food for cat..

Oh, another thing: stick to dry food. Cats usually love canned food, but it has a high rate of humidity, making your cat drink less water.. This to can induce kidney problems in later years.

But there's nothing wrong in offering them some canned food once in a while, but only as a treat:P

Although looking at the ingredients list is one way to go, many companies will split up the types of grain so that they appear in smaller amounts and therefore show up closer to the bottom of the list.
You should be aware that there are actually obligations for petfood companies stating that there must be a certain amount of meat in the product in order to use certain words in the name. For example is you buy a food that has beef in the name (ex. my brand beef cat food) that means that there is atleast 90% beef in the total mass. As opposed to buying beef flavor dog food which would contain less than 3% beef (ex. my brand beef flavored cat food).
I am going to be quite honest that in my 4 years of study to obtain my animal nutrition degree there is not significant evidence that having grain mixed into a meat diet will harm a cat.
And yes a cat will drink less water on a canned diet because canned diets are usually composed of about 75% water. Therefore they get a large amount of their daily water intake from their food. It has also been shown that cats are extremely variable in the amount of water they will consume in a day. It is believed that they evolved from desert animals and therefore have become accustomed to getting a majority of their water through their food.
That said they can not survive on a diet that is devoid of meat. Whatever cat food you buy make sure that it has been tested under AAFCO (association of american feed control officials), and you will be sure that it contains everything which your kitten/cat requires for their appropriate life stage.