Cat losing weight yet healthy?

Our cat has always been on the fat side. We tried everything over the years to curb this, but overall he maintained being a fairly big cat. He's around 13 years old now, and I know his years are dwindling down, but he seems to be in perfect health--healthier than before even. He's lost a bunch of weight over the past couple of years, and for the first time since he was a kitten, he's lean again. Yet, he appears fine. He's light on his feet, almost nicer, and he even caught a squirrel outside (first thing he's ever caught in his life either). No sign of worms, no sign of discomfort, no sign of pain. Should I be worried, or is he "just getting old" and losing weight is a natural part of this? Thanks!

When they start losing weight, they're never all right. Thorough, comprehensive testing is in order.

Well, I hate to tell you this. Three and one years ago I lost two, formerly overweight, male cats to cancer. Neither showed any symptoms until close to the end except rapid weight loss. Both were difficult to diagnose at first.

One I was able to keep going with medication, comfortably, for 20 months, after many tests to get the diagnosis of lymphoma. This was much longer than the specialists predicted. He was 11 when he got sick, and I had him since he was a kitten.

The other I only had 10 months, and he had been a stray. He didn't make it out of exploratory surgery for tumors. He was estimated at about 12 years old.

This was so devastating that I have purchased a baby scale, and I weigh my cats once a month.

Your cat may be fine, and I sure hope so, but I'd get him checked out.

Robin

I would recommend full bloods including thyroid to be on the safe side.

It's hard to say, he could just be getting skinnier as he's getting older like you said, or he could have a grave medical condition like others have said.
What food is he on? Did you change it a few years ago?