Although there are now two Food and Drug Administration (FDA)-approved treatments for severe alopecia areata (AA), many patients still resort to non-medical therapies and lifestyle modifications such as diet and nutrition. The goal of this study was to evaluate the sources and types of dietary and nutritional advice for patients with AA. We distributed a cross-sectional national survey using the National Alopecia Areata Foundation's email list-serv between August 2022 and January 2023. Most respondents were White (76.3%), employed (58.3%) females (84.4%) with a mean age of 52 years. 163 (19.1%) respondents reported receiving diet and/or nutritional advice and 418 (49.5%) respondents reported searching for diet and/or nutritional advice to help with their AA; the most common source of advice was online. The most common dietary changes were the use of vitamins or supplements (30.6%), adherence to diets (23.2%), and the addition of specific foods (21.4%). 209 (50.2%) respondents reported no change in their disease and 197 (47.4%) respondents reported no change in how they felt about their disease compared to before they tried the change. Many AA patients search for or receive unsolicited dietary and nutritional advice and subsequently modify their behavior to manage their disease. However, the efficacy of these changes is unclear. Providers should be mindful of the sources through which patients obtain treatment information as well as the lifestyle changes patients make to counsel patients with evidence-based information. Further investigation is needed to better characterize the direct and indirect costs of dietary and nutritional modification in the treatment of AA.