Sometimes called liver spots, they have nothing to do with the liver. They're caused by repeated sun damage.
"The cumulative effect of sun on your skin over the years leads to a change in your skin and the lay term for that is age spots," says Dr. John Swartzberg, head of the editorial board at the UC Berkeley Wellness Letter.
Swartzberg says age spots are harmless.
But he reminds us, sun damage is prime cause of skin cancer.
"So, even though age spots are not skin cancer and don't turn into skin cancer, we know that sun damaged skin, which age spots are a reflection is at risk for the development of skin cancer."
Swartzberg says there's no need to see a dermatologist if you've had that age spot for a long time, a doctor has looked at it before and said there's no need to worry, and it hasn't changed since then.
"On the other hand if that age spot starts to change or if you're developing new spots, it's best to get it checked out by a dermatologist."
Age spots can be removed. There are several options, including freezing, laser treatment, dermabrasion (sanding it away) and chemical peels.
For more information
American Academy of Dermatology: Age Spots