Anorexia nervosa is an eating disorder characterized by restrictive eating and an intense fear of gaining weight. It is a disease with an increasing incidence during the last few decades, and represents a complex psychiatric condition which includes secondary amenorrhea, nutritional and metabolic damage, and impaired endocrine panel up to bone loss as well as cardiac, gastrointestinal and hematological complications. This is a narrative review which includes an update on this eating disorder from the perspective of an endocrine panel of anomalies, especially of the skeleton, considering the pressure of the recent global COVID-19 pandemic changes. Practically affecting every organ, anorexia nervosa needs to be taken into consideration during the pandemic period because of the higher risk of relapse due to new living conditions, social distancing, self-isolation, changes in food access, more intense use of social media platforms, disruption of daily habits, and more difficult access to healthcare practitioners. The lack of physical activity in addition to vitamin D deficiency related to low sun exposure or to the use of facial masks may also be connected to further bone damage related to this disease.