The normal cortisol value for both adults and children is 5 to 23 micrograms per deciliter in the morning or 3 to 16 micrograms per deciliter in the afternoon, according to WebMD. The normal cortisol value for a newborn at any time is 2 to 11 micrograms per deciliter.
High levels of cortisol sometimes indicate some cancer types or Cushing’s syndrome, a disorder of the adrenal system, notes WebMD. Obesity, hyperthyroidism, depression, and liver or kidney diseases also cause elevated levels of cortisol. Other causes of higher-than-normal cortisol levels include sepsis, which is a whole-body infection; injury; illness; and recent surgery. Pituitary or adrenal gland problems, tuberculosis and Addison’s disease often cause low levels of cortisol.