There can be many things that cause rashes, from allergies to stress-related rashes like shingles. I'm not sure about your cutting right back on caffeine and sugar giving you a rash - I would have thought you'd be more likely to break out in spots as your body went through a kind of detox, but then again I could be wrong.
Have a look at this, it may help http://familydoctor.org/545.xml
Hope you manage to find out what's causing it!
Tracey
.•:*¨¨*:•.Tracey.•:*¨¨*:•.
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