This page seems to suggest that a Krispy Kreme donut (assuming that the 52g is for one donut) is about 220 kcal. http://www.krispykreme.co.uk/uploads...ional-Info.pdf
That's about the same as the single piece of peanut butter toast that I ate this morning.
Surely it should be possible to have a Krispy Kreme donut breakfast, but still easily fit within a moderate daily calorie total. Not that I'd advise it, but starting with a Krispy Kreme donut does not necessarily imply a non-diet day.
Surely as well as calories though you are considering the fat content of a food?
(this won't tabulate properly I know)
Item Serving Size Calorie Count Grams of Fat
hot cross bun 70g 205 3.9
scone 70g 225 7.6
So the same size portion, only 20 more calories, but almost double the amount of fat!!!
That's why a donut won't be good for breakfast