A new study tried to evaluate the impact of humans on the environment by calculating the total mass of the population, instead of actually counting heads. Their findings conclude that humanity weigh in at some 5400 Titanics or 287 million tonnes.
“When people talk about sustainability, they quickly get into concerns about population,” says Ian Roberts of the London School of Hygiene & Tropical Medicine in the UK.
The sheer number of human individuals, however, fails to measure properly the real impact of our race. By evaluating weight, scientists hope to provide data that is easy to read and more adaptable to modeling extra factors, like over-consumption. ”This is a statistic that measures both,” Roberts says.
For their study, the researchers employed data from a 2005 census, which also had information regarding body mass index (BMI) and average height. Body mass index is defined as the individual’s body mass divided by the square of his or her height, and serves as a reliable indicator. If you’d like to know if you’re underweight, normal, overweight or obese, check this graph (in pounds).
By factoring in population data, distributed over each country, the researchers concluded that the total adult population of the world weighed 287 million tonnes; the true figure, however, is much larger as it doesn’t include children. Of the total world population mass, 15 million were attributed to individuals who were overweight. Speaking of which, of the global biomass attributed to obesity, 34 per cent is found in North America, and if all countries had the same BMI as the US, the added biomass would be equivalent to an extra 473 million adults of average mass.
The findings were published in the journal BMC Public Health.
source: New Scientists