Never has being dry been more fashionable. Sobriety is in vogue – and in Celebrityland, everyone's at it. Perhaps it's a sign of the times: a psycho­social response to the credit crunch, a reaction against the millennial excesses of the early noughties. But suddenly, it seems, clean-living role models are all around us.

For every pie-eyed party animal pictured leaving Chinawhite at 3am, there's a Chris Martin, a Natasha Kaplinsky, a Catherine Tate. Amy Winehouse may still be keeping the gossip columnists busy, but more and more of her partners in pop are sticking to the San Pellegrino and taking an early cab home. Little Britain's David Walliams, a noted man about town, never has anything other than mineral water in hand. Former Blue Peter presenter Konnie Huq may frequently be seen bouncing out of The Ivy, but in full control of her faculties. Note, too, the clear skin and bright eyes of the "alcohol intolerant" newsreader Kaplinsky, or Simon Amstell, presenter of TV quiz show Never Mind the Buzzcocks, who also eschew all poisons.

The list goes on. Tate hates the "loss of control" she experiences when drinking. Martin of Coldplay, his missus, Gwyneth Paltrow, and The X-Factor's massively successful songstress Leona Lewis are noted abstainers. And sobriety isn't just a celebrity-specific trend. Members of high society and politics alike are clean livers. Prince Andrew, French president Nicolas Sarkozy and even George W Bush have joined the club.

And then there are the sports stars. All-nighters aren't conducive to being on top of your game, which probably explains why tennis ace Andy Murray is teetotal. Boxer Ricky Hatton abstains for most of the year before a fight, letting down his guard only for a brief, post-fight celebration.

In Hollywood, actor Jared Leto recently describ­ed how he's more interested in putting on a good show with his band 30 Seconds to Mars than the more hedonistic side of rock. Sober nights out wouldn't be dull in LA, of course: Leto could social­ise with fellow abstainers Jim Carrey, Tobey Maguire, Natalie Portman, Bruce Willis and Samuel L Jackson.

All of which makes the antics of Rolling Stone Ronnie Wood especially striking. The 61-year-old's recent drunken sojourn in Ireland, accompanied by a 19-year-old Russian wait­ress, was as retro as it was rock 'n' roll. When actor Rhys Ifans drown­ed his sorrows after splitting from Sienna Miller, he attracted as much opprobrium for his drinking as sympathy for his emotional distress. Peaches Geldof, three sheets to the wind again? Oh dear.

So what's behind the new vogue for clean living? Jessica Callan, author and former Daily Mirror gossip columnist, insists there are no hard and fast rules as to why celebs are choosing to the clean life.

"Some choose it for weight reasons – to pursue various diets, such as a macrobiotic diet – others, Chris Martin for example... simply can't handle alcohol. I interviewed him once and he said the reason he didn't drink was that he was a total lightweight.

"But generally, celeb­rities are control freaks. They don't drink because they don't want to slip up. David Walliams has been tagged in various newspapers as something of a ladies' man, which makes him a target for a kiss-and-tell sting. And as he does serious acting as well as comedy, he doesn't just want to be known for his love life."

Alexandra Shulman, editor of Vogue, believes a reduction in people's consumption of drink and drugs is reflected in the popularity of the detox, essentially the recent trend for spa breaks. "So many more people are detox­ing now. Everyone I know seems to go off to a health retreat once a year, certainly over the past five years.

"What one forgets is that people don't really stop drinking in their 20s. When they reach their late 30s, however, people begin to think about the effect drinking and partying hard is having on them... There's more pressure on people nowadays to look great while still being able to party – and one way of doing this is by detoxing regularly."

The former Blur bassist and one-time legendary Soho party animal Alex James reckons the reason he curbed his notoriously excessive lifestyle was growing up and having children. The noughties, he says, are less of a "party" decade than the 90s.

"You can't be sloshing out the champagne in these credit-crunch days. Going on a good bender also needs a lot of time. You need to book a lot of space in the diary. Nowadays, people seem to want to get up and out in the mornings. I've gone from being a creature of the night to a daytime person. Of course, many of my friends also started having kids, which kind of disrupts the hedonism somewhat," he says.

"Adults make babies and babies make adults. Ronnie Wood is one of the best people to get pissed with, but he's a Rolling Stone. My boozing and shagging was cured by getting married. I changed as a person and my circumstances changed. Now I have something to come home to... It's getting old and boring that does it. It's brilliant in your 20s to be pissed and fabulous at 11 in the morning. But how old is Ronnie? He's about 82, isn't he? There just seems to be something a little bit wrong in that."

The reasons for abstaining from drinking are complex, according to Dr Rachel Sea­brook, research manager for the Institute of Alcohol Studies. "Drinking behaviour is complex and affected by many things, including cultural and economic factors. While the evidence that increasing numbers of people aren't drinking alcohol is very welcome, more research is needed into why."

One reason for the spread of sobriety is almost certainly the growth of alternative lifestyle philosophies. "New puritanism" resurrects Crom­wellian ideals of abstinence. Adherents shun the consumer society, binge drinking, junk food, smoking and cheap flights in favour of a more wholesome way of life.

The straight-edge movement is inspired by the 80s American punk band Minor Threat. Those involved avoid drink, drugs and promiscu-ous sex. Straight-edgers often draw a black cross on their hand, replicating the stamps given to under-21s attending gigs in the US.

Of course, for every back-handed cross, there is a drug- or alcohol-addicted rocker. Seabrook believes recent research indicates that while fewer people are drinking, those who are, are hitting the bottle to excess, thereby polarising society.

Martin Smith, director for the addiction treatment programme at The Priory rehab centre in London says: "I think there have always been people who chose to abstain for lifestyle reasons. But sadly, it hasn't had any impact on the number of people seeking treatment for addiction. If you're one of those people who can just take things or leave them, you are unlikely to ever knock on The Priory's door. Of course, just because someone can abstain for a brief period doesn't mean they don't have a problem with addiction. I don't think the number of celebrities having trouble with addiction has changed."

The number of celebrities sober after a spell in rehab are numer­ous. Kristin Davis, star of Sex and the City, is a recovering alcoholic, along with TV presenter Anne Robinson and artist Damien Hirst. Big Brother presenter Davina McCall and comedian Russell Brand have had well-publicised addiction problems in the past, but are clean now. The difference between those who resist the demon drink for lifestyle reasons and those who can't drink because they've had problems in the past is highlighted by Robinson, whose high-profile addiction to alcohol forced her to stop drinking in the late 1970s.

"On the one hand, in my experience, people are drinking less," she says. "The people I go out with of an evening quite often don't drink. Culturally, too, as a nation we don't drink like we used to... But for the Robbie Williamses of this world, those whom you may describe as a former addicts, that is a whole different story. I defy anyone to prove that figures are getting better for that."

Socialite Tara Palmer-Tomkinson suffered from high-profile drink and drugs problems in the past but is now clean and warns of the perils of partying too hard.

"I've not been to a nightclub in ages. Nowadays, I prefer dinner parties on my terrace or going out for a nice dinner. Of course, you do get people who go out and want to go crazy. I've never understood that mentality. Then again, I am a bit of a contol freak, perhaps it's the Capricorn in me. Drunk people really scare me.

"But I've noticed that increasing numbers of people don't drink alcohol any more – and drugs are completely out of fashion. They're now seen as a bit seedy and unglamorous."

TAKE A WALK ON THE MILD SIDE

The Irish stars embracing sobriety

Colin Farrell

Ironically, for a lad whose father owns a health food store, Farrell confessed in the past to downing – wait for it – 20 ecstasy tablets, four grams of cocaine, six of speed, half an ounce of hash, three bottles of Jack Daniels, 12 bottles of red wine, 60 pints [of beer] and 280 [cigarettes] a week. He entered rehab in 2005 for a prescription drug addiction and exhaustion, a process he described as "horrible". He's now clean and serene, inspired and motivated by his young son, James,

Jonathan Rhys Meyers

'The Tudors' star checked into rehab last year for alcohol problems, following what his rep called a gruelling filming schedule. He checked out two weeks later, possibly prematurely as he was arrested later on in the year in Dublin airport for being drunk and disorderly and breaching the peace. Three days later, following the death of his mother, he was seen drinking a can of Strongbow Super (that's 7.5% proof) at 9am, wandering the streets of London. Now back on the straight and narrow.

Roy Keane

For a substantial period of time, heaving drinking played a pivotal role in Keane's life. His sessions landed him in the newspapers on frequent occasions. In his autobiography, he writes: "The discovery that there was a serious drinking sub-culture at United was delightfully reassuring." In 1997, when a challenge made on Haaland, the Norwegian player, resulted in an injury that laid him up for months, Keane reached a turning point. He denies checking into the Priory or attending AA meetings saying he stopped drinking, sorted himself out and concentrated on the game.

John Leahy

Widely regarded as one of Tipperary's greatest hurlers, Leahy earned three All-Star medals. However his 20s were beset with alcoholic excess, which he subsequently overcame. He hung up his boots in 2003 and now speaks out about the dangers of alcohol in society. He now works as a drug education officer with Health Service Executive.