Iron & IBD
What is iron?
Iron is a mineral that helps keep our blood and body healthy. It is a major component of haemoglobin, a protein in our red blood cells that carries oxygen from the lungs to all parts of our body. Without enough iron, there are not enough cells to carry that oxygen around our body which then causes fatigue and other affects. Iron is also important for healthy brain development and growth in children, as well as the production and function of cells and hormones.
Where do we get iron?
Iron from food comes in 2 forms: haem and non-haem. Haem iron is found only in animal flesh like meat, seafood and poultry. On the other hand, non-haem iron is found in plant foods such as whole grains, nuts, seeds, legumes and leafy greens. (1).
It is important to note that non-haem iron absorption is enhanced when eating it with animal protein foods (containing haem iron) and foods containing vitamin C. However, food containing phytates (bran-containing cereals) reduces your body’s ability to absorb iron.
What foods are good sources of iron?
Animal sources:
Red meats (beef, lamb, pork)
Fish, especially oily fish like salmon and mackerel
Poultry
Plant-based sources:
Pulses and legumes (beans, peas, lentils)
Spinach
Kale
Broccoli
Nuts
Seeds
How much iron do we need?
Population Group (years) - Daily iron requirements (mg)
Adolescent males (11-18) - 11.3
Adult males (19+) - 8.7
Females (11-50) - 14.8
Adult females (post-menopause) - 8.7
Iron is most needed during periods of fast growth, during infancy, early childhood and adolescence. It is also most needed during menstruation or pregnancy (2).
Iron deficiency
Iron deficiency is one of the most common causes of anaemia around the world, affecting around 500 million people worldwide (3). Iron deficiency can be seen in up to 70% of people with IBD and iron deficiency anaemia can be seen in 1/3 of IBD patients (3).
Symptoms of Iron deficiency and IDA
Fatigue, weakness
Lightheadedness
Confusion
Loss of concentration
Sensitivity to cold
Shortness of breath
Rapid heartbeat
Hair loss
Pale skin
Pica (craving dirt, ice, clay or other non-food items)
In my clinical experience I have seen people still experience symptoms including fatigue and hair loss when iron is at low levels but not deficient.
What causes iron deficiency or IDA?
Iron deficiency in IBD occurs due to:
decreased iron intake from food
difficulty absorbing iron ingested through food, particularly in the duodenum and upper jejunum (common in Crohn’s Disease of these locations but not UC)
bleeding (common in Ulcerative Colitis).
How can we diagnose iron deficiency?
If you are experiencing the symptoms of iron deficiency you can request a blood test from your GP or IBD team to show levels of iron in your blood, stored iron, other iron markers, and if any deficiency is impacting your red blood cells (like haemoglobin).
How can we correct iron deficiency?
Iron deficiency can be supported through over the counter supplements, and increasing the amount of iron from our food.
IDA needs specialist support from the GP/IBD team and can be corrected using prescription iron, iron transfusions or blood transfusions.
Can we have too much iron?
High levels of iron are potentially toxic and can be sudden or gradual. It may be caused by taking high-dose supplements unnecessarily or from having a genetic condition that stores too much iron.
Iron toxicity increases the ‘free’ iron in the body- a pro-oxidant which can cause damage to cells. Early symptoms of iron toxicity may include stomach pain, nausea and vomiting. If left untreated, iron can accumulate in organs causing potentially fatal damage to the brain and liver. Hence, only consume the recommended amounts and consult your GP/doctor before starting any supplements. A study done by Saito, 2014 found that factors such as blood transfusions, alcohol consumption, and uncontrolled increase of iron absorption in patients with a hereditary disease (hereditary hemochromatosis) can cause iron overload.
References
Iron [Internet]. The Nutrition Source. 2022 [cited 13 May 2022]. Available from: https://www.hsph.harvard.edu/nutritionsource/iron/#:~:text=Iron%20is%20a%20major%20component,oxygen%2C%20which%20leads%20to%20fatigue
Iron [Internet]. Bda.uk.com. 2021 [cited 13 May 2022]. Available from: https://www.bda.uk.com/resource/iron-rich-foods-iron-deficiency.html
Prevalence | Background information | Anaemia - iron deficiency | CKS | NICE [Internet]. Cks.nice.org.uk. 2021 [cited 13 May 2022]. Available from: https://cks.nice.org.uk/topics/anaemia-iron-deficiency/background-information/prevalence/#:~:text=The%20global%20prevalence%20of%20anaemia,%25%20in%20non%2Dpregnant%20women