The study found higher intake of several preservatives, which are often used to extend a product's shelf-life, were linked to higher risk of cancers.

Dr. Fang Fang Zhang, a cancer epidemiologist focused on nutrition, told USA TODAY the message to eat more whole or minimally processed foods is a good one, but whether Americans will really ditch soda and packaged snacks, "we have to see."

As the Trump administration looks to create a federal definition of ultra-processed foods, the question of the best way to differentiate products within a category that can lump packaged whole-wheat bread together with soda and cheese puffs has been the subject of much debate.

The new dietary guidelines call for prioritizing high-quality protein, healthy fats, fruits, vegetables and whole grains. Foods to avoid or limit are highly processed foods, refined carbohydrates and added sugars. The "food pyramid" has literally been turned upside down.

The new food pyramid, however, places vegetables, proteins, dairy and healthy fats like olive oil at the top, suggesting they should hold equal importance. Fruits and nuts are slightly lower on the pyramid, and whole grains are at the very bottom.

The guidelines also promote red meat and lower consumption of grains, while warning against added sugars and artificial sweeteners.

In the first lawsuit of its kind, the city of San Francisco is suing 11 of the nation’s top food companies, saying they sell ultra-processed food knowing they are harmful to health. By some estimates,

Norwegians eat more processed meat such as sausages and salami than in the other Nordic countries. For the first time, researchers have calculated the disease burden and years of life lost caused by an unhealthy diet.