They are industrially-made fats, used to increase the shelf life of food.
But research has shown transfats can also increase your risk for heart disease and stroke.
A year ago, Health Canada introduced voluntary guidelines for limiting the trans-fat content in packaged and restaurant foods.
On Monday, the trans fat task force released its second report card. It indicates that for the most part, the program is working.
"What we are seeing here is a good example of industry taking responsibility and also meeting the demand of the marketplace. People are now demanding that their foods are healthier," said Steven Fletcher, pariamentary secretary to the minister of health.
Most fast food chains and restaurants have responded, limiting transfats to the recommended less than 5 per cent of the total fat content in foods.
"Many, many of our restaurants are doing a fantastic job and if you look at the data and see the progress that's been made across the board and across the country,'' said Ron Reaman, vice-president, Canadian Restaurant and Foodservices Association.
But the worst offenders were some margarine producers, and donut makers.
Dunkin-Donuts' chocolate glazed donut takes the cake. It's loaded with trans fats.
And many soft margarines still contain unnecessarily high levels of trans fat.
"If it ever comes down to the shelf life of a donut or the shelf like of a human being, I think we should err on the side of the human being," said Pat Martin of the Manitoba New Democratic Party.
And for the most part that's what's being done.
Even fast food chains like Burger King, who failed the task force's first report card, have improved and say they will meet the transfat requirements by the end of the year.
With a report by CTV British Columbia's Dr. Rhonda Low
