I just heard that many insurance companies are coming down more on people who are overweight because of the claims that people are making. Like if you fall down during work due to being overweight, that seems to be a reason that they will charge you more. Has anyone experienced this?

Nope, but I did hear that some insurances were going to start making tiered insurance premiums. It wasn't just for overweight (obese) people though. It was also for people who smoked.

I can't remember if my insurance application asked for my weight but they definitely asked if I smoke which has reminded me to check when I can tick the no box

You mean like life insurance? My OH deals with the insurance. Not sure there was anything in the small print about my weight I hope not