The symptoms of high or low Cortisol can vary, and it's important to consult with a healthcare professional for an accurate diagnosis. Symptoms of high Cortisol can include weight gain, especially in the abdomen, muscle weakness, thinning skin, mood swings, sleep disturbances, high blood pressure, and impaired immune function. On the other hand, symptoms of low Cortisol can include fatigue, weight loss, dizziness, low blood pressure, salt cravings, and mood changes. Diagnostic tests, such as Cortisol blood tests, are typically used to assess Cortisol levels and confirm the presence of imbalances.