More than half of all South Africans are now classified as medically overweight or obese, and this has serious implications for the health system.

As urban centres continue to grow across Africa, South Africa vies for bragging rights as the continent's economic powerhouse. But in terms of the number of people who are overweight or obese, there is one clear winner: South Africa.

According to the most recent World Health Organisation data, more than half of adults in the country are overweight or obese: more than a 10% increase in the last 25 years. In South Africa, undernutrition remains a major challenge, with rates far exceeding those expected, given its economic status. The impact on health systems, not just in South Africa, but globally, is unsustainable.

The government has been a pioneer in adopting a countrywide soda tax and this is a step forward. But without a programme to educate the South African public on the effects of obesity or a comprehensive national study which lays down a marker on the magnitude of the problem, it will not be enough to turn the tide.

Although the economy turned a corner in 2002, it currently finds itself much closer to the...