Tanzania, April 22 -- Cities are growing faster in sub-Saharan Africa than elsewhere, with an annual urban population growth rate of around 4 percent compared to the world average of 1.5 percent.

Across the continent the urban share of the total population is projected to increase to 50 percent by 2030 and 60 percent by 2050.

Urbanisation is associated with lifestyle changes such as less physical activity and less labour-intensive work.

This is often accompanied by an increased intake of high-calorie fast foods, snacks, and sugar-sweetened beverages.

This combination has contributed to rising obesity in cities in low- and middle-income countries.

At the same time, undernourishment and micronutrient deficiencies remain a problem.

In ...