Book excerpt: Mast cell activation syndrome, postural orthostatic tachycardia syndrome and Ehlers Danlos syndrome are three syndromes which often appear together. On the surface they appear to be very different. After all, what can multiple allergies have to do with a fast heartbeat and a tendency to faint and how does it fit in with a debilitating connective tissue disorder? If there is a connection is there just one specific association or are there a number of different causes which come together to cement this eternal triangle? The impact of these syndromes on lives is profound not only in terms of lost working hours but of pain and restrictions which would test the patience and strength of most people. But are these syndromes a lifelong companion? Can diet influence genetic inheritance so that the propensity towards certain conditions is turned off. Maybe though, the answer is simpler than that. Could a deficiency of nutritional substances account for all of these syndromes by changing an outcome which has a knock on effect on the way the body responds downstream. All these questions are answered and more and accompanied by photos showing the impact of some of the symptoms of MCAS.The author, a medical nutritionist, takes us on a fascinating journey as she shows how simple deficiencies can account for all the syndromes occurring together and more importantly how easily they can be addressed. This is a book that can be read alone or complements other books in this series especially EDS and the Hypermobility Syndrome Diet which investigates the causes of hypermobility EDS and how diet may impact its manifestation. .