To take any food and claim that it is healthy using the logic that anything from nature is inherently healthy. The key identifiers are if an item came from the ground (plant, tree, etc) or if it came from a natural being (man, animal) such as milk, etc.
The effect is using Kevin Bacon 'Six Degrees' style of trackbacks to nature and stretching natural chemicals into an excuse for anything to be healthy.
Chocolate is healthy for you. Chocolate comes from cocoa beans which come from trees. It is often made with milk which comes from cows. Trees and cows are natural beings, therefore Chocolate is easy to healthify.
(v) The act of attaching an aspect of "health" to a food that would never be considered healthy.
They healthify chips these days because a lot of chips have no trans fat and 35% more fiber.