The computer-generated images show the 27-year-old singer with deep-set wrinkles, drooping eyelids, under-eye bags, and sagging and discoloured skin, thus warning youngsters of the dangers of sunbed.
One set of images shows how the fresh-faced Thom would look at 57 as a result of natural age progression, while the second set shows her at the same age after decades of over-exposure to ultraviolet (UV) rays - resulting in 70 per cent more wrinkles.
According to the charity using a sunbed before the age of 35 increases the risk of skin cancer by 75 per cent.
Thom, who was herself a regular sunbed user is shocked to see the images.
"I'm in a state of shock and the thought of looking like this at 57 is terrifying. Having seen these images I can honestly say I am never going to use a sunbed again," the Telegraph quoted her as saying.
"You can so easily get brown from a bottle these days, there is just no point in ruining your looks and risking skin cancer by using sunbeds.
"I hope the horrible image of me will make other young people think twice before they next use a sunbed," she added.