Around half of the world’s population – close to four billion people – could be living with overweight or obesity by 2035. The projection highlights the scale of a global health challenge that affects both adults and children and increases the risk of serious long-term diseases.
Marked every year on World Obesity Day, the awareness campaign focuses on understanding the causes of obesity and encouraging prevention, early support and equitable access to care.
Childhood obesity rising rapidly
One of the most concerning trends is the increase in childhood obesity. Rates among school-aged children have grown almost fivefold since 1975, with particularly rapid increases seen in low- and middle-income countries.
Childhood obesity often continues into adulthood. This increases the risk of developing non-communicable diseases such as type 2 diabetes, cardiovascular disease and certain cancers later in life.
Health experts note that early prevention and supportive environments are key to slowing this trend.
A global issue affecting billions
Current estimates suggest that almost three billion people worldwide, including more than 400 million school-aged children, are already living with overweight or obesity.
If present trends continue, that number could reach around four billion people by 2035.
Obesity therefore represents not only a health challenge but also a social and economic one, affecting healthcare systems, productivity and quality of life.
Obesity is shaped by social and environmental factors
Public health specialists emphasise that obesity does not occur in isolation. A wide range of factors influence risk across the life course.
These include:
- poverty and social inequality
- limited access to education and healthcare
- environments that make physical activity difficult
- the widespread availability of inexpensive, energy-dense foods
- stigma and discrimination related to body weight
Together, these factors can make healthy choices more difficult for many people.
Changing the trajectory
Experts stress that the current trends are not inevitable. Prevention efforts can begin early in life, while policies that support healthier environments can make a significant difference.
This includes improving access to nutritious food, creating communities that support physical activity, strengthening health education and ensuring that people living with obesity have access to appropriate medical care without stigma.
World Obesity Day 2026 calls for collective action across governments, healthcare systems, schools, communities and families.
