The UK media are today reporting that eating dark chocolate, which has a high cocoa content, may be an effective treatment for ME/CFS.
The story is based on the results from a small pilot research study carried out at Hull and York Medical School.
But these are preliminary findings involving only a very small number of people with ME/CFS. So they have to be viewed with caution.
From a theoretical point of view, dark chocolate contains chemicals known as polyphenols, which improve the levels of an important brain chemical transmitter called serotonin. And while there is evidence from a number of research studies to show that disturbances in serotonin may be present in ME/CFS, this research also indicates that different types of serotonin disturbance may be present. This latter finding may help to explain why selective serotonin reuptake inhibitor (SSRI) drugs such as Lustral/sertraline and Cipramil/citalopram , which increase serotonin activity in the brain, appear to be effective in some people with ME/CFS but only cause very unpleasant side-effects in others. [
More information on serotonin disturbance in relation to ME/CFS can be found in the section on central nervous system research (5:4) in the July 2007 edition of MEA guidance for health professionals: ‘ME/CFS/PVFS – An Exploration of the Key Clinical Issues'.
Cocoa also contains other chemicals and nutrients – eg magnesium, potassium, dopamine, tryptophan – as well as antioxidants that have been linked to ME/CFS. So there are other possible explanations as to why it could be of benefit.
From a practical point of view there shouldn't be any harm in people with ME/CFS taking a small amount of dark chocolate (45g was the dose used in the research study) each day to see if it helps – provided chocolate doesn't exacerbate pre-existing medical problems such migraine. However, we would not advise people to start eating large quantities of dark chocolate.
If anyone has any feedback on the use of dark chocolate this can be forwarded to the MEA via: email@example.com
More information on this Hull York study can be found in an article – Behind the headlines: dark chocolate and ME – on page 15 of the April 2007 issue of the ME Association's quarterly ME Essential magazine.
Dr Charles Shepherd
Honorary Medical Adviser, ME Association