Obesity, a condition characterized by excessive fat accumulation that impairs health, is a global health challenge that has seen a dramatic increase in prevalence over the past few decades. The World Health Organization (WHO) classifies adults with a Body Mass Index (BMI) of 25 or more as overweight and 30 or more as obese. The BMI classifications for children differ, considering their age in the assessment.
The global landscape of obesity reveals significant regional variations. In 2016, the average BMI for both men and women globally was around 25, the threshold for being overweight. Higher averages were observed in North and South America, and North Africa, while lower averages were noted in Sub-Saharan Africa and Asia. In some countries, obesity rates are alarmingly high. For instance, countries like Palau, Micronesia, and Mexico report obesity rates of 38%, 37.1%, and 36.9%, respectively. Conversely, regions like South Asia and Sub-Saharan Africa have lower prevalence, with around one in five adults being overweight or obese.
Childhood obesity is a particular concern, as children who are overweight or obese are likely to continue being so into adulthood. Obesity in childhood is linked to numerous health complications and a heightened risk of early onset of diseases. The assessment of childhood obesity also relies on BMI but uses different criteria compared to adults, based on the WHO Growth Standards.
The increasing rates of obesity are driven by a complex interplay of factors. Primarily, it is the result of an energy surplus – consuming more calories than the body expends. Over the past century, and particularly in the last 50 years, there has been a significant increase in calorie availability globally. In the 1960s, the global average supply of calories was around 2,200 kcal per person per day, which increased to 2,800 kcal by 2013. This increase in energy consumption, combined with a decrease in physical activity due to changes in work nature, increased use of transportation, and urbanization, has contributed to the rise in obesity.
The World Obesity Federation’s World Obesity Atlas 2022 predicts that by 2030, one billion people will be living with obesity, including 1 in 5 women and 1 in 7 men. This projection indicates not only a failure to meet the WHO’s 2025 target to halt the rise in obesity at 2010 levels but also a doubling of the number of people with obesity since then. The increase is more pronounced in low- and middle-income countries, with numbers more than doubling across all such countries and tripling in low-income countries. The Atlas also introduces an Obesity-Non Communicable Disease (NCD) Preparedness Index, revealing that the 30 most prepared countries are all high-income, whereas the 30 least prepared are lower middle and low-income countries.
Obesity is a major risk factor for chronic diseases like cardiovascular diseases, diabetes, and certain cancers. The rise in obesity has been paralleled by an increase in these non-communicable diseases. For instance, rates of diabetes have quadrupled globally since 1980. Obesity also contributes to musculoskeletal disorders, such as osteoarthritis, and is associated with an increased risk of various cancers.
Effective prevention and control of obesity require a multi-faceted approach. Reducing calorie intake from fats and sugars, increasing consumption of fruits, vegetables, legumes, whole grains, and nuts, and engaging in regular physical activity are key strategies. For children, exclusive breastfeeding from birth to 6 months has been shown to reduce the risk of becoming overweight or obese. However, no country has yet successfully reversed the trend of this growing epidemic.
The global increase in obesity, particularly in low- and middle-income countries, highlights the need for global action. It’s imperative for governments worldwide to collaborate with organizations like WHO to develop a comprehensive Global Action Plan on Obesity. This plan should address the multifaceted nature of obesity, including dietary habits, physical activity, and broader socio-economic factors.
The analysis of world obesity statistics underscores the urgency of addressing this growing health crisis. It calls for a concerted global effort to implement effective policies and interventions that can curb this trend and improve public health outcomes worldwide.
References:
- Our World in Data: Obesity Overview – Our World in Data
- World Population Review: Obesity Rates by Country 2024 – World Population Review
- World Obesity Federation Homepage – World Obesity Federation
- WHO: Obesity and Overweight – World Health Organization
- World Population Review: Most Obese Countries 2024 – World Population Review
- World Obesity Atlas 2022 – World Obesity Federation
- OECD Indicators: Health at a Glance 2023
