OBJECTIVES: To analyze the eating habits of the transgender population throughout the transition process, evaluate the nutritional requirements associated with gender transition, and reflect on the possible dietary challenges facing the transgender population. METHODS: A cross-sectional observational study was carried out with 146 individuals (58.90% transgender women [n = 86] and 41.09% transgender men [n = 60]) aged between 18 and 60 y old. Eating habits and nutritional intake were evaluated through a food consumption frequency questionnaire, 24-h dietary recall, and subsequent data entry using DIAL software. The anthropometric parameters weight and height were determined following the protocol proposed by the International Society for the Advancement of Kinathropometry and waist circumference was determined following the protocol of the World Health Organization. RESULTS: The study found that the diets of the studied population were unhealthy, with low fruit consumption (6.4 ± 4.39 rations in transgender men versus 11.5 ± 2.59 rations in transgender women, P = 0.758898323). Diets were high in lipids (43.62 and 44.24 in transgender women and transgender men, respectively) and protein (16.63 and 15.65 in transgender women and transgender men, respectively). Deficiencies in carbohydrates, folate, vitamin D, and minerals such as calcium, iodine, and zinc were detected along with an excess of selenium and especially phosphorus, which could affect hormone levels. CONCLUSIONS: Changes were detected as a result of their desire to look similar physically to the desired sex, they followed rules, ways of acting, and habits of primary socialization (learned in the family during their life). The analysis of the changes observed in our study revealed that during the transition process, eating habits changed based on information, often incorrect, obtained from the internet. Therefore, it is advisable to recommend implementing strategies that increase the consumption of fruits, vegetables and whole grains. In this study, we detected some nutritional deficiencies depending on the type of hormone treatment, so nutritional care must be individualized. Therefore, individualized nutritional interventions focused on increasing the consumption of fruits, vegetables, and whole grains should be carried out. It would be advisable to develop guidelines for nutritional advice, diagnosis, and intervention for transgender people based on scientific evidence as well as provide nutritional advice to the clinicians responsible for their follow-up.