While medical practice generally turns a blind eye to the value of nutrition in health, it has at least embraced the importance of certain specific nutrients including iron. Iron is important for the manufacture of haemoglobin ” the protein in the red blood cells responsible for carrying oxygen around the body and delivering it to the tissues. Iron deficiency can lead to anaemia, which can lead to symptoms which include fatigue and low mood.
What is less well recognised about iron is that it participates in the reactions that generate energy within the body. It is possible for individuals to become iron deficient without becoming anaemic. However, iron deficiency in the absence of anaemia can still cause individuals to suffer symptoms such as fatigue and low mood. This is particularly common in women of child-bearing age, particularly as a result of loss of iron via menstrual blood each month.
The relationship between iron status, anaemia and mental function was recently studied in a group of 149 women aged 18-35 years. At the beginning of the study, women were classified as being either iron-sufficient, iron deficient and anaemic, or iron deficient in the absence of anaemia. All women were put through their paces with 8 tests of mental function.
At the beginning of the study, the iron-sufficient women performed better and completed the mental tasks more quickly than the iron deficient anaemic women. Cognitive performance and task completion results among the iron deficient non-anaemic women fell between the iron sufficient women and iron deficient anaemic women.
Women who were iron deficient were then treated with iron supplements for a period of 8 weeks. At the end of the study, a significant improvement in serum ferritin was associated with a 5-7 fold improvement in mental function. The authors of this study concluded, “Iron status is a significant factor in cognitive performance in women of reproductive age”. They went on to add that the severity of iron deficiency affects accuracy of cognitive function over a broad range of tasks.
In medicine, we commonly check for anaemia. However, we much less commonly check for iron status. I do think it is important for individuals to be alert to the fact that iron deficiency in the absence of anaemia have adverse effects on health and wellbeing.
In my experience, the best test for iron levels in the body is what is known as the ‘serum ferritin’. It is my experience is that ferritin levels of less than about 50 are generally associated with symptoms such as fatigue, low mental energy and low mood. As I said, women of child-rearing age are at risk of this. This is particularly true for vegetarians and vegans in my experience.
Those not wishing to stoke up on liver and red meat may wish to contemplate supplementation. Many iron supplements are not well absorbed, however. One that I find useful in practice is Floradix “a liquid form of iron that is available from most health food stores.
1. Murray-Kolb LE, et al. Iron treatment normalizes cognitive functioning in young women Am J Clin Nutr, 2007;85(3): 778-787