LEVEL 1
UV and Photoaging Science
"It's cloudy today, so I don't need sunscreen." "I'm indoors, so I'll be fine." — Have you ever thought something like this?
In reality, UV rays reach the ground even on cloudy days. On lightly overcast days, approximately 80-90% of UV radiation still reaches the earth's surface. Window glass also allows most UVA to pass through.
According to dermatological research, approximately 80% of skin aging (wrinkles, dark spots, sagging) is caused by "photoaging" from UV radiation. Natural aging due to chronological age actually accounts for only about 20% of total skin aging.
In other words, sunscreen is not something you apply "to avoid getting tanned" — it is something you apply every day "to prevent skin aging".
For daily use, choose sunscreen with SPF 30 or higher and PA+++ or higher. SPF measures protection against UVB (short-wave UV), while PA indicates protection against UVA (long-wave UV).
Higher numbers don't necessarily mean better. What matters most is "applying the right amount every day and reapplying regularly." Rather than applying once in the morning and forgetting about it, reapplying every 2-3 hours maintains its effectiveness.
Sunscreen is the simplest and most effective form of anti-aging care. Why not make sunscreen a daily habit starting today, regardless of weather or season?
KAIAN develops skincare products based on photoaging research.
Please feel free to contact us with any questions.
