GI symptoms in patients were seen in 12% after COVID-19 and 22% as part of long COVID. Loss of appetite, dyspepsia, irritable bowel syndrome, loss of taste, and abdominal pain were the five most common GI symptoms of long COVID. Significant heterogeneity and small number of studies for some of the analyses are limitations of the systematic review.
IBD is an autoimmune condition, which studies have shown increases a person’s chances of Long Covid. Now doctors are seeing both de novo IBD after Covid and worsening of existing IBD. (see this thread). More research is needed. Another reason for high grade mask & ventilation.