Some things are just naturally healthy.
This is a dish I learned from my college roommates. It is like civche (sorry if I spelled that one wrong) but instead of shrimp it is imitation crab.
What you will need is:
1 or 2 tomatos
3 or 4 lemons
and 1/2 pound of imitation crab meat
Optional: salt, peper, ketchup, and your choice hot sauce
Just dice everything up and mix together, except the lemons which you juice and squeeze over the top.
I personally like it with a little salt and chalula.
It is a great fresh dish, that can be eaten on its own, or with chips, as a side, on a tostada.