Dogs Eating Grass?

[maggiemcgill]

Does anyone know why dogs eat grass? Mine does it fairly often, but when he's under the weather he seems to do it more.
Here's the yucky bit; he has been a bit poorly for a day or two and has been munching more grass which can clearly be seen in his poo!
I believe it has something to do with digestion but how do dogs instinctively know how to do this, when the grass appears not to digest at all?

[lajohn]

dogs eat grass to purge and clean their stomach.

[rcl1]

Cats do the same thing thing.

[andy-hughes]

It's the doggie and puss equivalent of two fingers down the throat.

The animal knows its stomach needs emptying, and the quickest way to do that is to eat grass, which instantly irritates the stomach, and is ejected, along with the remaining contents, and hopefully the irritant.

[vicky2498]

Yeah dogs do this to make them self sit my dog does it alot he also eats his own poo sometimes. just watch your dog when you let him out and try to stop him doing it

[vicky2498]

sorry they dont do it to make them selves SIT i meant sick lol

[greenrook]

Our vet tells me dogs appear to know instinctively when they need folic acid, of which grass is apparently a source