The doughnut (or donut) began life in Holland as 'oly koeks' ('oil cakes') made by dropping the leftovers from bread-making into boiling oil.
The earliest use of the word 'doughnut' in print was in 1809 in Washington Irving's History of New York.
The first doughnut cutter was patented by John Blondell in 1872.
The hole in the doughnut is attributed to US sea captain Hanson Crockett Gregory, who, according to one legend, poked out the soggy centres of his doughnuts so he could slip them over the spokes of his ship's wheel
A more reliable version is that the hole in the middle was added to ensure regular baking. Whatever the truth is, Gregory is said to have invented the hole in 1847 and a commemorative centenary plaque was placed on his house in Rockfort, Maine, in 1947.
According to the International Federation of Competitive Eating, the world record for doughnuts is 48 glazed doughnuts in 8 minutes by Eric Booker. Booker also holds other eating records, including one for eating 38 hard-boiled eggs in 10 minutes.
Ten billion doughnuts are made in the USA every year.
According to a study at Northwestern University in Chicago in 2008, two areas of the brain were stimulated when hungry volunteers were shown photos of Krispy Kreme doughnuts
The same response, however, did not occur after participants had stuffed themselves with up to eight of them.
The research was conducted with functional magnetic resonance imaging brain scans while volunteers were shown pictures of doughnuts
The paper, which was published in the journal Cerebral Cortex, was entitled "The Spatial Attention Network Interacts with Limbic and Monoaminergic Systems to Modulate Motivation-Induced Attention Shifts".