The research team found that three commonly used ultraviolet (UV) filters -- octylmethoxycinnamate, benzophenone 3 and octocrylene -- eventually soak into the deeper layers of the skin after their application, leaving the top skin layers vulnerable to sun damage. UV rays absorbed by the skin can generate harmful compounds called reactive oxygen species (ROS), which can cause skin cancer and premature aging. The researchers found that once the filters in sunscreen soak into the lower layers of skin, the filters react with UV light to create more damaging ROS.
The Cal team's research is the first to indicate that sunscreen filters -- intended to protect the skin from the very UV damage they apparently promote -- have reacted in such a way.
The researchers found that the filters only become damaging when they are soaked into the skin and another layer of sunscreen is not applied.
"This research confirms what the natural health community has been saying for years: That sunscreens are harmful to your health," said Mike Adams, a consumer health advocate. "The best sunscreen is actually achieved with a diet high in antioxidants," he explained. "When you eat berries, superfoods and fresh produce on a regular basis, these natural antioxidants are utilized by your skin to protect you from excessive ultraviolet ray exposure. Sunburns are caused more by poor nutrition than by UV ray exposure."
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