Sep
08
2006

Sunscreen, the more the better

Ouch, she should have used more sunscreen: Courtesy  Wikipedia
Ouch, she should have used more sunscreen: Courtesy Wikipedia

Have you ever been sunburned? Did you wear sunscreen? A recent study published in New Scientist might change your mind on how frequently an individual should reapply sunscreen.

Researchers at the University of California Riverside stated, “if you apply sunscreen anything less than once every two hours, you might be better off not using any in the first place.”

Kerry Hanson and colleagues exposed human skin samples grown in a lab to UV radiation. The samples were covered with three common UV filters found in many sunscreens (benzophenone-3, octocrylene and octylmethoxycinnamate). Findings suggested the protective compounds sunk into the skin resulting in its protective capability being greatly reduced.

Researchers also found the skin samples tested contained more reactive oxygen species (ROS) when compared to skin exposed to UV without sunscreen application. ROS are free radicals that damage skin cells and increase the odds of skin cancer. At low levels, ROS are able to assist in cell signaling processes. However, at higher levels ROS damage cellular macromolecules and could lead to apoptosis (programmed cell death).

For now the researchers advise to use sunscreens and reapply them often. The Skin Cancer Foundation recommends reapplying sunscreen every two hours. Active individuals are advised to reapply even more frequently due to sweat washing away sunscreen.

Your Comments, Thoughts, Questions, Ideas

Author123's picture
Author123 says:

I got sunburned last summer,and my nose got all BUBBLY!!!!!

posted on Sun, 09/10/2006 - 9:01am
Liza's picture
Liza says:

Researchers at the Dana-Farber Cancer Institute have developed a compound, called forskolin, that seems to protect red-furred mice (who have the same genetic difference that causes red hair and pale skin in humans) against sunburn and precancerous cell damage. It also creates a sunless suntan. (Their findings were published in Nature 2006; 443:340-44.)

Note: the study was done only in mice. It will take years to develop a product that's proven safe and effective in humans. Until sunscreen with forskolin hits the drugstores, slather on conventional sunscreen and wear a hat.

posted on Thu, 09/21/2006 - 1:52pm
Anonymous's picture
Anonymous says:

“if you apply sunscreen anything less than once every two hours, you might be better off not using any in the first place.” Does not make sense!!! Apply and reapply often for better protection- but to suggest not reapplying is worse than applying even once- off target.
Just like starting smoking- you will regret sun exposure- they all do in my clinic with the diagnosis of skin cancer.

posted on Thu, 05/31/2007 - 12:08am

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