Hormone therapy, health outcomes and the role of nutrition in transgender individuals: A scoping review

Objective: The objective of this scoping review is to describe the extent, range, and nature of available literature examining nutrition-related intermediate and long-term health outcomes in individuals who are transgender. Specific sub-topics examined include 1) dietary intake, 2) nutrition-related health disparities, 3) validity and reliability of nutrition assessment methods, 4) the effects of nutrition interventions/exposures, and 5) hormone therapy. Methods: A literature search was conducted using MEDLINE, Embase, PsycINFO, CINAHL, Web of Science, and other databases for peer-reviewed articles published from January 1999 until December 5, 2019 to identify studies addressing the research objective and meeting eligibility criteria. Conference abstracts and registered trials published or registered in the five years prior to the search were also included. Findings were reported in a study characteristics table, a bubble chart and heat maps. Results: The search of the databases identified 5403 studies, including full peer-reviewed studies, systematic reviews, conference abstracts and registered trials. Following title/abstract screening, 189 studies were included in the narrative analysis. Ten studies reported dietary intake in transgender individuals, 64 studies reported nutrition-related health disparities in transgender compared to cisgender individuals, one study examined validity and reliability of nutrition assessment methods, two studies reported nutrition interventions, and 127 studies reported on the intermediate and health effects of hormone therapy. Conclusion: Individuals who are transgender have unique nutrition needs, which may vary according to the stage and type of gender-affirmative therapy that they are undergoing. There is scant research examining effective nutrition therapy methods for nutrition professionals working with transgender individuals. More research is needed in order to inform evidence-based clinical practice guidelines for nutrition practitioners working with transgender individuals. (C) 2020 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.