A new perspective on global population is the subject of research published this week by the open access journal BMC Public Health.The report identifies global human population not by number, but as in the case of marine and land animals, by biomass. The result is a world that has not 7 billion humans, but 287 million tonnes of humans.
The method is a new approach to planning global sustainability. As one of the paper's authors, Professor Prof Ian Roberts from the Lomndon School of Hygiene and Tropical Medicine says, "Everyone accepts that population growth threatens global environmental sustainability – our study shows that population fatness is also a major threat. Unless we tackle both population and fatness - our chances are slim."
Of the 287 million tonnes of people on the Earth, 15 million tonnes is due to people being overweight, and 3.5 million tonnes is the contribution of obesity. The paper used data swupplied by the United Nations and World Health Organisation (WHO), with the average human body mass at 62kg.
However there are significant distortions in the data, with the average body mass in North America at 80.7kg, 30% higher than the global average. The paper reveals that North America has 34% of total human biomass, but on 6% of the world population. By comparison, Asia's 61% of the population provides only 13% of total human biomass.
New Zealand is the 29th highest in terms of biomass, but we are not as fat as Aussies.
Ref: Sarah C Walpole, David Prieto-Merino, Phil Edwards, John Cleland, Gretchen Stevens and Ian Roberts, The weight of nations: an estimation of adult human biomass BMC Public Health (in press).