I am just about to start taking Shiseido Pure White pills. I would like to know if during my medication will it be harmful if I expose myself to the sun? I will be going to the beach this summer and would really like to know if I should use an umbrella < and spoil all the fun>

No some sun exposure will not be harmful really but it will slow the process of your skin lightening. Sun exposure must be limited when using skin lightening products. If you are going to the beach make sure you wear sunscreen with SPF 70 that blocks both UVB and UVA rays. Apply regularly and re-apply after toweling.

Here is a site I found that was helpful to me
Sunscreen Facts and Myths
Hope that helps