A solitary Englishman was sitting in a Chinese restaurant the other night facing a table of seven young Italians when, all of a sudden, the head of the big table noticed something about the Anglo-Saxon and exclaimed: Look! They all turned around and there were murmurs of shocked surprise.

A litre! All to himself!

Indeed, the object of such wonder was at that moment working his way down a bottle of Fontana Candida white, as tall and slim as a skittle. His opposition, on the other hand, was fielding one half-litre of wine, two small bottles of beer and an enormous plastic vessel of mineral water.

The scene epitomised what to many a foreigner is a tantalising mystery: why do the Italians drink, at least apparently, so sparingly? Or, more accurately, why do Romans and southern Italians appear abstemious, because in parts of northern Italy they can interviewees smartly pointed out drink anybody under the table. One barman explained: Up in Friuli, they dont say Lets go for a coffee in the morning, but Lets go for a wine.

At first sight it is a puzzle because Italians down more wine than any other nation in the world, according to a report for a wine-expo in Bordeaux last year. Annually they put away nearly 60 litres of wine a head, ahead of France (58 litres) and Argentina (36). Nowadays they sip more wine than ever. Altogether, some 25 million lips are at work, among them 16 million in a new category who now consider it a status symbol to be seen drinking wine, a fashion catching on quickly. A decidedly new factor is a dynamic clan of young people, as well as members of the professional classes. The statistical agency CENSIS says such drinkers now have good cellars of their own, buy the dearer bottles and tend to drink more in public, hence the new craze for wine bars, the number of which has shot up by 40 per cent in the last five years.

As for beer, Rudi Peroni, president of Assobirra, the brewers association, said that a mere six per cent of Italians drink it daily and some 30 per cent now and again. Italians quaff double what they did 25 years ago, but even so, their average yearly intake is only 17 litres a head, mainly in summer, which qualifies them for the European booby prize. They also pour vodka, rum and whisky tempters once virtually unknown in the vanished Italy of mass poverty down their throats (in that order), and it all adds up to a river of liquid.

Where, then, does it all go? Why do young Italians in the pubs seem to nurse one pint for a whole evening, to the despair of publicans? Why does a whole party in a trattoria get through only two or three bottles between them? Why can huge presidential guardsmen the corazzieri be seen treating themselves to glasses of sugared milk in late-night bars?

The answer seems to boil down to habits born of tradition and to what is seen to be seemly. Several people questioned, including a doctor, Donnella Costantini, pointed out that for centuries wine has been seen in Italy not as a frill but as a part of the diet liquid bread it has been called. A wine writer, Franco Ziliani, editorialising in Winenews, spelt out the consequences: most Italians, he said, drink in a reasonable, moderate, healthy, calculated way, one or two glasses at lunch and dinner, implicitly at home, invisible to foreigners. He was protesting furiously against what he thought was an absurd new law lowering the maximum allowed alcohol content in a motorists blood to one glass. Any Italian, he fumed, could safely handle more than that. Or as gym-fit Luca Camero in a discreet bar in Via dei Serpenti put it: We drink a lot, and every day, but not huge amounts, tanto ma non tantissimo, not to excess like the English. They work a lot during the week and have to let off steam at the weekend. We dont.

Marco Brocchi, a colleague in Via Cavour, put it like this: The rhythm of life in the south is more relaxed. Then its hot in the south. Why warm up the blood more with strong southern wine, which can only be taken in small doses anyway? Brocchi unwittingly adumbrated a startling remark by a Sardinian waiter in Campo de Fiori that the Italians drink little in public out of fear. He meant the nation-wide horror of public disgrace, of not maintaining the mandatory bella figura, a dread that comes out in the look of disgust reserved in Rome hostelries for lurching British sing-along lager louts, who are unaware of the social stigma attached to drunkenness.

Theres a social brake to drinking too much, observed Brocchi. If a group of friends goes out to a bar, its to spend a pleasant evening together, to talk, not to drink for the sake of it. If one of them does, he ruins the evening for the rest.

An Italian-Irish TV producer had an earthier explanation of why young Italians rarely behave like British weekend drunks. They prefer to get laid than to get pissed. They cant do both, can they?

But why were other southern Europeans the Spanish, the Portuguese, the Greeks, the southern French not as well behaved as the Italians? Nobody had an idea. Could the Italians be more civilised? They would never say it themselves of course, but it would be a logical proposition.

No wonder the seven looked round at the barbarian behind them.