Stressed out? Learn how the body responds to stress--and healthy ways to cope.

• Position: HEADS UP: HEAL NEWS ABOUT AND YOUR BODY

Think of a time you were stressed. You may remember your heart racing, palms sweating, shoulders tensing up.

These reactions are part of the body's natural stress response. When the brain perceives a situation to be threatening, it triggers a surge of hormones that prepare the body for the challenge.

Known as "fight or flight," the stress response evolved to help us survive. But it is also triggered by events that aren't life-threatening. This can include academic and relationship pressures, or even stress from being over-connected to technology and social media. Some stress is helpful, like keeping you energized to study for a test. But constant stress can take a toll on a person's emotions and body, which can lead to serious health problems.

Your Body Under Pressure

BRAIN: The body's stress response is triggered when the brain's hypothalamus (1) sends a signal to the pituitary gland, located at the base of the brain (2). This gland then signals the adrenal glands (located above the kidneys) to release stress hormones. These hormones change how organs and systems act to prepare the body to fight or take flight.

HEART: Heart rate and blood pressure increase so that blood travels through the body faster. This helps deliver oxygen to power muscles.

LUNGS: Breathing rate increases to deliver more oxygen throughout the body to power muscles and tissues.

MUSCLES: Muscles tense up to prepare the body for action.

LIVER: The liver causes more glucose (blood sugar) to be released into the bloodstream. This powers cells in the body.

STOMACH/ INTESTINES: Digestion decreases. This redirects energy that would be used to break down food to power other parts of the body.

SWEAT GLANDS: Stress-triggered sweat is chemically different from sweat that cools the body. Stress sweat interacts with bacteria on the skin to cause body odor. Researchers aren't exactly sure why we sweat when stressed.

Fast Fact: Adrenaline, L norepinephrine, and Cortisol are the body's major stress hormones.

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Chronic Stress

Ongoing, or chronic, stress does not allow the body's stress hormones to return to normal levels. This can lead to health problems. Chronic stress can:

* Increase the risk of getting sick because stress can weaken your immune system

* Cause sleep problems because of the energy surge brought on by stress hormones

* Lead to injuries or migraine headaches from constant...