Abstract
BACKGROUND AND AIMS: Ulcerative colitis (UC) is a chronic inflammatory bowel disease with a relapsing-remitting course that often requires hospitalization during flares. While prolonged fasting has traditionally led to high-calorie intravenous nutrition, excessive caloric intake may induce hyperglycemia, increase infection risk, and inhibit autophagy. This study aimed to evaluate the impact of a short-term, calorie-restricted regimen (≤400 kcal/day), designed to promote autophagy, on clinical outcomes in hospitalized patients with UC. METHODS: A retrospective analysis was conducted on 38 patients admitted for UC exacerbation between January 2022 and December 2024. Patients were categorized into a calorie-restricted group (≤400 kcal/day) or a standard nutrition group (>400 kcal/day) based on their total caloric intake. The calorie-restricted group received only intravenous fluids and noncaloric beverages. The primary endpoint was clinical remission at day 14, while secondary endpoints included the length of hospital stay and incidence of adverse events. RESULTS: The clinical remission at day 14 following treatment initiation was significantly higher in the calorie-restricted group (86% [12/14]) compared to the standard nutrition group (42% [10/24]) (P < .05). The mean duration of hospitalization was also significantly shorter in the calorie-restricted group (11.0 ± 3.3 days) compared to the standard nutrition group (22.1 ± 8.9 days) (P < .01). The calorie-restricted group experienced mild, transient adverse events but no serious complications. In contrast, the standard nutrition group experienced serious adverse events such as catheter-related infections and myocarditis. CONCLUSION: Caloric restriction during hospitalization for UC exacerbation may be associated with increased clinical remission and a shorter hospital stay. That nutritional strategy offers a potentially novel and cost-effective approach distinct from conventional bowel rest. Further prospective, multicenter studies are warranted to validate these findings.