25 Jan SPF Smarts
Thinking of hitting the slopes or a beach holiday to chase away the winter blues? Do you want to maximize and prolong the benefits a procedure such as a chemical peel or laser resurfacing (e.g.PicoSure or Fraxel)? Or, do you just want to protect your skin from the daily assault of sun and wind?
Today’s topic of sunscreen use and safety is a timely one.
90% of the signs of aging skin as well as 90% of skin cancers come from ultraviolet light exposure. A combination of protection from the ultraviolet rays (both UVA and UVB) of the sun, protective clothing, and smart behavior while in the sun can save you a lot of anguish and money.
Sunscreen ingredients can either act a physical blocks to UV light and reflect the rays away from the skin’s surface or they can act as filters, neutralizing the effects of sunlight once it penetrates the skin. Zinc oxide and titanium dioxide act as blocking agents. Being inert chemicals they are relatively free of side effects. Advances in delivery of these sunscreen ingredients have gone a long way to make their use more cosmetically acceptable avoiding issues feeling encased in heavy white gunk.
That said, the use of any sunscreen is better than none.
Recent lay publications have raised the question of the safety of ingredients such as oxybenzone. An estrogen effect was found when megadoses of oxybenzone were fed to laboratory rats. The amount of oxybenzone ingested by the rats equated to 200 years of daily application of the chemical to the skin. Eating a chemical is quite different than applying it to the skin. Studies of human application of oxybenzone in concentrations higher than that allowed in sunscreens show trace levels of the chemical in volunteers’ urine, but no difference in hormone levels that can be attributed to the chemical. The body effectively excretes the chemical.
Studies have also failed to show that another chemical ingredient, retinal palmitate, increases skin cancer risk.
Regardless of weather or time of year, sun avoidance should be on everyone’s mind. Some 80-90% of the sun that we incur in the course of a lifetime comes from activites such as walking from the house to our automobile – not when we actively pursue the sun. Cloud cover is not protective; 80% of the sun’s UV rays penetrate dense cloud cover.
SPF ratings apply only to UVB rays, the shorter rays of ultraviolet light that cause redness of the skin as well as the development of basal and squamous cell carcinomas. SPF 15 blocks 93% of UVB rays for 2 hours; SPF 30 blocks 97% and SPF 50% blocks 98% for the same 2 hour time frame. Frequent reapplication of sunscreen is important for optimal protection. Be generous in the amount that you apply.
People with tans and people of color should also use sunscreen. Black skin offers at most the protection of SPF 4.
Vacationers beware! Reflective surfaces such as snow, water, and sand will intensify the effects of the sun. Use your sunscreen throughout the day, wear protective clothing (e.g. hats with broad brims, long sleeves and pants), choose your hours of exposure as best you can (avoid the hours of 10am-2pm), seek shade, and don’t forget to protect your lips and eyes.
Be smart and have fun! I myself am off to the slopes. With broad spectrum sun screen, of course!