Diet therapy in patients with rare diseases: a scoping review

This scoping review presents existing research evidence regarding diet therapy in patients with rare diseases (RDs).

Using the five-stage scoping review framework proposed by Arksey, O'Malley and Levac, we searched the published literature in PubMed, Web of Science, Royal Society of Chemistry, China National Knowledge Infrastructure, VIP Database and Wan Fang Database from January 2010 to November 2022. We selected diet therapy studies on 121 RDs, as categorised by the National Health Commission of China in 2018. Charts for research analysis were developed and used to categorise the data.

We ultimately included 34 diet therapy studies from 19 countries and territories for 10 RDs and 3 RD groups. RD diet therapy studies have mainly focused on inborn errors of metabolism (92.3%) and are common in Western countries. Most studies focused on diet therapy methods for RDs (44%). In addition, 29% of studies included diet therapy management, 15% included guidelines for diet therapy and 12% included the impact of diet therapy on patients.

Current diet therapies for RDs lack specificity and present with limited characteristics. Therefore, it is necessary to expand the scope and depth of future research and explore evidence-based recommendations and new diet therapies focused on patient needs and family support to provide a reference for improving the efficacy and safety of diet therapies for RDs.