An epidemic of allergies is spreading around the world. One billion people suffer from allergic diseases such as asthma, hay fever, eczema and food allergies. But this is just the tip of the iceberg. In this ground-breaking book, award-winning doctor Leo Galland reveals the shocking rise of hidden allergies that lead to weight gain, fatigue, brain fog, depression, joint pain, headaches, ADHD, digestive problems and much more. Astonishing new research shows how each of these is linked to the immune imbalance that is at the root of allergy.