in general, it is not a good idea to mix refined carbs with fats. so it is permissible to eat carbs within limits but NEVER mix fat with them as the combo [especially when cooked] creates these acronymic things called AGEs [Advanced Glycation End-products] which contribute to systemic inflammation and premature aging. if you are going to have fat in your diet, #1 avoid trans-fats/hydrogenated anything, and #2 combine it with proteins, as in nature fats and proteins tend to be linked. healthy fats also aid digestion/nutritional assimilation of certain vitamins when accompanying some veggies [NOT potatoes]. also, as a general rule, "desert dessert" IOW don't combine sugary things with anything else at mealtimes, which is an extension of the recommendation against mixing carbs with anything else. separate sets of digestive enzymes [for carbs] will mix with those in charge of breaking down proteins/fats which in worst cases leads to incomplete digestion, with some things putrefying in the gut undigested which in the short term leads to stinky elimination/farting, and over a long time can lead to nasty things like the big C.