Study in China finds healthy thin people eat and exercise less rather than burning off excess calories
- Research team says its data overturns the common perception that underweight people burn off extra calories with physical activity
- The scientists monitored 323 Beijing residents for two weeks to learn more about why some people do not gain weight
Researchers say they have debunked the urban myth that healthy underweight people “eat whatever they want and burn it off with exercise”.
A study of healthy Chinese adults considered underweight, according to the widely used Body Mass Index (BMI), found they not only do not eat as much food as people with a “normal” BMI, they are also less physically active.
“Our data suggests they eat about 12 per cent less than adults with a normal BMI,” the team of scientists wrote in an article published by the peer-reviewed journal Cell Metabolism on Thursday.
“We can reject the hypothesis that healthy underweight adults derive their leanness from high levels of physical activity.”
The team, drawn from institutes including the Chinese Academy of Sciences, Beijing Technology and Business University and the University of Aberdeen in Britain, said the study’s “healthy underweight” participants were 23 per cent less active than the group with a normal BMI.
They also had higher-than-expected resting metabolic rates with an elevated resting energy expenditure and thyroid activity, the scientists said.
