What counts as ultra-processed food? It's too complicated

There is no real evidence that a pizza made at home is better than a frozen store-bought one with the same ingredients.

- F. D. Flam

Ultra-processed foods, or UPFs for short, are suddenly the hot health concept—the new antihero in global diets. The topic is exploding both in scientific literature and on social media. There's even an artificial intelligence (AI) system to help consumers select less-processed foods while shopping.

But once you get past the important and obvious idea that junk food is harmful, the concept of ultra-processed becomes hazy and confusing.

There's unprocessed, processed, culinary ingredients and ultra-processed. So, what's the consumer supposed to do?

Nova, the most widely used system for categorizing food as ultra-processed, includes everything from doughnuts to frozen dinners. The unprocessed category includes fresh vegetables; culinary ingredients include things such as sugar, cooking oil and flour. Then there are the merely processed items, which include things like canned chickpeas, pasteurized milk and plain yogurt.

Under this system, a frozen dinner made with healthy ingredients such as fish and broccoli might fall into the ultra-processed category, but not a homemade cake with lots of sugar. There's no real evidence that a pizza made at home is better than a frozen store-bought one with the same ingredients.

And if it's the ingredients that matter, wouldn't consumers be better off with a science-based guide to which ingredients are harmful?

The ultra-processed classification system comes from Brazil, where Nestle, sensing the market potential, flooded the country with packaged food.

What followed was a corresponding increase in obesity and diabetes, although food industry executives justified the action by pointing out that the move decreased hunger.

Telling people to avoid ultra-processed foods is a big improvement compared with simply advising them to avoid high-fat foods and eat low-fat versions of things like yogurt, ice cream, energy bars and cereal—which are usually high in sugar.