Consume Product

You seem to have misunderstood. Sure you could say that the body doesn't "recognize calories" but neither does it recognize the number of zeros in your bank account. It's still a quantifiable and useful way to look at food. In general, if you consume more calories than your body uses, you'll gain weight. I say "in general" because yes, there are foods that have caloric values that our bodies can't access, there are foods that cost a lot of energy to digest which negates their caloric values, and there are foods that contain or break down into compounds that promote fat storage regardless of the metabolic state of the body. That doesn't change the fact that you need to have consumed an excess amount of useable calories for fat storage to happen, in other words, if you eat too much, in general, you gain weight. Carbohydrates are not "poison" and you can certainly become overweight without them.