Well, correlation does not necessarily imply causation, and given that reflexology is only a placebo treatment, I think you can conclude it is coincidence. No effect = no side effects.
Colds are caused by viruses, not foot massages. And no foot massage is going to release 'toxins' and bring on illness faster. That is pseudoscientific garbage. http://www.theness.com/neurologicablog/?p=452
Question for Britta: What toxins are you referring to and what is the evidence that supports your claims?
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EDIT: @onlymatch4u, yes it is a placebo only. If you think I'm wrong, I'm willing to make a correction, but I only make corrections based on the provision of robust, peer reviewed scientific data. So go ahead and post your evidence and change this skeptic's mind. Otherwise your rant is worthless.