Fish contain good amount of protein which is an essential part of daily diet. If you have any problem in eating fish, you can go for meat or chicken as these two also contain good amount of protein. Problem with latter two is that these foods also contain high amount of fat as compared to fish. Varieties of fish like sardines and mackerel contain acid called OMEGA 3 fatty acid which is very beneficial in ailments of heart diseases and arthritis.
If you are a veggie then can have dairy products and soy beans in your diet