What does the immune system have to do with play? The truth is, living a life without daily laughter, fun and outrageous energy is dangerous to your health. If you think that sickness is no laughing matter, you're probably suffering from Laughter Deficit Disorder or LDD If your fun and play muscles are under-exercised and life is much too serious, you need the 4 Vital Questions of The P.L.A.Y. Formula to show you how to let go and start enjoying life - and give your body the right energy it needs for healing. This new bestseller reveals the tell-tale signs of Laughter Deficit Disorder and proves you are biologically designed to be joyful... and healthy. LDD occurs when life seems too serious, stressful or overwhelming and we are unable to laugh or play enough. It can negatively impact our health in many ways. The shocking truth is that most people who suffer from it don't know it and don't know that it can be rectified."