Did you know your skin regenerates in its sleep? At night, your skin switches from 'protect' mode to 'repair' mode, and it's time for the skin to recover from the day's stresses. Melatonin and human growth hormone (HGH) production are boosted, which in turn accelerates skin regeneration and the production of antioxidant enzymes. What do antioxidants do? They fight off environmental free radicals that are collected on your skin throughout the day. This is why proper cleansing and usage of antioxidants are essential in your nighttime regimen. A proper 8 hours of sleep is needed to regenerate the skin to its fullest potential.