From the 21st day of embryonic development, the skin and brain begin to develop together, establishing a profound connection between our nervous system and our epidermis. The skin, enriched with 800,000 neurons, 11 meters of nerves, and 200 sensory receptors per cubic centimeter, is literally an extension of the brain. This connection underscores how our mental state influences the health of our skin and vice versa, illustrating the expression "to be on edge."

The constant communication between brain and skin reveals how our emotions and mental well-being can affect our skin. Studies on this two-way interaction seek to understand how our mental state can influence our skin and how targeted skincare can improve both our mental health and our skin's appearance.