Globally, elevated blood pressure is a leading cause of disease and disability and is estimated by the World Health Organization to cause 7.5 million deaths, accounting for 57 million disability adjusted life years. Elevated blood pressure is also a leading risk factor for coronary heart disease and stroke. Effective monotherapies and combination therapies exist for management of the disease, however poor adherence in part due to adverse events associated with drug therapy has ensured that the disease remains uncontrolled in a large majority of patients. Alternative therapies may hold the key to reducing blood pressure without the risks associated with drug- related adverse events. This project explores one such alternative, medically supervised water-only fasting with re-feeding on a plant-based (vegan) sugar free, oil free and salt free diet, assessing its clinical effectiveness, and cost-effectiveness in comparison to standard drug classes.