Narrative review on low energy availability in female athletes and its endocrine and skeletal effects

The metabolic and physiological risks of the Female Athlete Triad and Relative Energy Deficiency in Sport (RED-S) remain widely under-recognized in athletic populations. Low Energy Availability (LEA), often driven by disordered eating (DE) and eating disorders (EDs), serves as the primary driver of multi-systemic impairments. This narrative review synthesizes evidence from 151 studies identified via the Scopus database. The selection process involved a careful screening of 1,589 records, focusing on the interrelationships between energy availability, disordered eating, menstrual function, and bone mineral density across various female athletic populations. The synthesis confirms that LEA leads to profound endocrine disruptions, in which weight stability often serves as a deceptive metabolic mask for underlying impairments. A significant correlation exists between disordered eating behaviors and the onset of LEA, creating a cycle that compromises hormonal integrity. Menstrual dysfunction serves as a vital clinical barometer; the resulting hypoestrogenism disrupts bone remodeling, leading to site-specific skeletal vulnerability—particularly in the lumbar spine. Furthermore, psychobehavioral factors, such as Body Image Overestimation, were identified as potent predictors of energy deficiency. Protecting the female athlete requires a proactive, multidisciplinary framework involving medical professionals, coaches, and families. Effective management must prioritize restoring energy balance to normalize menstrual function and safeguard long-term skeletal health. Future research should focus on targeted nutritional strategies and screening tools to detect early signs of LEA and disordered eating.