Legislation should be introduced forcing fast food outlets to use nutritional labelling on their products, if they fail to do so voluntarily, the Green Party says.
McDonald's has said it will include nutritional information on packaging of its burgers, fries and salads from next month.
Green MP Sue Kedgley said
other takeaway outlets should follow suit.
"Frankly it's bizarre that all takeaway outlets are exempt from nutrition labelling and unless they voluntarily follow McDonald's initiative, I believe this loop hole should be closed and mandatory labelling extended to all fast food," she said.
Ms Kedgley welcomed McDonald's packaging, but said nutrition labelling should include both saturated fats and trans fatty acids.
"Artificially produced trans fats have a direct impact on raising blood cholesterol and increase the risk of heart disease.
"It is essential that consumers can identify trans fats on nutrition labels and make informed decisions about whether or not to consume them," Ms Kedgley said.
"Two years ago McDonald's in New Zealand switched to oils low in both saturated fats and trans fats.
"If the level of trans fats in McDonald's food are low as a result of changing cooking oils, then McDonald's would benefit from letting the public know."
McDonald's marketing director Ian Sutcliffe said they had provided nutrition information for a number of years and would continue to find ways to improve the quality of their food.
"We are also evaluating additional cooking oil options to further improve the nutrition profile of our products," he said.
