Cortisol is the body’s main stress hormone and plays an integral role in your body’s fight or flight response during a time of crisis. Unfortunately, modern life can be stressful with increasing pressures on trying to balance home and work demands. Lifestyle factors such as poor sleep patterns, a stressful job or difficult personal situation can increase the amount of stress placed on the body and lead to an increase in cortisol. This is important as prolonged stress can prevent cortisol responding in the normal way, and high cortisol can lead to fatigue, anxiety, weight gain and frequent illness.