The 411 on Sunscreen

I met Catherine Markham,  during a visit to SkinMedix, my favorite skin clinic in the South Bay. I’ve been to Catherine several times now for facials and I’m absolutely addicted.  Along with regular facials, I use sunscreen daily. However, I always find it challenging to figure out exactly how much coverage I need to be protected. Read on as Catherine, gives us the 411 on SPF, UVA and UVB’s:

I get a lot of questions about sunscreen and SPF. Prior to research and study, I didn’t know the difference between SPF 8 or 100 and more importantly, I wanted to know what ingredients are key to block UVA and UVB rays.

UV or Ultraviolet light are made up of two rays of radiation that reach the skin, they are UVB rays which penetrate the epidermis (the outer layer) and burn the skin. UVA are rays penetrate deeper into the dermis and age the skin. Think of UV(B as Burn) and UV(A as Aging) causing wrinkles, photo-aging, free radicals and leathery skin.

 The 411 on Sunscreen


Your skin starts to age from your first sunburn. Babies aren’t born with freckles, right? Your sun damage will surface 10 years after those burns. Everyone needs to wear sunscreen. You may think if you are darker toned that you don’t need to wear it but you do, as it prevents aging and skin cancer. Darker skin tone does have more melanin so you may appear darker and may not burn, but you still need to protect your skin. If you have acne scars the sun will make them darker and hyperpigmentation will occur and darken every time you don’t wear sunscreen. Some women also have melasma which will worsen in the sun.

So when choosing a sunscreen start with an SPF 30-50. No need to go any higher because this is enough to block UVB rays. The main ingredient you will want to see is zinc oxide or titanium dioxide. This blocks the UVA rays. Apply a half hour before you go to the beach so it’s already absorbed and protecting your skin. Apply every two hours if you are at the beach. One of my personal favorites is SkinCeuticals Physical Fusion UV Defense SPF 50. Its is a broad spectrum tinted facial sunscreen that protects skin from the sun and provides sheer coverage. Ingredients include Zinc oxide and titanium dioxide. It feels light and dewy on the skin and it’s also great for no-makeup days when you want to sheer, whispy light coverage.

It is also available at Skin Medix in Hermosa Beach.Treatments that will help erase years of skin damage are IPL, ViPeel, Cosmelan and regular facials to include Microdermabrasion, HydraFacial, and Micropeels. Call for a complimentary skincare consultation with Catherine Markham at Skin Medix in Hermosa Beach 310.374.6600.


  1. katie says:

    i love any good reliable info i can get about sunscreen, thanks for the post! love it!