As I'm sure you know, appearances don't mean squat when it comes to our health.
A few years back a good friend of mine - mid-50's at the time - had just spent the afternoon putting in the docks at his cabin. He looked like he was in better health than his 2 sons that helped him.
Later that day his wife wondered why he was taking so long in the shower and went in to check. She found him lying on the shower floor, the fatal victim of a massive heart attack.
Last month a co-worker came in on a Friday and told us that her husband, a big, strong, softball-playing, motorcycle-riding construction worker hadn't been feeling right for a few days and decided to go to the doctor. He was diagnosed with cancer. They were told that it was treatable and had an appointment for the following Monday to set up a treatment plan. By Sunday afternoon he was gone. The entire episode took less than a week.
Looks can be very deceiving.