A drive towards reducing obesity could have important consequences for the environment
and the long-term future of the planet, according to new study published by the International
Journal of Epidemiology.
Researchers from the London School of Hygiene & Tropical Medicine in the UK investigated the link between Body Mass Index levels by nation in order to estimate the impact of being overweight on the levels of greenhouse gases emitted by a given population.
Results revealed that, compared with countries showing normal BMI averages, a population with 40% obesity requires a huge 19% more food energy for its total energy expenditure. A country with a slim population and low overweight level such as Vietnam will produce nearly one fifth less greenhouse gas emissions than countries such as the US or the UK, according to the findings.
Consequently, the current research suggests a population of one billion with high obesity levels could produce as much as 1 extra gigatonne of carbon dioxide emissions every year, approximately one sixth of the level produced yearly by humanity according to the European Environment Agency. 
Co-researchers Phil Edwards and Ian Roberts from the Department of Epidemiology and Population Health at LSHTM have called on governments to help create policies more conducive to a healthy lifestyle that encourages sustainability and a reduction in obesity.
"Policymakers can promote this by making active transports like walking and cycling safer, as well as making healthy food options available at schools and workplaces", wrote Dr Edwards.
Being overweight should be recommended as an "environmental problem", said the researchers.
However, the co-authors warned that all countries would need to consider the issue due to the fact that obesity levels are currently rising in every country in the world, with the average adult nearly 3kg heavier than s/he was fifteen years ago.
"Staying slim is good for health and for the environment. We need to be doing a lot more to reverse the global trend towards fatness, and recognise it as a key factor in the battle to reduce emissions and slow climate change", Dr Edwards concluded. 
The current study follows on from similar research published in the Lancet in 2007 focusing on the impact of meat consumption for the environment. Australian scientists produced findings suggesting that many of aspects of the 'meat chain' significantly exacerbated climate change , conclusions echoed by Rajendra Pachauri, chairman of the UN Intergovernmental Panel on Climate Change and an individual considered by many to be the world's leading expert on climate change, who urged consumers to begin with one meat-free day each week. (7.24.2009, Michael Jolliffe, citizen journalist, See all articles by this author, Email this author)
 Edwards et al. Population adiposity and climate change. International Journal of Epidemiology. 2009; 1-5.
 McMichael et al. Food, livestock production, energy, climate change, and health. Lancet 2007 Oct;370(9594):1253-63. http://www.naturalnews.com/026690_climate_change_health_obesity.html