Researchers at the London School of Hygiene and Tropical Medicine published a study showing that, because of food production and transportation factors, a population of heavier people contributes more harmful gases to the planet than a population of thin people.
Given that it takes more energy to move heavier people, transportation of heavier people requires more fuel, which creates more greenhouse gas emissions, the authors write.
The study offers this novel approach to the global warming problem as US lawmakers discuss the future of climate change legislation. This week, the House Energy and Commerce Committee is scheduled to begin on a comprehensive energy and climate bill. On Friday, the Environmental Protection Agency announced that six greenhouse gases pose potential health hazards, an announcement that could prompt the regulation of the gases.
More than 1 billion adults worldwide are overweight, and about 300 million are obese, the study said. Generally, the body mass index, a measure of obesity, is increasing in most countries worldwide, from China to European countries to the United States. 研究称，全球有超过十亿的成年人超重，其中大约有3亿人过度肥胖。总体而言，从中国到欧洲再到美国，世界大多数国家的体重指数（BMI——肥胖测量标准）一直在增长。
BMI is going up because of the availability of food and motorized transportation, Edwards said. People are less active now than they were 30 years ago, and the prence of fast food has given people less healthy, more energy-dense options.
"In terms of environmental impact, the lean population has a much smaller carbon footprint," Edwards said.
The population with 40 percent obese people requires 19 percent more food energy for its total energy expenditure than the population with 3.5 percent obese people, the study showed.
"The findings make sense and highlight an important global co-benefit of losing weight, along with the significant personal health benefits," said Patrick Kinney, associate professor at Columbia University's Mailman School of Public Health, who was not involved in the study.