Fibromyalgia, iron and neurotransmitters

You might think that functionally low iron would contribute to the pain and fatigue of fibromyalgia through its effect on the oxygen carrying capacity of the blood, which would not be incorrect. But as this study just published in the European Journal of Clinical Nutrition reveals, there is another very important effect of suboptimal iron levels.

"Iron is essential for a number of enzymes involved in neurotransmitter synthesis. Analysis of cerebrospinal fluid in fibromyalgia syndrome (FMS) has shown a reduction in the concentration of biogenic amine metabolites, including dopamine, norepinephrine and serotonin. This study aimed to investigate the association of ferritin with FMS."

Ferritin, a protein that stores iron, is the most accurate single quantifier for iron stores in the body. Adequate iron is mandatory for the production of neurotransmitters including dopamine and serotonin (one of the reasons why depression occur around the time of menses). What did their data show?

"...having a serum ferritin level <50 ng/ml caused a 6.5-fold increased risk for FMS."

Doctors (and everyone), notice the serum ferritin level. Many practitioners are not aware of other research showing that the common laboratory reference ranges for ferritin are too low and that 50 ng/ml should be the cut-off point. Additionally, there are a number of mechanisms by which suboptimal dopamine and/or serotonin production can affect the experience of pain and fatigue with FMS.The authors' conclusion is consonant with the existing evidence:

"Our study implicates a possible association between FM and decreased ferritin level, even for ferritin in "normal" ranges [quotation marks added]. We suggest that iron as a cofactor in serotonin and dopamine production may have a role in the etiology of FMS."

If there is a question about iron, have your serum ferritin checked (at least) and make sure that it is not lower than 50 ng/ml.