CPT1B deficiency is a rare genetic disorder that affects the body's ability to break down certain fats for energy. This condition is caused by mutations in the CPT1B gene, which is essential for the transport of long-chain fatty acids into the mitochondria, where they are converted into energy. Individuals with this deficiency may experience symptoms such as muscle pain, weakness, and fatigue, especially during prolonged exercise or fasting. Diagnosis typically involves blood tests and genetic testing to confirm the presence of CPT1B mutations. Management of the condition often includes dietary modifications to reduce fat intake and prevent episodes of metabolic crisis. Regular monitoring and support from healthcare professionals are crucial for maintaining health and preventing complications.