Otago University obesity researchers have identified a list of 49 foods they say contain lots of energy but are essentially bereft of nutritional benefits.

While the list contains the usual suspects of fatty foods and soft drinks, it also throws up some surprises, such as fruit juice, honey, and even muesli bars which can be more fattening than toffee pops.

The NEEDNT, or non-essential, energy dense, nutritionally deficient, list was published in the New Zealand Medical Journal on Friday, and has been developed primarily to help obese people better identify those foods best avoided.

Lead author Jane Elmslie stressed it was not just another list of high calorie foods, but also showed those low in essential nutrients such as vitamins and minerals.

The list names the generic food, and suggests a healthier replacement, or none at all for foods such as ice cream, cakes, chocolate, doughnuts, jam, pies and pastries.

"Muesli bars are a classic example of how overweight people can be misled into thinking they're eating healthy food," Dr Elmslie said.

"Most muesli bars are high in calories, and fat and sugar, with minimal nutritional value. Essentially they are just another form of biscuit."

She said people were bombarded with food advertising, and many foods that people believed were healthy were described in glowing terms on the label, but it was hoped the list would help them make better choices about what they ate while trying to lose weight.