I'm copying some text here from the other site - it took me a long time to find it so I don't want to lose it again! "Are men and women really that different in CFS? Yes. About 40-50% of all the metabolites that we measure in our method have a different normal concentration in males and females. This is not all related to testosterone and estrogen. Literally hundreds of metabolites are tuned to different concentrations in men and women. At the pathway level, we found that men and women shared 9 (45%) of the 20 biochemical pathways that were disturbed in CFS patients. Eleven pathways (55%) were more prominent in males or females. We find that to do metabolomics properly, you need to have an adequate number of age- and sex-matched controls. If healthy males and females are lumped together as controls, the power to see metabolic differences in CFS and many other diseases is much decreased. Likewise, the metabolism of a 25-year old male is different from a 35-year old male, and categorically different from a 25-year old female. In each decade of life there are many metabolic changes that occur as part of normal development and aging. When proper age- and sex-matched controls are used, metabolomics is one of the most powerful new tools available to physicians and scientists to study chronic complex disease." I think it's really important that everyone see this, for example so that they can bear it in mind when thinking about trying something that someone of a different gender (or age) is benefiting from. I don't know if I'm allowed to post a link to PR, but this is the name of the thread: "Professor Ron Davis's response to Naviaux study, including Q and A with Dr Naviaux".