One of the authors of a study on obesity says the main reason the number of overweight New Zealanders is increasing is because of overeating, not a lack of exercise.
Elaine Rush from the Auckland University of Technology contributed to the international research on diet and obesity.
She says the study used data from 2,000 people, including New Zealanders.
Ms Rush says the statistics show New Zealanders are eating more kilojoules of energy than they can burn off in a day.
She says changes to diet and exercise need to go together when reducing weight.