SPF - Stay Pretty Forever - Defy Age With Food

The days are getting longer and the rays are getting stronger, time for an SPF refresher!

I’m frequently asked, “Do I really need sunscreen everday?” and “There are so many sunscreens, does it matter which one I use?” My answer is always, “Yes!”

Daily use of a broad-spectrum (UVA/UVB) sunscreen with an SPF of 15 or higher can help reduce aging of the skin caused by sun damage. Ultraviolet (UV) rays from the sun cause more than 90 percent of the visible signs of aging, which include wrinkles, rough patches, sagging, and skin discoloration.

Read that again! UV rays cause more than 90 PERCENT OF VISIBLE SIGNS OF AGING!

Many sunscreens do not block UVA radiation, which does not, primarily, cause sunburn but can increase the rate of melanoma and photodermatitis. The daily use of a broad-spectrum (UVA/UVB) sunscreen can address this concern.

What is SPF?

SPF, or Sun Protection Factor, is a measure of how well a sunscreen will protect skin from UVB rays, the kind of radiation that causes sunburn, damages skin, and can contribute to skin cancer.

If your skin would normally burn after 10 minutes in the sun, applying an SPF 15 sunscreen would allow you to stay in the sun without burning for approximately 150 minutes (a factor of 15 times longer). This is a rough estimate that depends on skin type, intensity of sunlight and amount of sunscreen used. SPF is actually a measure of protection from amount of UVB exposure and it is not meant to help you determine duration of exposure.

For best protection, experts recommend using a minimum SPF sunscreen of 15, applying the proper amount (2mg/cm² of skin, or about one ounce for full body coverage), and reapplying every 2 hours.

Most people under-apply sunscreens, using ¼ to ½ the amount required. Using half the required amount of sunscreen only provides the square root of the SPF. So, a half application of an SPF 30 sunscreen only provides an effective SPF of 5.5!

The SPF scale is not linear:
- SPF 15 blocks 93% of UVB rays
- SPF 30 blocks 97% of UVB rays
- SPF 50 blocks 98% of UVB rays
Therefore, one way of looking at this is that SPF 30 sunscreen only gives you 4% more protection than SPF 15 sunscreen.

Is more/higher SPF better?

Sunscreens with really high SPFs, such as SPF 75 or SPF 100, do not offer significantly greater protection than SPF 30. These numbers can mislead people into thinking they have more protection than they actually do. In order to have broad spectrum protection, the UVA protection should be at least 1/3 of the UVB protection. High SPF sunscreens usually offer far greater UVB than UVA protection, thus offering a false sense of full protection.

Bottom line: Adults should buy a water-resistant, broad-spectrum (UVA/UVB) SPF 30 sunscreen, reapply every two hours and use the right amount. For a sunscreen to work as advertised, apply a shotglass size amount for the entire body. Remember to re-apply sunscreen or sunblock 30 minutes before heading out and reapply every two hours.

Re-apply every 2 hours – no matter what SPF level you choose. I find it interesting that on every product I’ve seen, the direction to reapply every 2 hours is listed, but often so tiny it is missed. Reapplication is very important.

What I do – Personally, I use an SPF 30 sunscreen with the active ingredient zinc oxide, a natural sunscreen ingredient that physically—instead of chemically—blocks rays. Zinc oxide protects against both UVA and UVB rays. I begin my day with applying a lotion sunscreen before getting dressed and re-apply using a spray sunscreen throughout the day.