Intellectual disability (ID) is a complex condition that has not aroused very much interest in the health sciences and medical fields. As a result, a large part of the responsibility for caring for individuals with ID has fallen in the areas of education, social services and volunteering. Nevertheless, intellectual disability is a very significant health problem, whether because of its prevalence, the costs to the public health system, the families and society in general or due to related health complications. ID should be a priority area of study and action in the health field. This article reviews the conceptual, diagnostic and etiological problems that affect intellectual disability, as well as factors related with the health of the persons who are affected. In addition, some recommendations are outlined for improving health care for this population group.