10 smart sunscreen tips

1. Know your sunshine
The sun produces two types of ultraviolet rays and both are believed to cause skin cancer:

UVA penetrates deep into our skin and it’s difficult to get full protection from these rays.

UVB doesn’t penetrate the skin as deeply and so are the rays that turn us red.

2. Know your sunscreen
Bottles sun protection comes in two forms:

Sunscreens are chemicals that absorb the radiation as it hits our skin. Broad spectrum sunscreens offer protection about both UVA and UVB – although UVA protection is limited.

Sunblock physically block both kinds of UV rays by reflecting them away from the skin. The most popular are zinc oxide (ZO) or titanium dioxide (TiO2), both which leave a tell tale white mask on the skin. Newer formulas have been micronized to become transparent. And, just to confuse us, they are also called sunscreens.

3. Understand SPF
Sun Protection Factor (SPF) measures the UVB rays NEVER UVA! That classic formula of multiplying the SPF factor by ten to get the length of time doesn’t work! Most sunscreens give between 60 to 90 minutes of protection so SPF should be used to determine how much UVB is blocked:

2 SPF blocks 50 percent

10 SPF blocks 90 percent

15 SPF blocks 93 percent

30 SPF blocks 96.67 percent

50 SPF blocks 98 percent

4. UVA protection
Since UVA rays are impossible to measure accurately, the FDA created the following UVA ratings:

One star: low UVA protectio

Two stars: medium protection

Three stars: high protection

Four stars: highest protection available in an over-the-counter (OTC) sunscreen product.

The European rating is low, medium or high. Canada has yet to adopt a rating for UVA protection. Mexoryl SX, a popular UVA blocked used in Canada and Europe for many years has just been approved for use in the USA. Find out more about the sunscreens available with Mexoryl SX at Makeup Alley.

5. Use the teaspoon rule
To prevent sunburn use the teaspoon rule: one teaspoon per body section. (One for face and neck area, one for the front, one of for the back, one for each exposed arm and leg.) A typical plastic twist-off cap is about a teaspoon worth. Pay attention to those classically overlooked areas: ears, nose, lips, feet and toes.

6. Treat your sunscreen properly
Store your sunscreen in a cool place -- not in your car on a sunny day. Heat does strange things to the chemical compounds, rendering them ineffective. Most of us don’t realize sunscreen has a shelf life so checks yours for the expiry date. It won’t work very well past the due date.

7. Be realistic
If you burn easily then the only safe protection is to stay out of the sun during peak hours between 11 a.m. and 3 p.m.. Afternoon siestas were invented for a reason. Sunscreen rubs off easily so should be reapplied every two hours even it claims to be sweat or water resistant.

8. Buyer beware
Don’t believe all the claims by manufacturers. An investigation by the Environmental Working Group (EWG) found 4 out of 5 of the 952 name-brand sunscreens tested were inadequate. Check with the Skin Deep, Cosmetic Safety Database to see how your brand measures up.

9. Read the labels
Protection has a downside. Micronized ZO and TiO2 sunblock may pose a threat by being small enough to be absorbed through the skin into the bloodstream. The Australian government recommends nothing smaller than 100 nanometres (nm). Powder and sprays should be avoided because the particles are easily inhaled.

Hormone disrupting chemicals such as Benzophenone, homosalate and octyl methoxycinnamate (also called octinoxate) and DNA disruptors Padimate-0 and parsol 1789 (aka avobenzone) are also killing our marine life and coral reefs. Doctors are recommending you don’t use them on small children.

10. Let your skin breathe
Canadians and Americans are so dangerously low on their Vitamin D that many doctors are recommending "safe sun" -- 15 minutes without sunscreen a couple of times week to get your dose of the sunshine vitamin. Read more about Vitamin D.

Shelagh McNally is the editor of Green Living Online. She dreams of an even tan to replace her freckles.