Carlos Monteiro, a professor at the University of São Paulo, believes that "the big issue is ultra-processing."
That is to say, the most important factor when considering food and nutrition is neither nutrients nor foods -- it's what is done to foodstuffs and the nutrients contained in them before they are purchased and consumed.
Monteiro makes it clear that most foods and drinks are currently processed to some extent -- even fresh apples are washed and sometimes waxed, and drinking water is filtered.
But ultra-processed foods are all too common, and they are depleted of nutrients and provide little beyond calories.
According to the Atlantic:
"The purpose of ... ultra-processing is to create: durable, accessible, convenient, attractive, ready-to-eat or ready-to-heat products ... Monteiro argues: 'the rapid rise in consumption of ultra-processed food and drink products, especially since the 1980s, is the main dietary cause of the concurrent rapid rise in obesity and related diseases throughout the world.'"