Cats can sense illness?

New here! I'm wondering if my grandma's cat is affected by her alzeimer's. She was diagnosed over a year ago and coincidentally her cat began to lose a lot of weight and becaome even pickier with his food. She and the cat adore each other but they both seem to be going down together. Granted he was already pretty old but I was just wondering, especially since I read this BBC article:
http://news.bbc.co.uk/2/hi/uk_news/magazine/6919063.stm

Any thoughts or insights? Thanks!

I was very sick several years back and the doctors never did diagnose me with anything. I suffered from extreme fatigue and spent most of a month on my couch which is a very boring existence. My adult males cats would take turns sitting with me. I was never for a single moment without a cat. They would trade off "mom-sitting" duties.

That being said, they never did get ill. Of course, neither of them are seniors.

I think cats know more than we do

I had surgery on my hand about a month ago. 3 days after surgery, my Muddy's FLUTD problem surfaced and I had to make an emergency trip to the vet. Muddy is a sensitive cat, and got upset when I was not normal. As the hand slowly healed, he's calmed down again.

Absolutely know that cats sense illness or injury in people. The closer they are to you, the more strongly they seem to react to it.

Wow thanks for sharing your experiences, very insightful! Cats are quite amazing and very sensitive to these things aren't they.