In your 40s, skin cell turnover isn’t as fast as in your 20s or 30s. Your skin may begin to show sunspots, fine lines around the eyes, and loss of firmness to the skin. Steps to take: (1) Invest in premium cleansers that will target dull skin—a result of slow cell turnover. (2) Layer vitamin C serums under well-formulated sunscreens for doubly effective sun protection. (3) Focus on eye creams and serums that repair and replenish; consider a night cream or other advanced formulas to make the most of skin repair that takes place during the night.