There are some major problems with the SPF rating system that is printed on labels for sunscreens in the US:
1. The Sun Protection Factor (SPF) is a rating based on the amount of time it takes for skin to turn red (damaged) when exposed to ultraviolet radiation type B.
2. No required product rating exists for damage to skin and DNA from ultraviolet radiation type A.
3. Both UVB and UVA cause skin cancer, sunburns, wrinkles, brown spots, collagen break-down, bruising (solar purpura), and pain.
4. 85% of the ultraviolet radiation that reaches earth's surface is UVA.
5. Some of the most commonly used chemicals in sunscreens cause harm when they get into the environment, i.e. coral reef, aquatic wildlife, and one has shown it causes cancer in laboratory test animals.
So, here are my 22 years' worth of meaningful skin protection recommendations:
1. Pick a sunscreen that is mineral-based (zinc oxide), has an SPF of 30-50, and feels good on your skin. Zinc blocks (reflects) UVB and UVA.
2. Nourish and hydrate your skin and neutralize oxidative damage at the beginning and the end of the day. Build your skin barrier and reduce free radical damage.
3. Wear protective clothing, full-brimmed hats, sleeves when driving, and use a sun umbrella if you're over-exposed.
That's where we are, and where we've been. Be safe, don't get skin cancer.
