18/06/2012 10:53 BST | Updated 18/06/2012 13:35 BST

Overweight People Put Unsustainable Pressure On Planet's Resources (And Their Excess Weight Would ‘Fill A Lake')

A new study shows that the increase in the average weight of populations is helping to put unsustainable pressure on the world’s natural resources.

According to new research published in BioMed Central’s open access journal BMC Public Health, the adult human population weighs in at 287 million tonnes - 18.5 million of which comes from overweight and obese individuals.

"This isn't a personal attack on fatness. In our study we're demonstrating this is a political problem," says Professor Ian Roberts who led the research at London School of Hygiene and Tropical Medicine (LSHTM).

fat people

"I feel sorry for people in rich countries, where in order to maintain a health body mass index, you’ve almost got to starve yourself, because the environment encourages fatness."

Roberts argues that rather than focusing on obesity, we should turn our attention to rising levels of 'fatness'.

"Thin people are getting fatter. If you're the thinest person in the office now, you'll still be fatter than the thinnest person would have been 10 years ago."

"You've got to live simply so others can simply live," he adds. "We’re on a small planet and are eating our own life support system."

The primary threat to food security remains the consumption of resource-intensive food by wealthy nations, such as meat, Roberts confirms. But he maintains that tackling population weight is also crucial for food security and ecological sustainability.

As the study’s authors pointed out at the Cheltenham Science Festival, if the whole world slimmed down through liposuction our excess fat would fill a lake the size of Derwent’s Water, reports The Times.

steak dinner

According to Professor John Mathers, director of the Human Nutrition Research Centre at Newcastle University body mass is the first indicator of how much food a person will consume.

“The bottom line is that increasing obesity does have major consequences for demand for food and therefore impacts on food security.”

“Because heavier people need more energy to fuel their larger body mass they consume more food than the equivalent lean person. Some fatter people may consume more energy-dense foods, such as foods that are rich in fat and/or sugar and low in water, but this is secondary to their consumption of more food."

Mathers suggests countries can mitigate the danger by preventing obesity, while reducing food waste and the consumption of animal-derived foods.

According to the study, the average body mass globally is 62kg.

In their league table of body mass, North America has the highest of any continent, with an average of 80.7kg.

While North America has only 6% of the world’s population, it has 34% of the world’s biomass mass due to obesity. In contrast Asia has 61% of the world’s population but only 13% of the world’s biomass due to obesity.

Despite our relatively small population, the UK came in 18th in the chart, taking up 1.3 kg of the world's biomass. Our average adult body mass is 167lb 2oz (75.8kg) and the British adult population is 30lb 7oz (13.8kg) fatter than the rest of the world.

Overweight People Put Unsustainable Pressure On Planet's Resources (And Their Excess Weight Would ‘Fill...

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