When I'm under a lot of stress I have two recurring dreams: either I'm driving in a car that I suddenly can't control (usually on crazy roads that climb high and suddenly fall away) or I'm in my house watching a tornado bear down on me. Both, I think, are easy enough to decipher and when I have them I know that it's time to take things down a notch and address whatever is causing my stress levels to rise.

Nightmares can be caused by stress, but also can be indicators of certain health issues. Common triggers of bad dreams include:

• stress and anxiety (as mentioned above)
• major life events
• illness and fever
• excessive use of alcohol or withdrawal from alcohol
• breathing disorders, including asthma and sleep apnea
• sleep disorders
• eating just before bedtime
• drug reactions

Nightmares themselves can cause anxiety and unease, so if you're suffering from recurring bad dreams and haven't pinpointed a cause, it may be worth mentioning to your doctor.

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