When shopping for a sunblock, you want to make sure you are protecting your skin from the harmful rays of the sun; so you check for a sunblock with a high SPF. If only it were that simple! Your sunblock may not be protecting you the way you might think it is, regardless of the SPF! The difference is in the ingredients, not so much the SPF. Most sunblocks are chemical blocks, which means they absorb into the skin and work by absorbing the suns rays. They generally take at least 20 min before they even start becoming effective. The other type of sunblock is called a physical block. A physical block actually “blocks” the suns rays and begins working immediately. There are 2 active ingredients to look for that ensure you are totally blocking out UVA and UVB rays; Zinc Oxide and Titanium Dioxide. SkinMedica makes a great one called Environmental Defense Sunscreen! The bottom line is read the labels because all blocks are not created equal.