[Reason for consultation: Weight loss]. / Motivo de consulta: pérdida de peso.

BACKGROUND AND OBJECTIVE: Unintentional weight loss is frequent reason to visit a doctor and it has multiple diagnostic possibilities. The objective of this study is to examine the background of the patients who seek consultation for weight loss and to establish the relationship between weight loss and neoplasia. METHOD: An analysis was performed on the demographic data, quantified weight loss, accompanying symptomatology, and diagnosis of patients who sought medical advice for unintentional weight loss during the year 2015. RESULTS: A total of 226 patients were included, of whom 44.2% of them had an intentional weight loss ≥ 5% in 6 months. The most frequent diagnosis in this group was a neoplasia, whereas in the rest of patients the most common diagnosis was a gastrointestinal disease. In light of this study we can conclude that there is a relationship between unintentional weight loss≥5% and the presence of neoplasia. CONCLUSION: An unintentional weight loss greater than 5% in the previous 6 months is associated with the presence of neoplastic diseases, and therefore requires further diagnostic study.