The counter-intuitive link between poverty and obesity was established long ago, but a new study has found something even more startling - just feeling poor can make a person want to chow down.
The study of 500 people found that those who were made to feel poor ate around 20 per cent more in calories than other participants.
Nanyang Technological University (NTU) assistant professor Bobby Cheon, who headed the study, said the results show that the link between poverty and obesity goes deeper than what is usually thought.
"The study shows that we may not be able to address the issue by simply giving people more money or better food," said Prof Cheon, who is from the psychology division at NTU's School of Humanities and Social Sciences. "It's the feeling of being deprived, or having an inferior status compared to others, that is in itself a factor."
Prof Cheon got participants to compare themselves with the most privileged people in society so as to make them feel inferior. He then conducted four separate experiments to see their reaction to food.
All four experiments saw similar results - people who felt worse off tended to eat more or go for high-calorie foods, compared with both a control group and a group that was made to feel better off. He added that these changes in behaviour might become even more pronounced outside laboratory settings.
"If there are constant reminders that there are scarcity and deprivation, this could have a major impact over time," Prof Cheon said. "You don't actually need to be poor to be affected - simply feeling poorer or worse off than others is enough."
The study was jointly funded by NTU and the Singapore Institute for Clinical Sciences, and published in an international journal, Proceedings Of The National Academy Of Sciences, last December.
Eating behaviour expert Ciaran Forde, who is working with Prof Cheon on similar studies, said it is common for our beliefs and attitudes about foods to affect our eating behaviours. For example, he said, just our expectations of how filling a certain type of food is can affect the portion we choose, and even how full we feel after eating it.
Said psychiatrist Ken Ung, who works with patients with eating disorders: "I can see how the study makes sense - at the end of the day, a lot of eating is psychological and perception is everything."
The study had another interesting finding: While those who felt inferior ate more, those who were made to feel better off did not eat any less than people in the control group. In other words, feeling superior to everyone else is probably not going to shrink your appetite.
What could solve the problem, said Prof Cheon, is gratitude. After all, if feelings of inferiority stimulate appetite, feeling satisfied with life could very well reduce food intake, but this requires further study.
Of course, there are many factors affecting obesity, such as lifestyle or genetics. But more research in this field could pave the way to a better understanding of the topic, he said - not just counting calories, but also counting your blessings.
Correction note: An earlier version of this article referred to the Singapore Institute for Clinical Sciences as the Singapore Clinical Research Institute. We are sorry for the error.
