Sydney, Dec 18 (DPA) Santa Claus is a fat, heavy-drinking smoker who drives his sleigh dangerously and is into extreme sports like roof-surfing and chimney-jumping, warns an Australian public health specialist.

He is not a jolly fellow who spreads happiness but an agent of global capitalism with the potential to 'damage millions of lives' with his unabashed materialism and disregard for basic hygiene, Monash University epidemiologist Nathan Grills wrote in a paper published in the British Medical Journal.

Santa's 'rotund sedentary image' made 'obesity synonymous with cheerfulness and joviality,' the Melbourne academic argued Thursday.

'A recent study among hospital in-patients concluded that awareness of Santa was near universal,' he said. 'Given Santa's fame, he has considerable potential to influence individual and societal behaviour - and not necessarily for good.'

Santa, often depicted with a pipe, endorses smoking and his impersonators are vectors of disease through their serial cuddling of children, Grills added.

'Unsuspecting little Johnny gets to sit on Santa's lap, but as well as his presents, he gets H1N1 influenza,' Grills said.

By driving everywhere - and drinking at houses he visits - Santa is not only an irresponsible driver but an environmental vandal, his article warned.

'Despite the risks of high-speed travel, Santa is never depicted wearing a seatbelt or helmet,' Grills said.

According to the epidemiologist, Santa should 'adopt a more active method to deliver toys - swapping his reindeer for a bike or simply walking or jogging'.

He warned that Santa had always been a bad influence on impressionable young minds, recalling that in the 1930s, he was lending the Coca-Cola Co a hand by promoting its fizzy drinks - and that his fondness for tobacco and alcohol is legendary.

In blogs responding to Grill's paper, which the author admitted was partly 'tongue in cheek', Australians have mostly ganged up on the man in red.

Ha-ha said in a post: 'A man who drinks too much sherry, breaks into houses, gives the best gifts to the rich kids and uses a sweatshop of dwarfs for mass toy production? What better role model do children need?'

Coote said in a posting that having a fictitious concept as a Santa was a poor choice for a role model. 'I still give presents and talk about the joys of spending time together with family, just without the religious propaganda and Santa rubbish,' Coote said.