Walnuts and ground flaxseeds have been two LC foods that have done the trick for me.

Plus, they're packed with healthy omega oils.

Another trick I use to keep fat intake up and satiate hunger is a tablespoon or two of olive oil followed by a glass or two of water, as well as keeping plenty of hard-boiled eggs in the fridge and eating them with the yolks as snacks, which is almost as good a protein as whey powder shakes and really economical and tasty.