Background:
Globally, the rising trend in mean body mass index has resulted in a substantial increase of the burden of non-communicable disease attributable to high BMI. Kenya has adopted the WHO target of halting the rise of overweight, including obesity, by 2025. This paper assesses the potential impact of achieving the set target on health, healthcare cost, and productivity.

Methods:
We used a proportional multistate life table model to quantify health outcomes, healthcare costs and productivity. We modelled the 2019 population of Kenya over their lifetime, comparing a scenario in which BMI distributions stabilise in 2025, against one in which BMI distributions stabilise in 2044. We identified estimates of the total health expenditure and disease specific healthcare costs in Kenya from literature. We used the Human Capital Approach to estimate productivity gains.

Results:
Halting the rise of overweight in the year 2025 is estimated to save 6.8 million HALYs (95% uncertainty interval [UI] 5.8- 7.9 million) over the lifetime of the 2019 Kenyan population (135 HALYs per 1,000 persons). Up to the year 2044, the leading contributors of the health gains were musculoskeletal diseases (537,052 new cases avoided; 95% UI 444,361- 639,460), followed by T2DM (466,030; 95% UI 360,103- 597,378) and cardiovascular diseases (301,729; 95% UI 248,559- 367,949). A total of US$ 755 million in body mass-related healthcare costs could be saved by 2044 (US$ 15 per capita) translating to 16% of Kenya’s annual healthcare expenditure or 1% of gross domestic product. Over the lifetime, over US$ 3 billion healthcare costs could be saved. In 2044, the total productivity gains resulting from a reduction in obesity-related mortality and morbidity (combined) could be as high as ~US$ 5.8 billion.

Conclusion:
Halting the rise of overweight and obesity not only improves health outcomes but also yields healthcare cost savings and productivity gains.