Here's more evidence that sleep deprivation can exacerbate inflammatory bowel disease, which includes ulcerative colitis and Chron's disease. A study was published in Sleep Medicine where rats who were given a substance to induce colitis (DSS, dextran sodium sulfate). Control rats that were deprived of acute sleep deprivation or chronic sleep deprivation had no signs of colitis. Rats on DSS developed colitis, but acute sleep deprivation showed histologic signs of additional inflammation on histology, but showed no clinical symptoms such as weight loss. However, rats subjected to chronic sleep deprivation showed increased histologic inflammation, as well as clinical symptoms. This study is a follow-up to a previous study that showed that patients with inflammatory bowel disease had significantly more sleep disturbances.