Humanity weighs more than 5400 Titanics.
Of those 287 million tons, 15 million were the result of people being overweight. North America is the most overweight continent (surprise, surprise), with 6% of the global population but 7.4% of the human biomass. Of the global biomass attributed to obesity, 34% 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.
[Excerpted from New Scientist]