I'm not sure if my previous post got thru', so apologies if you have already received it.
I heard that wearing a fit-bit can warn the wearer of the onset of "dumping" by making the wearer aware of an increase in their heart rate. Which would mean you could take evasive action before it took hold. If you have used this method, I would be really interested in knowing which model of fit-bit you have.
There seems to be so many different ones on the market.
Many thanks