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Obesity is today one of the greatest global public health challenges.

According to the WHO, in 2022 more than 1 billion people were living with obesity (650 million adults, 340 million adolescents, and 39 million children). By 2035, it is estimated that more than half of the world’s population will be overweight or obese. The fastest growth is occurring in low- and middle-income countries, where urbanization, sedentary lifestyles, and the availability of ultra-processed foods are replacing traditional dietary patterns. Obesity also overlaps with nutritional deficiencies in many regions, creating the so-called double burden of malnutrition.

Health impact

Excess weight is a central risk factor for multiple diseases. Metabolically, it accounts for more than 80–90% of type 2 diabetes cases. Cardiovascularly, it increases the likelihood of hypertension, coronary heart disease, heart failure, and stroke. Obesity is also linked to at least 13 types of cancer (colon, postmenopausal breast, endometrial, liver, among others). Other consequences include sleep apnea, osteoarthritis, infertility, chronic kidney disease, and non-alcoholic fatty liver disease. The impact also extends to mental health: depression, anxiety, and the burden of social and medical stigma, which affect quality of life and adherence to treatment.

Economic impact

The direct and indirect costs of obesity are enormous. It is estimated to consume between 2% and 7% of global healthcare expenditure, depending on the country. In the United States, direct medical costs exceed 170 billion dollars annually. Added to this are indirect costs: reduced productivity, absenteeism, disability, and early retirement. In middle-income countries, where obesity is rising fastest, the economic impact threatens the sustainability of fragile health systems with limited resources.

Social and geopolitical dimension

Obesity reflects and amplifies social inequities. It disproportionately affects communities with fewer resources, where healthy foods are expensive or inaccessible, and environments do not support physical activity. The ultra-processed food and sugary drink industries play a decisive role in driving the epidemic, particularly among children and adolescents. In response, several governments have implemented policies: taxes on sugary drinks, front-of-pack labeling, restrictions on advertising to minors, and food reformulation programs. However, market pressures and regulatory differences mean that the global response remains fragmented.

Near future

If decisive action is not taken, it is projected that by 2060 obesity will become the leading preventable risk factor for disability-adjusted life years (DALYs) lost, surpassing smoking. New obesity drugs (such as GLP-1 agonists and their combinations) hold promise for reducing the incidence of diabetes and cardiovascular events, especially in high-risk groups, but they do not replace the need for population-level prevention. The challenge lies in balancing pharmaceutical innovation, cost sustainability, and structural policies that make healthy choices easier and more affordable. Only a combined strategy —prevention, equitable access to treatment, and regulation of the food environment— can reverse the current trend.