We make food decisions several times a day – from what time we eat to how much – but a new joint study by the University of Newcastle and the University of Otago, New Zealand study has found we are not very good at judging the energy-density of what we consume.
Lead author Dr Mei Peng, of the Department of Food Science at the University of Otago, said inaccurate judgements about food energy and/or portion size can lead to overeating and subsequent weight problems.
The research, supported by the Marsden Fund and published in journal Appetite, was carried out in conjunction with Associate Professor Ami Eidels of the University of Newcastle, who alongside his students and colleagues at the Newcastle Cognition Lab, School of Psychology, study how people process multiple sources of information.
The technique of using mathematical and computational models to understand how people use information to make decisions, in the lab and in real life was, for this study, adapted to the context of food choices.
“It was both encouraging and gratifying to see how our theories and models can inform real-life problems,” said Associate Professor Eidels.
The group studied how 70 people made decisions between food energy and portion size and found people were good at assessing food quantities, but not the energy density of food.
“We were particularly surprised to see substantial variations across people for judging food calories,” said Dr Peng.
“Although people are generally good at differentiating high-calorie foods from low-calorie foods, this judgement process appears to be more intuitive for some than others. For some people, if a high-calorie food is presented in a small quantity, it appears to be less ‘unhealthy’.”
As many of the available health guidelines are based on portion sizes, the researchers believe people need to be better informed about food energy content.
Dr Peng believes more explicit and salient energy labels on food packages might be one of the possible methods to help people to make better decisions.