Investigating a Novel Therapeutic Diet on Food Additives for Ulcerative Colitis (The INNOVATE Study)

Background and aims The restriction of sulphate, sulphite and carrageenan food additives is a key strategy of a whole food diet approach called the ‘4-strategies to a sulphide-reducing” (4-SURE) diet, which has shown preliminary signals for clinical benefit. These additives are restricted due to their direct effects on mucosal inflammation in pre-clinical models and their ability to stimulate hydrogen sulphide production, but their effects in UC is poorly understood. Therefore, this pilot study aims to investigate the effects of a dietary therapy restricting sulphates, sulphites and carrageenan compared to a sham diet on disease activity in patients with mild to moderately active UC. Methods A randomised, single-blind, parallel dietary trial will be conducted to address these aims in 39 UC patients. Participants will be randomised to either the intervention or sham diet for 8 weeks, where they will be supplied with all of their meals and receive dietary education to implement their allocated diet. The primary outcome will consist of resolution of rectal bleeding. Changes in disease activity over 8 weeks will be also be assessed at via intestinal ultrasound (Milan criteria) and changes in faecal calprotectin. Other secondary outcomes will involve changes in faecal sulphide concentrations in response to diet, as a mechanistic biomarker of how the diet exert its effects. Anticipated impact If successful, the study’s first impact will be in providing insights for the cause and effect of food additives on colonic inflammation in UC. The data will provide the basis for powering a definitive study (if indicated). Data generated from this body of work will inform future guidelines for dietary management of UC, particularly in clarifying whether the need to restrict these additives, mitigating unnecessary dietary restrictions in this population.