What causes these sun spots in the first place?
These sun spots occur due to the amount of time spent in the sun when you were younger without wearing proper protectoin such as sunscreen and protective clothing. The UV rays of the sun can be very damaging to your skin and if you spent a lot time outdoors you are now paying the price.
They are caused by melanin production. Melanin is what gives your skin its color. The more melanin the body produce the darker the skin color will become. Sun spots are caused by a clump of melanin forming in particular areas.
As you get older your skin loses its usual ability to repair itself. If you spent a lot time in the sun when you were younger without properly protecting yourself then you will experience sun spot as you get older since that is when they will start to manifest themselves.
It would be ideal if sun spot could be prevented, and one such way to prevent sun spot would be to use a sunscreen with SPF 15 and above or stay out of the sun. Using sunscreen daily will certainly help to prevent sun spots. However if you already have them then you are looking for a safe and effective method to remove them. Sun spots took some time to become visible, therefore they will not go away overnight, however with the right treatment they will certainly disappear leaving you with beautiful looking skin. You have to work at it diligently.