>...people in Brazil were buying less sugar and oil than in the past. Yet rates of obesity and metabolic diseases were still rising. This coincided with the growing popularity of packaged snacks and ready-made meals, which were loaded with sugar, fats and other additives.

What. So they were buying less sugar and fat. But they were actually buying more sugar and fat?

They were buying less sugar and oil as ingredients to cook at home with. They were substituting home cooking by buying more ready-made foods and snacks that contained fat and sugar as components.