For the past few years, I have been following the recommendations of the DASH diet developers, which are similar to the USDA recommendations. But I am always interested in other food pyramids. A British dietician, Melanie Thomassian, in her Dietriffic blog, presented the British food pyramid, which turns out to be more of a pie. Considering the popularity of savory pies in the UK, this seems appropriate. The UKFSA food pie groups fruits and vegetables together. The USDA and DASH food pyramids separate them, because they have different nutrient profiles. The UKFSA pie groups the potato with grains, presumably because they are similarly starchy. The USDA groups the potato with vegetables because, well, it is a vegetable, and (starchiness aside) is nutritionally most similar to other vegetables.
By putting the potato with grains, the UK food pie recognizes the potato's role as a staple food. The last time I visited (several years ago now), the potato was a part of "meat and three veg", a standard choice for the evening meal, highly desirable in a breakfast "fry-up", and often eaten at noon. In vast territories of the US, however, the potato fell out of favor during the low-carb craze. Grains are coming back into fashion, but the potato, excellent source of calcium though it is, is presented by the USDA as one of a "vary your veggies" menu. And, because it is not featured in the "eat more dark greens, orange, and dry beans and peas" advice, it is now pretty low in the vegetable rotation. Somewhere down there with kohlrabi and tomatoes, I suppose. But I suspect the potato is more popular than the USDA is letting on. Many restaurants still offer a choice of "potato, pasta, or rice" with the main course. McDonald's still sells a lot of fries. And Waffle House still offers hundreds of variations on the hash brown.
When I was growing up, there were only four food groups in the US. A potato was equivalent to a grain. These days, though, I am much more likely to have a grain (pasta, rice, biscuits, or bread) than a potato with the evening meal. Occasionally, I'll serve a grain AND a potato. It feels a little strange to me, but I do it any way. The DASH diet advises choosing tomatoes and dark green leafy vegetables for half of the weekly vegetable servings, and choosing a variety for the other half. I could still work a potato in there fairly often. Especially if it is a cold potato, which has "better carbs".