How does caffeine affect you skin?

Causes drying. Because caffeine acts as a diuretic (makes you urinate) it can cause dry skin. Small amounts should not be a problem but large amounts can cause significant drying of the skin.
Caffeine ; Skin. The connection between caffeine and acne has been a topic of hot debate over the years, with inconclusive results on both sides of the argument. However, some experts believe that while caffeine may not be a cause of acne, it could worsen the already existing condition.