causes, including inadequate dietary iron intake, blood loss from heavy menstruation, malabsorption issues such as celiac disease, and even rapid growth in children.
Although optimising our iron intake from food is essential, doctors may sometimes determine that supplementation is needed to resolve the problem.
Two forms of iron are found in food and dietary supplements – haem and non-haem iron. Haem iron is found in animal foods, and is more easily absorbed by our bodies than non-haem iron, found in plant food. Most iron supplements contain non-haem iron, too.
Absorption of non-haem iron is enhanced or inhibited by various foods, as your question suggests, so you can boost the uptake of a supplement by choosing which foods you eat or avoid around the time you take it. For instance, absorption of non-haem iron is significantly boosted by including a rich source of vitamin C with meals or the supplement, as vitamin C promotes iron absorption from the gut. One New Zealand study found that including vitamin C-rich kiwifruit with an iron-fortified breakfast cereal improved the iron status of women with low iron stores, whereas eating a banana with the cereal did not have the same effect.
In addition, meat, fish and poultry, with their haem iron and other nutrients, also promote iron absorption from other foods at meal times. So, taking your supplement alongside a dinner containing a rich haem iron source – whether lean red meat, chicken, seafood or an egg – is a great idea.
Conversely, tea and coffee contain tannins that bind to iron and reduce its absorption. Unfortunately, even caffeine-free tea and coffee still contain tannins, so it’s best to avoid drinking tea or coffee for about an hour either side of meals or taking your supplement.
Calcium also inhibits iron absorption, so timing those big, milky flat whites and smoothies, or yoghurt or cheese snacks, to avoid clashes with peak-iron consumption is wise.
To sum up, although supplements can be an effective way to address iron deficiencies, their absorption can be influenced by other foods and beverages. But by making strategic food choices and timing supplement intake wisely, you can improve absorption and support overall health.
