Hi Purl,
when I first started 180D, I got heart palpitiations which were clearly linked to cafeine (coffee) intake. I didn’t use to get that before, but now I know there is a fairly low limit on how much coffee I can drink, especially in times of stress (deadlines at work etc.). I don’t know if that’s my body showing me more clearly what it does and doesn’t want, or if it’s the cortisol thing and I really “only” have a cortisol overdose rather than a coffee overdose (cafeine increases cortisol production, from what I gather). Personally, I find not drinking lots of coffee quite difficult…
Anyway, I share this in case it could be a lead, although clearly palpitaions can have all sorts of reasons.