My mother has always considered them veggies (or vegetables - she hates the term "veggies"). My mom also considers a salad a complete vegetable. Technically, I suppose she is right, but I'm now more of the mindset of having salad AND a veggie.
I have heard corn referred to as a grain. I do know it is hard to digest and I have seen (TMI time) whole kernels in the feces of people for whom I have to do total care. I'm not at all sure if humans were built to eat corn as a vegetable.
As someone else mentioned, potatoes in and of themselves are not bad (and neither is popcorn, in my humble opinion), it's what we put on them that makes them loaded with calories.
There are different philosophies of eating. Some say you must count total calories and that all calories are equal. Others say to stay away from preservatives and processed foods and eat only whole foods. The whole foods philosophy often admonishes about eating white foods, such as white sugar, white bread, AND white potatoes. I really don't know how white potatoes get onto the list, because they are not refined foods. I prefer red potatoes to white anyway, so I suppose there are no worries.
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