If you only use one skincare product, make it sunscreen. UV radiation is responsible for 90% of visible skin aging.
UV Radiation Types
- **UVA**: Penetrates deep, causes aging and cancer (A = Aging)
- **UVB**: Causes sunburn and cancer (B = Burning)
Chemical vs Mineral Sunscreens
Chemical Sunscreens - Absorb UV rays and convert to heat - Lightweight, invisible finish - Active ingredients: avobenzone, oxybenzone, octinoxate - Apply 15-20 minutes before sun exposure
Mineral Sunscreens - Sit on skin and reflect UV rays - Active ingredients: zinc oxide, titanium dioxide - Work immediately - Better for sensitive skin
How Much to Apply
- Face: 1/4 teaspoon (two finger lengths)
- Full body: 1 ounce (shot glass)
- Reapply every 2 hours, or after swimming/sweating
SPF Myths Debunked
- **Myth**: SPF 100 is twice as protective as SPF 50
- **Truth**: SPF 30 blocks 97%, SPF 50 blocks 98%, SPF 100 blocks 99%
- **Myth**: You don't need sunscreen on cloudy days
- **Truth**: Up to 80% of UV rays penetrate clouds