Are these fish oil supplements good for our health? I am confused with an advertisement I have seen on one site. They say fish oils are great for all of us, but fish can be contaminated. I can't get it. What do you think, should we take fish oil supplements?

some doctors says fish is healthy food to take, some one says they are not healthy food, fishes are good to eat for pregnant ladies.....
i think it is better to consult doctor.....