I also enjoy a pretty healthy diet/lifestyle - low-salt, low-fat, fruits, veggies, plenty of fiber, regular exercise... I find that my body reacts very badly if I "treat" myself and indulge throughout the day in whatever everyone else consumes so freely. No such issue if it's just a single meal.
I need to taper in (ie, the Holidays are a good example). High salt, high-fat meals are especially hard hitting. I can counter this with lots more water, fiber for example. I also know that if I remained on these richer diets, eventually my body wouldn't react so strongly but I would also need to make other dietary changes. Damon Gameau admits he did not make other changes to his diet.
The experiment was a non-stop, high-dose, sugar binge (40 tsp is incredibly high) that went from 0-100 mph in a microsecond.