The deep-fried Mars bar, a nutritionist’s nightmare that surfaced in Scotland about a decade ago, is now an established part of the Scottish culinary scene.

Dipped in batter and then cooked in hot oil, the Mars bar is now on sale in more than a fifth of Scotland’s 627 fish-and-chip shops, it says.

The average sale is 23 bars per shop per week, but some shops say they sell up to 200 a week, it records.

The deep-fried Mars bar first surfaced in news reports in 1995, reputedly originating in the eastern city of Aberdeen.

Promoters of Scottish tourism — aghast at this damage to their efforts to highlight Scotland’s history, culture and landscape — joined with middle-class foodies in deriding the DFMB as media hype.

But this is untrue, say authors David Morrison and Mark Pettigrew of the Greater Glasgow NHS Board, who contend the snack is “deep and crisp and eaten.”

“Scotland’s deep-fried Mars bar is not just an urban myth,” they say.

Health experts have condemned the deep-fried Mars bar as an artery-clogging catastrophe.

Scotland is already ranked as the country with the highest rate of chronic heart disease in Western Europe, a position that owes itself to cigarettes and alcohol as well as a poor diet and a love of sugary foods.

Critics should take heart, though.