Calgary is just hours away from becoming the first city in Canada to regulate trans fat, with new grease-fighting rules set to kick in on New Year's Day.

The new rules ban restaurants in the city from cooking with oils that have a trans fat content of two per cent or higher.

And margarines and spreads used in restaurants must also remain below the 2 per cent threshold.

The artery-clogging trans fats have become a top target of health advocates in recent years, but Calgary is the first Canadian municipality to set limits -- following the example of Chicago and New York.

The city has launched a two-phase plan, said Dr. Richard Musto, executive director of public health for the Calgary Health Region.

"Phase one requires the use of oils and spreads that contain less than two per cent trans fat," Musto told CTV's Canada AM.

"Phase two, which will be effective sometime in middle of January of the middle of 2009, requires that all processed or manufactured foods contain less than five per cent of their total fat content as trans fats."

Musto said officials from Calgary Health found that most restaurants within the city are already within compliance with the new standards, but the new rules will ensure everyone follows the rules.

"First of all, our survey of 400 of the operators conducted this past fall revealed that better than 80 per cent are already in compliance with the use of the oils, and two thirds with respect to the spreads. So most have already moved there, they know this is a trend in our society to expect safer, healthier foods," Musto said.

Inspectors will be visiting restaurants in the coming months to ensure they are within compliance, and will work with the facilities to ensure they can meet the requirements, Musto said.

Though the vegetable-based oils that meet the lower transfat content rules are often more expensive, Musto said the higher cost will be absorbed by the fact the healthier oils don't need to be changed as often.

According to the Heart and Stroke Foundation of Canada, the consumption of trans fats accounts for between 3,000 and 5,000 deaths every year in Canada alone.

Cargary's Chief Medical Officer Dr. Brent Friesen said the change will mean major health benefits for residents.

"With healthier choices we can see a reduction of somewhere between six and 22 per cent in cardiovascular disease," he said.

Trans fat occurs naturally in low levels in some animal-based foods. However, it is also generated when liquid oils are turned into semi-solid fats such as margarine.

Trans fat has been linked to obesity, clogged arteries and high cholesterol.

Restaurants in Calgary will be given a five month grace period to institute the changes before risking health code violations and having their operating permits pulled.