Several studies established a link between diets high in complex carbohydrates to negative health conditions. The gluten-containing grains (wheat, but also rye, barley, and oats) have at least fifteen opioid sequences, which are strongly addictive, morphine-like substances that have powerful psychoactive properties and produce severe neurological disorders, constipation, urinary retention, nausea, vomiting, cough suppression, and other Gluten intolerance or celiac disease. According to these studies, all the above mentioned products contributes to or causes a wide range of other diseases, including asthma, arthritis, chronic fatigue, Crohn's disease, Type 2 diabetes, depression, eczema, fibromyalgia, irritable bowel syndrome, migraines, lymphoma, and gastrointestinal cancers. Gluten intolerance may also be connected to autism, schizophrenia, and several autoimmune disorders.