I see bunch of foods advertise "Grain Free" but then you look at it and it just has a bunch of potatoes, or lentils, or some other starch filler. There isn't any less "non-meat" filler, or even any less protein content, rather they just swapped out the grains for some other cheap carbohydrate filler. I was thinking about this, potatoes and lentils aren't inherently healthier than grains. A lot of grains could be more nutritious. Potatoes are pretty low on the nutrition density. It really doesn't seem an upgrade if "Grain Free" means they swapped out some grain for potatoes.

I'm just wondering, where did this come from? Is there any good reason for it? Or did "Grain-Free" just become like a buzzword?

So both vets in my family and the 2 that see my dogs and splinters cardiologist all recommend grain inclusive food. Something to do with peas and lentils changing the protein and that dogs actually cant digest peas and it causes other things not to be digested or absorbed correctly like taurine. So my boys are on grain inclusive and the girls are on raw. But really most of it is speculation that grain free dog food can cause dcm. So if your pup will tolerate grain inclusive, go that way or look for a food that avoids peas and legumes. But years ago it was a craze, and i wonder how much the blue Buffalo commercials had to do with it.

To an extent for some breeds it's a craze. There are definitely some dogs who don't tolerate certain grains, but there are also dogs who don't tolerate potatoes. For the most part high carb food is high carb food. Neither if the carb ratio is too high are particularly healthy for our animals. Grains and potatoes are substitutes for each other to add carbs, while lentils offset meat content to bump protein ratios. They are two separate items of 'nutrition' to think about when selecting a dog food. I personally have not seen a quality study that suggests one is 'healthier' than the other. It's more about what your individual can tolerate. My personal feelings are that dogs, like humans, do not thrive on a fully processed diet, so regardless of what kibble a person might feed adding in quality unprocessed foods is important when possible for truly balanced diet. Mine get a mix of a couple different kibbles, The Honest Kitchen, and raw foods. We generally do grain-free but I can get away with rice. Barley and wheat tend to ramp one of my males yeast production into overdrive and his skin starts to stink. Potatoes give my female ear infections so we don't do those either.