The human body responds to stress with a powerful fight-or-flight reaction. Hormone surge through the body, causing the heart to pump faster and sending extra supplies of energy into the bloodstream. For much of human history, this emergency response system was useful: It enabled people to survive immediate physical threats, like an attack from a wild animal. But today, the stress in most people's lives comes from the more psychological and seemingly endless pressures of modern life. Daily challenges like a long commute or a difficult boss can turn on the stress hormones -- and because these conditions don't go away, the hormones don't shut off. Instead of helping you survive, this kind of stress response can actually make you sick.
Chronic stress can harm the body in several ways. The stress hormone cortisol, for instance, has been linked to an increase in fat around organs, known as visceral fat. The accumulation of visceral fat is dangerous, since these fat cells actively secrete hormones that can disrupt the functioning of the liver, pancreas and brain, causing problems such as insulin resistance, inflammation and metabolic syndrome. Chronic exposure to other stress hormones can also weaken the immune system and even change the structure of chromosomes.
How Stress Affects the Brain
Recent research suggests that chronic stress takes a toll on the brain, too. Studies on mice show that stress-related hormones alter physical structures in the brain in ways that could affect memory, learning and mood. Some of these changes involve dendrites -- tiny branch-like structures on nerve cells that send and receive signals. Several studies have shown that stress hormones can shrink dendrites and, as a result, information doesn't get relayed across nerve cells. When the cell damage occurs in a part of the brain called the hippocampus, it can impact memory and learning.
If stress makes you feel anxious, damage to dendrites might be part of the cause. A 2011 study found that rats whose dendrites had eroded due to stress had higher levels of anxiety. More research is needed to determine the exact effect of stress hormones on people's brains, but one study of adults with post-traumatic stress disorder suggests that the stress hormone cortisol may actually shrink the size of the hippocampus. Researchers are still trying to determine if this is because of the hormone's toxic effect on neurons or if there is a genetic component -- or if both are involved.
Another part of the brain that seems to be affected by stress is the amygdala -- the part of the brain that regulates fear and other emotions. A 2003 study found that in mice under stress, the amygdala grew larger while the dendrites in the hippocampus shrank. Researchers believe that together, these two effects may cause an increase in anxiety. They think that as the amygdala grows in size, you may experience more anxiety and fear. (The amygdala is known to become bigger and more active in people who are depressed). But because the hippocampus cells involved in memory are shrinking and not transmitting information effectively, you can't connect the feelings of fear to memories of real events. You're left with a lot of generalized anxiety.
Tips On Coping With Stress
If this news about stress and the brain is giving you a headache -- or stressing you out in other ways -- relax. The good news is that you can learn healthy ways to cope with stress that will protect your brain -- and the rest of your body -- from stress's negative effects.
Not everyone is equally vulnerable to stress. Genetics play a role in how a person's body reacts. Your past experiences can affect your response, too. If you lived through a lot of stressful situations growing up, you may be more sensitive to stress as an adult. Try to notice your own reactions to stress. Do you stay calm when pressures mount, or can you feel your pulse increase just thinking about a stressful situation? Once you become aware of what sets off your body's fight or flight response, you can use these tips to try to change your response to stress.
1. Resolve the stressful situation if you can. You may not have much control over many of the sources of stress in your life, but if there is a something you can do to resolve a stressful situation, do it! Talk to friends about what you can do to change a bad situation, and consider getting help from a conflict resolution expert if necessary.
2. Spend time with loved ones and cultivate healthy friendships. Research shows that a good social support network has definite mental health benefits. It can keep you from feeling lonely, isolated or inadequate and if you feel good about yourself, you can deal with stress better. Friends and loved ones can be a good source of advice and suggest new ways of handling problems. But they can also be an excellent distraction from what's bothering you. If your network of friends is small, think about volunteering, joining an outdoor activities group or trying an online meet-up group to make new friends.
3. Do an activity you like. Part of being stressed out is feeling that you never have enough time, so adding more activities to your schedule might seem like the last thing you need. But if you make even a little bit of time for an activity you really enjoy, the payoff can be huge: You feel calmer and happier and can deal with work and other demands better. Whether it's playing music, doing a craft, or working on your car, do something that absorbs and relaxes you.
4. Try relaxation techniques. Meditation, yoga, and tai chi can help slow your breathing and heart rate and focus your mind inward, away from whatever is causing you stress.
5. Exercise regularly. Whether it's walking outside with a friend or taking an exercise class at the gym, getting active can help you relax and help turn off your body's stress response.
6. Get plenty of sleep. When you're well-rested, you can approach stressful situations more calmly.
7. Eat a healthy diet. Stress is tough enough on your body, so help it out by feeding it fresh fruits and vegetables and low-fat protein.
8. Appreciate what's good in your life. It sounds corny, but focusing your thoughts on positive parts of your life instead of the stress-ridden areas can be good for your physical health. Research shows that positive emotions helped people recover their normal heart rate more quickly after it was raised during exertion.
9. Laugh! Researchers are still investigating the precise effects of laughter on stress hormones, but some findings suggest that it has a stress-relief effect on heart rate, respiratory rate and muscle tension. Your own research has probably convinced you that laughing makes you feel better.
10. Seek professional counseling if necessary. Extreme chronic stress is no laughing matter. Enlist the help of a professional if you think you are at risk for serious health effects.
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