Stephen Barrett has described "leaky gut syndrome" as a fad diagnosis and says that its proponents use the alleged condition as an opportunity to promote a number of alternative-health remedies – including diets, herbal preparations, and dietary supplements.[4] In 2009 Seth Kalichman wrote that some pseudoscientists claim that the passage of proteins through a "leaky" gut is the cause of autism.[5] The belief that a "leaky gut" might actually cause autism is popular among the public, but the evidence is weak and what evidence exists is conflicting.[6]