Moderation -- it's a straight forward word that guides a life well lived. No matter the endeavor, moderation is usually the best decision. It shows discipline and self-control. The practitioner of moderation governs his impulses, subordinating his emotions to his rational mind. The frequency in which moderation is described as a virtue/goal in diverse philosophies and religions attests to its value and timelessness.
Over indulging in anything, whether it be food, recreation, work, showering attention on a romantic interest, praising another, etc., often yields harmful results. The same is true for overly abstaining from something. Applying moderation to all that you do will help you lead a purposeful, happy, and healthy life. It certainly has in mine.