When choosing sunscreen what SPF is best?

SPF is sun protection factor, meaning that the value equates to the multiplication of the time it would normally take you to burn without sunscreen. In other words, let’s say you do not wear sunscreen and get a sunburn within 10 minutes. Choosing a product with an SPF of 30 means it will take you 300 minutes (30 x 10 minutes) to burn. 

SPF refers to ultraviolet B (UVB) rays. UVB rays can cause sunburns, inflammation and hyperpigmentation. UVA rays penetrate deeper into the skin resulting in tanning and premature aging (wrinkles). UVA ray may also cause cellular damage and lead to cancer.  Broad spectrum products protect against both UVA and UVB rays.

(A little science fun, UVB are short wave and UVA are long wave.) 

When choosing a sunscreen look for a broad spectrum product with at least SPF of 30. Be aware that babies skin is highly sensitive and infants under 6 months will want to avoid sunscreen. It is best to keep babies in shade and in sun-protective clothing. Always follow the products instructions closely and reapply sunscreen after swimming or sweating. Per the FDA, products cannot be labeled water proof, and instead are labeled water resistant. Sunscreens that are water resistant mean they can last for 40 or 80 minutes and then need to be reapplied.