I have just responded with a long reply regarding the necessity, for the health of your pets, of feeding them a raw meat and bones diet. I will repeat it here. (I have added some new information here.)
My cats, in a calendar - flip through to see their Vibrant Health!
I must STRONGLY suggest you research the feline diet and stop feeding your cat commercial dry food (Purina, Friskies, or the Veterinarian prescriptive diets, etc. e.g.). Cats require a raw meat and bones diet; there are many resources online about this.
(The context of the post I replied to was about how cute it was the cat was eating grass, and did not heave very often ...)
One of the reasons your cat is eating grass like a fiend is because she is undernourished. She may still like grass, but her gut is - trust me - not healthy on Purina or other commercial food products. Look up BARF, it stands for Bones and Raw Food - for dogs and cats there are specific NATURAL diets. Cats, even more than dogs, need raw foods. Look at the ingredients in the bag of what is considered a 'good food'. It is not. What is the main ingredient? Corn? Flour? chicken 'by products'? These are NOT healthy foods for a cat.
Please, I am glad your cat is healthy now, but for her long-term health please research. You may find it is less expensive. You will also find that the pet food manufacturers and most veterinarians (who make a lot of money selling commercial foods) will tell you not to feed your animals raw meat. They are simply wrong. Think about it ............
In the wild (and cats are not that long domesticated to have changed their gut), cats do not cook their food or eat tortillas or corn on the cob, or meat 'by products'. They eat the organs and muscle meat of small animals. You can replicate this. Chicken necks (always raw) are excellent for their teeth as well. I raised Abyssinians and they never had a problem with their teeth and their health was excellent on a diet of raw meat and bones. Strong and sharp teeth with no tartar and no bad breath. The bones keep the teeth and gums and mouth healthy. This will save you a lot of money and your animals a lot of pain!
You will also find that cats on a natural diet poop less and their waste does not have a bad odor. For male cats, this is especially important as the dry foods can have a very damaging effect on their urethra.
There is an excellent yahoogroup on this ... https://groups.yahoo.com/neo/groups/rawpaws/info
There are simple recipes you can make up yourself, and freeze, and save money, and the group is full of helpful people with a lot of experience for transitioning adult animals to a natural diet.
Please, I love cats, and at every opportunity, yes, I do do this and recommend pet owners read up on natural alternatives to what the pet food industry is pushing as 'good food'.
May you and your kitties enjoy a long and healthy life together.