Stress is how your brain and body respond to a challenge or demand. When you are stressed, your body releases certain hormones. Hormones are chemicals that travel in your bloodstream and control how different parts of your body work. The hormones that are released when you are stressed make you alert and ready to act. They can raise your blood pressure, heart rate, and blood glucose (blood sugar) levels. This response is sometimes called a "fight or flight" response.

Everyone gets stressed from time to time. There are different types of stress. It can be short-term or long-term. It can be caused by something that happens once or something that keeps happening.

Not all stress is bad. In fact, it can help you survive in a dangerous situation. For example, one kind of stress is the jolt you may feel when a car pulls out in front of you while you are driving. This jolt of hormones helps you quickly hit the brakes to avoid an accident. A little short-term stress can sometimes be helpful. For example, the stress of having a deadline for school or your job may push you to get your work done on time. Once you finish it, that stress goes away.

But stress that lasts a long time can harm your health.

Long-term stress, or chronic stress, lasts for weeks, months, or longer. As you go about your life, your body is acting as if you're being threatened.

Causes of long-term stress include:

• Routine stress from the demands of work, school, family needs, money problems, and other daily pressures that don't stop.
• Stress from sudden, difficult changes in your life, such as divorce, illness, losing your job, or other unhappy life events that often have a long impact.
• Traumatic stress, which may happen when you're in danger of serious harm or death. Examples include being in a bad accident, a war, a flood, earthquake, or other frightening event. This type of stress can cause a long-lasting problem called post-traumatic stress disorder (PTSD).

People respond to stress in different ways. If you're stressed for a long time you may notice that you are:

• Getting sick more often than usual because stress weakens your body's ability to fight germs
• Having stomach problems or trouble digesting food
• Having trouble sleeping
• Having headaches
• Feeling sad, angry, or easily upset

When stress keeps going, your body acts as if you're always in danger. That's a lot of strain that may play a part in developing serious health problems, including:

• Depression
• Anxiety
• Heart disease
• High blood pressure
• Diabetes

It's possible to get used to the symptoms of stress and not even realize there's a problem. So when there's a lot of stress in your life, it's important to pay attention to how it affects you so you can do something about it.

Simple things that improve your mental health may be helpful in managing long-term stress, such as:

• Get regular exercise. A 30-minute daily walk can help you feel better and help keep your immune system strong, so you don't get sick.
• Try relaxing activities. You could look for an app or wellness program that uses breathing, meditation, or muscle relaxation exercises.
• Get enough sleep every night.
• Avoid too much caffeine.
• Decide what you need to do now and what can wait. And focus on what you got done each day, not on what you weren't able to do.
• Ask your family or friends for support.

Get help if you're having severe symptoms for 2 weeks or more, including:

• Trouble sleeping
• Changes in your eating that cause unwanted changes in your weight
• Troubles getting out of bed because of your mood
• Difficulty focusing your thoughts
• Losing interest in things you usually enjoy
• Not being able to do your usual daily activities

Always get help right away if stress is causing you to:

• Have thoughts of suicide
• Feel you can't cope
• Use drugs or alcohol more often than usual

Your health care provider may refer you to a mental health professional such as a psychologist or social worker.

NIH: National Institute of Mental Health