Obesity without purpose, as it's usually seen in other species for reservoir and temperature conditioning, appears in the human species. From this perspective, other time, the procedure seems more rational in those species than ours.
Furthermore, obesity stands as an increased risk of experiencing multiple health inconveniences. A long list of issues that creates serious events, even fatal ones. In terms of quality of life, any excessive quantity of grease diminishes it as impedes movement, adds extra weight, more sweat and interrelated factors, and forces an extra effort for doing everyday tasks. The feeling, very different in comparison.
In a world where the resource distribution surpasses limits of injustice, with places lacking resources for nutrition, the act of having extra grease could be psychologically unpleasant, for the person and for others because from a reasonable perspective, it's not respectful. The act of wasting in front of the necessity.
After this introductory set of realities, it's time for the numbers. First, anyone should remember that obesity is a open concept, ready for subjective appreciations. Obesity in a 10% margin of the ideal weight differs from the threshold set at 40%. However, these are estimations taken from different sources that, surprisingly, don't specify the preferred definition.
In USA, the Journal of American Medicine says 34.9% of the adults in the country. This source also mentions: "[...] higher incomes are more likely to have obesity than those with low income." Then, high income types are more prone to assume health problems and less quality of life discontrolling the intake. It doesn't occur only in USA, but in the entire set of societies with high income per capita.
In Europe, the OMS says in 15 years, the percentage of people with more weight than normal could reach 7 of 10 men, and 6 of 10 women.
The global predictions establish worrying increases. Nevertheless you would trust a better education and awareness for a healthier life, specially in new generations.