This nutrition scientist is on a mission to make ultra-processed foods healthier. Can he succeed?

• A landmark study suggested we eat about 500 extra calories per day on ultra-processed diets.
• Scientists are working to disentangle why this happens.
• They're developing new recipes for ultra-processed foods they hope will be healthier.

It's been five years since nutrition scientist Kevin Hall made a startling discovery that changed the way we view ultra-processed foods.