Ettelbruck

Long COVID syndrome (LCS) is a condition where symptoms like fatigue, breathing difficulties, pain, depression, anxiety, and cognitive issues persist for more than 2-3 months after a confirmed COVID-19 infection. This trial explores using a medically supervised fasting method, the Buchinger-Wilhelmi method, to see if it can help improve these symptoms by affecting immune responses and metabolic functions. The study aims to assess the feasibility of a 7-day ambulatory fasting intervention and its effects on clinical, biological, and psychological health over 4 weeks. Participants will undergo a structured fasting protocol starting with a bowel cleanse followed by 7 days of fasting under physician guidance. During fasting, they will consume up to 350 kcal daily from vegetable broths and juices, along with calorie-free water or tea. The study includes preparation days with reduced food intake and avoidance of stimulants. Support will be provided through face-to-face consultations and a smartphone app to monitor adherence via urine ketone measurements. Throughout the 4-week study, participants will have blood drawn, stool and urine samples collected, and saliva taken for analysis. They will complete questionnaires through a smartphone app covering fatigue, quality of life, functionality, anxiety, depression, mood, and blood pressure. Researchers will monitor safety, metabolic changes, immune activity, and microbiome composition. Data will be securely stored, and participants will receive detailed information and support during the trial period.