I'm a big advocate of water - for humans AND cats. Especially older cats. Having seen the damage done by food contaminants in my older cats and the incredible benefits of immediate fluids, it doesn't take a rocket scientists to put 2 and 2 together.
So I feed wet food, have plenty of water available, and encourage my cats to play in their water, generally making for a fun kitty time. Kidney health is so important in older animals.
Many older cats already have some reduced kidney function. For that reason, diet and water consumption should be a pet parent's focus. Tied to this issue is also bowel movements. Hydration plays a very important part in keeping your cat's entire intestinal system working properly.
For a comprehensive article and a case study on colon issues caused from possible dehydration from the SunHerald.com, visit this link:
It shouldn't take much to convince anyone. But this does it.