Approximately half South Africans across three major cities have an unhealthy weight, according to Discovery Health's latest "obecity" index.
According to BusinessDay on Thursday, only 53.5% of Capetonians had a healthy weight, a result marginally better than Johannesburg at 52%.
The figures from Port Elizabeth, however, show it is worst in the Eastern Cape city. Only 48.8% of residents -- less than half -- had a healthy weight.
The assessment was based on body mass index (BMI) and waist circumference.
Vitality head Craig Nossel reportedly said this points to the worrying extent of obesity in the middle classes, despite the options available to them.
Overweight or obese people have an increase in healthcare costs of about R4,400 a year, the study revealed.
According to Business Report, the index looked at the food-buying behaviour of around 500,000 Vitality members in Johannesburg, Pretoria, Cape Town, Durban, Port Elizabeth and Bloemfontein. Sales for ready-made meals reportedly grew by 40% between 2005 and 2010.
In June, the South African Demographic and Health Survey revealed that 13% of children are overweight in South Africa, Health24 reported. Almost 70% of all local women are either overweight or obese –- the highest rates for women in Africa.
Correction: An earlier version of this article incorrectly listed Cape Town as the worst ranking in the index.