Obesity researchers have discovered we burn the same calories on physical activities as we have done over the last 20 years.
They found that there has been no reduction in the energy we expend on day to day activities, suggesting increased food intake may be the more important factor in obesity.
They found that there has been no reduction in the energy we expend on day to day activities, suggesting increased food intake may be the more important factor in obesity.
Professor John Speakman, from the University of Aberdeen, co-authored a paper from the research, which is published online in the International Journal of Obesity. He said: "We found that people have not reduced their energy expenditure over the same period that obesity rates have increased enormously.
"It seems that we have been misled by the anecdotal information about levels of our physical activity. When actual measurements of energy expenditure are analysed there is no evidence for a reduction over time."
Professor Klaas Westerterp, from the University of Maastricht, was the co-author. He added: "Because we found no evidence for declines in energy expenditure over the last two decades, this work suggests that the obesity epidemic has been largely driven by increases in food intake."
The researchers made their findings based on data gathered in studies from Europe, North America and the developing world using a sophisticated isotope based technique called the doubly-labelled water method which permits direct measures of an individuals energy demands as they go about their daily business.
The study is the largest collection of data using this method and the results that are revealed provide a striking contrast to popular conceptions about what has caused the obesity epidemic.
Link to the publication: Westerterp KR, Speakman JR. Physical activity energy expenditure has not declined since the 1980s and matches energy expenditures of wild mammals. Int J Obes 2008;27 May
"It seems that we have been misled by the anecdotal information about levels of our physical activity. When actual measurements of energy expenditure are analysed there is no evidence for a reduction over time."
Professor Klaas Westerterp, from the University of Maastricht, was the co-author. He added: "Because we found no evidence for declines in energy expenditure over the last two decades, this work suggests that the obesity epidemic has been largely driven by increases in food intake."
The researchers made their findings based on data gathered in studies from Europe, North America and the developing world using a sophisticated isotope based technique called the doubly-labelled water method which permits direct measures of an individuals energy demands as they go about their daily business.
The study is the largest collection of data using this method and the results that are revealed provide a striking contrast to popular conceptions about what has caused the obesity epidemic.
Link to the publication: Westerterp KR, Speakman JR. Physical activity energy expenditure has not declined since the 1980s and matches energy expenditures of wild mammals. Int J Obes 2008;27 May