More than half of adults and one third of children will suffer from obesity by 2050

BarcelonaThe strategies of the last 30 years to contain the advance of obesity in the world have failed and, without strong political action, the projections for 2050 are not optimistic. This is the scenario drawn by the most exhaustive global analysis of overweight and obesity carried out to date, the The Lancet Global Burden of Disease Study. According to the study led by the University of Washington (UW), cases have doubled between 1990 and 2021, with more than 2.1 billion adults and nearly 500 million children and adolescents affected. That is, four out of ten people in the world are obese. But in 25 years, these figures are expected to increase further: 60% of those over 25 years of age (3.8 billion) and a third of children and young people between 5 and 24 years of age (746 million) will suffer from a disease due to excess weight.

"The unprecedented global epidemic of overweight and obesity is a profound tragedy and a monumental societal failure," says Emmanuela Gakidou, a doctor from the UW Institute for Health Metrics and Evaluation and lead author of the analysis. The report reveals that global rates of overweight and obesity among adults will increase from an estimated 43% in 2021 to 57.4% for men by 2050. For women, the figure will rise from 47% to 60%. "The estimates are realistic and not surprising, but they are extremely worrying. These are the disastrous figures that we will have to face in the future if we do nothing now," says Andreea Ciudin, coordinator of the Comprehensive Obesity Treatment Unit at Vall d'Hebron Hospital, who did not participate in the report.

The authors of the analysis stress that these results should be interpreted as a global warning: if urgent political action is not planned and implemented, there will be an unprecedented increase in obesity and premature diseases (such as diabetes, high blood pressure and some cancers). The largest number of overweight and obese adults in 2050 is expected in China (627 million), India (450 million) and the United States (214 million), partly due to their large populations. However, by region, the largest increase will occur in countries in Oceania and North Africa and the Middle East.

Although it will not be the most affected country in the world, the study –which has received funding from the Bill and Melinda Gates Foundation– suggests that Spain could be one of the high-income states with some of the most worrying figures. It is estimated that obesity will affect 23% of boys and 21% of girls aged 5 to 14; 23% of young women aged between 15 and 24; and 45% of women over 25.

The study takes into account the socioeconomic level of the countries and notes substantial differences by age and sex. In high-income countries, in the group of children (5 to 14 years) and as regards boys, the most affected countries will be Chile (37% of the population), Australia (27%) and Greece (26%), while as regards girls of this age group, the list will be led by Chile (2003) and 30 (30%).

Among adolescents (15 to 25 years), Chilean youth will again be the most affected by obesity (31%), followed by Americans (31%) and New Zealanders (28%), although in the case of young girls the prevalence will be higher among North Americans3). Countries do not vary much for adults: both men and women with the highest obesity rates will live in the United States (55% and 59%, respectively), Chile (53% and 56%) and Australia (49% and 55%).

The next generations

The authors point out that younger generations are gaining weight faster than previous generations. For example, in high-income countries, 7% of men born in the 1960s were obese at age 25, but for those born in the 1990s the percentage doubles (16%), and for those born in 2015, it is estimated that it will rise to 2%. "But if we act now, it is still possible to prevent a complete transition to global obesity for the youngest," says co-author and researcher at the Murdoch Children's Research Institute (Australia) Jessica Kerr.

Ciudin agrees, stressing that this analysis should be the "last warning sign" for all the policies and sectors involved - health, education and industry - to work together, although she believes that it will be "difficult" to reverse the obesity curve. "We are going to continue to increase obesity figures because there are many people with the disease and that influences the following generations. Today's disease influences babies yet to be born," explains the endocrinologist. The children of an obese woman are more predisposed to suffer from the disease due to epigenetic weight, just as an obese man has sperm with modified DNA prone to obesity, she exemplifies.

The researchers used the body mass index (BMI) to determine the prevalence of overweight and obesity in 204 countries from 1990 to 2021. However, Ciudin recalls that the criteria have evolved - now body fat, age and symptoms, symptoms, prompts and symptoms are taken into account.

The authors call for more coordinated efforts to offer comprehensive interventions tailored to the unique sociodemographic, economic, environmental and commercial situation of each territory. "But focusing only on diet and exercise is very simplistic, since in most cases this is not enough," says Ciudin, who argues that it is necessary to assess case by case whether the best treatment is pharmacological or surgical. "There are now drugs to reorder altered mechanisms that are excellent, but there are access problems and they do not work in all cases either," he argues. In fact, the study did not consider the potential impact of drugs such as Ozempic, which could alter the long-term prognosis of these diseases.