Kallgren Dermatology Clinic in Boulder cares about your skin’s health and knows that you do too! When you are picking a sunscreen to give you the best protection against skin damage and skin cancer is important to know why you are looking for certain qualities, as much as which qualities to look for. We believe that broad spectrum sunscreens, such as EltaMD Sunscreens are you best choice. Choosing a broad spectrum sunscreen is your best choice because they protect you from both UVA and UVB rays.


  • UVA rays are the rays that are responsible for the visible signs of aging in the skin (think ‘A’ for aging), including wrinkling and activation of melanin that results in a tan or freckles.
  • UVA rays are responsible for skin cancer and are intense through all daylight hours throughout the year.
  • Melanoma as well as basal cell carcinoma as well as squamous cell cancers are blamed on UVA rays.
  • UVA rays go through glass and clouds, so don’t think that a cloudy day means you don’t need sunscreen!


  • UVB rays are the type of ray that give you a sunburn.
  • At a cellular level, UVB rays kill skin cells and the immune system floods the area with blood to try to heal the damage which gives the skin a red appearance (think ‘B’ for burning.)


When you are packing up your car for an excursion be sure to throw in some sunscreen on top of your hiking poles, rain coat, and hat! Check back next week to learn about SPF ratings.