- Nearly everyone experiences stress at some time. Stress produces changes in the body such as increased heart rate, blood pressure, and altered immune function.
- Some amount of stress is healthy, but excessive stress, left untreated, can increase a person's risk for anxiety and illness.
- In the American Psychological Association's Stress in America Survey, major causes of stress include work, money, the economy, family responsibilities, and health concerns. Unhealthy habits uch as overeating or eating unhealthy foods can result from stress.
- The combined effect of job stress and an unhealthy lifestyle poses the highest risk for coronary heart disease (CHD) compared to either factor alone. Among those with job strain, making healthy lifestyle choices can lower the risk of CHD significantly.
- Similar studies have shown that job stress is not a significant risk for colorectal, breast, prostate, or lung cancers.
- Chronic stress is associated with adverse pregnancy outcomes, such as low birth weight. Screening and intervention strategies may help to improve outcomes.
- Researchers are looking at the effectiveness of medications, such as escitalopram, in reducing the risk of mental stress-induced myocardial ischemia (MSIMI).
- Several strategies have been shown to help reduce stress, such as exercise, practicing mindfulness-based stress reduction (meditation and yoga), acceptance and commitment therapy (ACT), and participating in a cognitive behavioral therapy (CBT) program.
- CBT has been shown to help reduce the stress associated with many chronic medical conditions, including back pain, arthritis, and tinnitus (buzzing in the ears).
- Meditation may help ease symptoms of anxiety, depression, and pain, but its role in modulating positive mood, attention, substance use, eating habits, sleep, and weight gain is less clear.
- Certain medications may help to treat specific post-traumatic stress disorder (PTSD) symptoms, such as trauma nightmares.
- Several pilot projects are underway to assess the effects of "virtual healing" using devices such as video game simulators that might augment traditional stress management therapies.
- Internet-based approaches are improving access to guided self-help psychological interventions.
Stress affects most people in some way. Acute (sudden or short-term) stress leads to rapid changes throughout the body. Almost all body systems (the heart and blood vessels, immune system, lungs, digestive system, sensory organs, and brain) gear up to meet perceived danger.
These stress responses could prove beneficial in a critical, life-or-death situation. Over time, however, repeated stressful situations put a strain on the body that may contribute to physical and psychological problems. Chronic (long-term) stress can have real health consequences and should be addressed like any other health concern.
Fortunately, research is showing that lifestyle changes and stress-reduction techniques can help people manage stress.
External and Internal Stressors
People can experience stress from external or internal factors.
- External stressors include adverse physical stimuli (such as pain or hot or cold temperatures) or stressful psychological environments (such as poor working conditions or abusive relationships).
- Internal stressors can also be physical (infections and other illnesses, inflammation) or psychological (such as intense worry about an event that may or may not occur). As far as anyone can tell, internal psychological stressors are rare or absent in most animals except humans.
Acute or Chronic Stress
Stressors can also be defined as short-term (acute) or long-term (chronic).
Acute Stress: Acute stress is the reaction to an immediate threat, commonly known as the fight or flight response, and is accompanied with the release of stress hormones. The threat can be any situation that is perceived, even subconsciously or falsely, as a danger.
Common acute stressors include:
- Noise (which can trigger a stress response even during sleep)
- High technology effects (such as playing video games or frequently ringing mobile phones)
- Imagining a threat or remembering a dangerous event
Under most circumstances, once the acute threat has passed, levels of stress hormones return to normal. This is called the relaxation response.
Chronic Stress: Frequently, modern life exposes people to long-term stressful situations. Stress, then, becomes chronic. The urge to act (to fight or flee) must therefore be controlled.
Common chronic stressors include:
- Ongoing work pressure
- Long-term relationship problems
- Persistent financial worries
Stress in America Survey
The American Psychological Association conducted its most recent Stress in America Survey in 2014. A representative sample of 3,068 adults in the general population were evaluated. The survey found that overall, Americans are experiencing somewhat less stress than 7 years earlier. However, this trend is not equally shared in the population, and higher stress levels are still reported among low-income households, parents, younger generations, and women. Money appears to be the major source of high stress levels, and has impacted about one-third of Americans from leading a healthier life. Twenty percent of individuals with financial concerns are less likely to see a doctor when they need health care. They are also more likely to engage in unhealthy habits, such as lying awake at night or oversleeping, overeating, skipping meals, or becoming sedentary in general, due to stress. Emotional support was found as an important factor in helping individuals manage their stress in more effective and healthier ways.
Specific results include:
- Most Americans report feeling moderate-to-high stress levels.
- 72% of adults report that money causes them stress at least some of the time.
- Steep health care costs and rising costs of living are a major source of money-related stress, particularly among parents and younger generations (Millennials and Gen Xers).
- Adults in lower-income households are more likely to engage in sedentary or unhealthy behavior than in higher-income households.
- Women report a higher level of stress than men, most of which is caused by money and family responsibilities.
- Other sources of stress include work, the economy, and personal health concerns.
- Lack of willpower, time, and finances are barriers to making changes to better manage stress.
- Emotional support from friends and family can significantly improve stress levels and management. However finding support proves difficult, with 21% of Americans reporting that they have no one to turn to.
The Body's Response
The best way to envision the effect of acute stress is to imagine yourself in a primitive situation, such as being chased by a bear.
The Brain's Response to Acute Stress
In response to seeing the bear, a part of the brain called the hypothalamic-pituitary-adrenal (HPA) system is activated.
Release of Steroid Hormones and the Stress Hormone Cortisol: The HPA system triggers the production and release of steroid hormones (glucocorticoids), including the primary stress hormone cortisol. Cortisol is very important in organizing systems throughout the body (including the heart, lungs, circulation, metabolism, immune systems, and skin) to deal quickly with the bear.
Release of Catecholamines: The HPA system also releases certain neurotransmitters (chemical messengers) called catecholamines, particularly those known as dopamine, norepinephrine, and epinephrine (also called adrenaline).
Catecholamines activate an area inside the brain called the amygdala, which appears to trigger an emotional response to a stressful event. In the case of the bear, this emotion is most likely fear.
Release of Neuropeptide S: The brain releases neuropeptide S, a small protein that modulates stress by decreasing sleep and increasing alertness and a sense of anxiety. This gives the person a sense of urgency to run away from the bear.
Effects on Long- and Short-Term Memory: During the stressful event, catecholamines also suppress activity in areas at the front of the brain concerned with short-term memory, concentration, inhibition, and rational thought. This sequence of mental events allows a person to react quickly, either to fight the bear or to flee from it. It also interferes with the ability to handle difficult social or intellectual tasks and behaviors during that time.
At the same time, neurotransmitters signal the hippocampus (a nearby area in the brain) to store the emotionally loaded experience in long-term memory. In primitive times, this brain action would have been essential for survival, because long-lasting memories of dangerous stimuli (such as the large bear) would be critical for avoiding such threats in the future.
Research also finds that during times of stress, nerve cells in the brain interpret chemical signals incorrectly. Instead of switching "off," these nerve cells perceive the signals as telling them to switch "on." It is as though the brain's "brakes" fail in response to stress.
Response by the Heart, Lungs, and Circulation to Acute Stress
The stress response also affects the heart, lungs, and circulation:
- As the bear comes closer, the heart rate and blood pressure increase instantaneously.
- Breathing becomes rapid, and the lungs take in more oxygen.
- The spleen discharges red and white blood cells, allowing the blood to transport more oxygen throughout the body. Blood flow may actually increase 300 to 400%, priming the muscles, lungs, and brain for added demands.
The Immune System's Response to Acute Stress
The effect of confronting the bear on the immune system is similar to mobilizing a defensive line of soldiers to potentially critical areas. The steroid hormones reduce activity in parts of the immune system, so that specific infection fighters (including important white blood cells) or other immune molecules can be repositioned. These immune-boosting troops are sent to the body's front lines where injury or infection is most likely to occur, such as the skin and the lymph nodes.
The Acute Response in the Mouth and Throat
As the bear gets closer, fluids are diverted from nonessential locations, including the mouth. This causes dryness and difficulty talking. In addition, stress can cause spasms of the throat muscles, making it difficult to swallow.
The Skin's Response to Acute Stress
The stress effect moves blood flow away from the skin to support the heart and muscle tissues. This also reduces blood loss in the event that the bear causes a wound. The physical effect is cool, clammy, sweaty skin. The scalp also tightens so that the hair seems to stand up.
Metabolic Response to Acute Stress
Stress reduces digestive activity, a body function that is not essential during short-term periods of hard physical work or crisis.
The Relaxation Response: the Resolution of Acute Stress
Once the threat has passed without any harmful outcome (for example, the bear has not wounded the human), the stress hormones return to normal. This is known as the relaxation response. In turn, the body's systems also return to normal.
Risk Factors for Stress
At some point in their lives, virtually everyone will experience stressful events or situations that overwhelm their natural coping mechanisms. Some people are simply biologically prone to stress. Many outside factors influence susceptibility as well.
Conditions Most Likely To Produce Stress-Related Health Problems: Conditions that are most likely to be associated with stress and negative physical effects include the following:
- An accumulation of persistent stressful situations, particularly those that a person cannot easily control (for example, a high-pressure job plus an unhappy relationship)
- Persistent stress after a severe acute response to a traumatic event (such as an automobile accident)
- Acute stress accompanying a serious illness, such as heart disease
Factors That Influence the Response to Stress: People respond to stress differently, depending on different factors:
- Early nurturing: People who were abused in childhood may have long-term abnormalities in the HPA system, which regulates stress.
- Personality traits: Certain people have personality traits that cause them to over-respond to stressful events. For example, those who are neurotic may get stressed more easily and turn to unhealthy behaviors such as smoking and heavy drinking as a result. Being more outgoing and aware of the world may improve a person's response to stress by lowering levels of stress-related inflammatory hormones.
- Genetic factors: Some people have genetic factors that affect stress, such as having a more or less efficient relaxation response.
- Immune regulated diseases: Certain diseases that are associated with immune abnormalities (such as rheumatoid arthritis or eczema) may weaken the response to stress.
- The length and quality of stressors: The longer the duration and the more intense the stressors, the more harmful the effects.
Individuals at Higher Risk for Stress: Studies indicate that the following people are more vulnerable than others to the effects of stress:
- Older adults: As people age, achieving a relaxation response after a stressful event becomes more difficult. Aging may simply wear out the systems in the brain that respond to stress, so that they become inefficient. The elderly, too, are very often exposed to major stressors such as medical problems, the loss of a spouse and friends, a change in a living situation, and financial worries. No one is immune to stress, however.
- Women in general and working mothers specifically: Working mothers, regardless of whether they are married or single, face higher stress levels and possibly adverse health effects, most likely because they bear a greater and more diffuse work load than men or other women. This effect has been observed in women in the U.S. and in Europe. Such stress may also have a harmful effect on their children. It is not clear, however, whether stress has the same adverse effects on women's hearts as it does on men's.
- Less educated individuals.
- Divorced or widowed individuals: Numerous studies indicate that unmarried people generally do not live as long as their married contemporaries.
- Anyone experiencing financial strain, particularly the long-term unemployed and those without health insurance.
- People who are isolated or lonely.
- People who are targets of racial or sexual discrimination.
- People who live in cities.
Children are frequent victims of stress because they are often unable to communicate their feelings accurately. They also have trouble communicating their responses to events over which they have no control. Certain physical symptoms, notably repeated abdominal pain without a known cause, may be indicators of stress in children.
Various conditions can affect a child's susceptibility to stress.
Parental Stress: Parental stress, especially in mothers, is a particularly powerful source of stress in children. Young children of mothers who are highly stressed (particularly if they are also depressed) tend to be at high risk for developing stress-related problems. This may be especially true if the mothers were stressed during both the child's infancy and early years. Stressed parents may even make their children more likely to develop asthma. Some evidence supports the old idea that stress during pregnancy can have adverse effects on the infant's mood and behavior. Older children with stressed mothers may become aggressive and anti-social. Stress-reduction techniques in parents may improve their children's behavior.
Gender Differences in Adolescent Stress: Adolescent boys and girls experience equal amounts of stress, but the source and effects may differ. Girls tend to become stressed from interpersonal situations, and stress is more likely to lead to depression in girls than in boys. For boys, however, specific events, such as changing schools or getting poor grades, appear to be the major sources of stress.
Work and Stress
Health care costs are much higher in workers who are stressed or depressed than in others who are not stressed. Nearly half of American workers describe their jobs as very stressful, making job-related stress an important and preventable health hazard. In a struggling economy, worry about job loss produces a tremendous amount of stress.
Several studies are now suggesting that job-related stress is as great a threat to health as smoking or not exercising. Stress impairs concentration, causes sleeplessness, and increases the risk for illness, back problems, accidents, and lost time from work. Work stress can lead to harassment or even violence on the job. At its most extreme, chronic stress places a burden on the heart and circulation that in some cases may be fatal.
Not all work stress is harmful. However, studies suggest the following job-related stressors may increase health risks, particularly in men:
- Having no control over decisions that affect one's responsibilities
- Unrelenting and unreasonable performance demands
- Lack of effective communication and conflict-resolution methods among workers and employers
- Lack of job security
- Night-shift work, long hours, or both
- Spending too much time away from home and family
- Wages not matching levels of responsibility
Reducing Stress on the Job: Many companies put intense pressure on their employees to behave in ways that increase tension. Yet, there are numerous effective tools and techniques available to reduce stress, and have proven beneficial for both the employee and employer. Studies show that stress management programs save in workers compensation costs, and may lower employees' blood pressure.
In general, however, few workplaces offer stress management programs, and it is usually up to the employees to find their own ways to reduce stress. Here are some suggestions:
- Seek out someone in the Human Resources department or a sympathetic manager and communicate concerns about job stress. Work with them in a non-confrontational way to improve working conditions, letting them know that productivity can be improved by reducing the pressure on employees.
- Establish or strengthen a network of friends at work and at home.
- Restructure priorities and eliminate unnecessary tasks.
- Learn to focus on positive outcomes.
- If the job is unendurable, plan and execute a career change. Send out resumes or work on getting a transfer within the company.
- If this is not possible, be sure to schedule pleasant activities and physical exercise every day during free time.
Caregivers of Family Members: Studies show that caregivers of physically or mentally disabled family members are at risk for chronic stress. Spouses who care for a disabled partner are particularly vulnerable to a range of stress-related health threats, including influenza, depression, and heart disease. Caring for a spouse who has even minor disabilities can lead to severe stress.
Specific risk factors that put caregivers at higher risk for severe stress, or stress-related illnesses, include:
- Being a wife: Some studies suggest that wives experience significantly greater stress from caregiving than husbands.
- Having a low income.
- Being African-American: African-Americans tend to be in poorer physical health, and have lower incomes, than Caucasians. They, therefore, face greater stress as caregivers to their spouses than their white counterparts.
- Living alone with a patient.
- Helping a highly dependent person.
- Having a difficult relationship with a person.
Intervention programs aimed at caregivers can help reduce stress, and help the caregiver maintain a positive attitude. Moderate-intensity exercise can also be very helpful in reducing stress and improving sleep in caregivers.
Health Professional Caregivers: Caregiving among health professionals is also a high risk factor for stress. One study found that registered nurses with low job control, high job demands, and low work-related social support experienced very dramatic health declines, both physically and emotionally.
People who are less emotionally stable or who have high anxiety levels tend to experience specific events more stressfully than others. Some doctors describe an exaggerated negative response to stress as "catastrophizing" the event (thinking of a problem as a catastrophe). However, research has found that patients with anxiety disorder do not have any differences in their actual physical response to stress (such as heart rate, blood pressure, or release of stress hormones) compared to people without anxiety.
Lacking a Social Network
The lack of an established network of family and friends predisposes a person to stress disorders and stress-related health problems, including heart disease and infections. Older people who maintain active relationships with their adult children are buffered against the adverse health effects of chronic stress-inducing situations, such as low income or lower social class. This may be because people who live alone are unable to discuss negative feelings to relieve their stress.
People who remain happy and healthy despite many life stresses typically have very good social support networks. Having a pet may help reduce medical problems that are aggravated by stress, including heart disease and high blood pressure.
In prehistoric times, the physical changes in response to stress were an essential adaptation for meeting natural threats. Even in the modern world, the stress response can be an asset for raising levels of performance during critical events, such as a sports activity, an important meeting, or in situations where there is actual danger or a crisis.
When stress becomes persistent and low-level all parts of the body's stress apparatus (the brain, heart, lungs, blood vessels, and muscles) become chronically over-activated or under-activated. Such chronic stress may produce physical or psychological damage over time. Acute stress can also be harmful in certain situations, particularly in individuals with pre-existing heart conditions.
Psychological Effects of Stress
Studies suggest that the inability to adapt to stress is associated with the onset of depression or anxiety.
Some evidence suggests that the repeated release of stress hormones produces hyperactivity in the hypothalamic-pituitary-adrenal (HPA) system, and disrupts normal levels of serotonin, the brain chemical that is critical for feelings of well-being. Some people appear to be more at risk for an overactive HPA system under stress, including those with personality traits that tend towards perfectionism. On a more obvious level, stress reduces quality of life by affecting feelings of pleasure and accomplishment. In addition, relationships are often threatened in times of stress.
The full impact of mental stress on heart disease is just coming to light, but the underlying mechanisms are not always clear. Stress can influence the activity of the heart when it activates the automatic nervous system. Such actions and others could negatively affect the heart in several ways:
- Sudden stress increases the pumping action and rate of the heart, while at the same time causing the arteries to constrict (narrow). As a result blood pressure rises.
- The emotional effects of stress alter the heart rhythms, which could pose a risk for serious arrhythmias (rhythm abnormalities) in people with existing heart rhythm disturbances.
- Stress causes certain blood cells to become stickier (possibly in preparation for potential injury).
- Stress appears to impair the clearance of fat molecules in the body.
- Stress that leads to depression appears to be associated with increased intima-medial thickness, a measure of the arteries that signifies worsening blood vessel disease.
- Stress causes the body to release inflammatory markers into the bloodstream. These markers may worsen heart disease or increase the risk of a heart attack or stroke.
- Studies have reported an association between stress and high blood pressure, which may be more pronounced in men than in women. According to some evidence, people who regularly experience sudden spikes in blood pressure (caused by mental stress) may, over time, develop injuries to the inner lining of their blood vessels.
Evidence is still needed to confirm any clear-cut relationship between stress and heart disease. However, research has linked stress to heart disease in men, particularly in work situations where they lack control. The association between stress and heart problems in women is weaker, and there is some evidence that the ways in which women cope with stress may be more heart-protective.
Studies have shown that the combined effect of job stress and an unhealthy lifestyle poses a higher risk for coronary heart disease (CHD) than either factor alone. Among those with job strain, making healthy lifestyle choices can lower the risk of CHD significantly.
A condition called stress cardiomyopathy (or Takotsubo cardiomyopathy) is widely recognized. In this disease, intense emotional or physical stress causes severe but reversible heart dysfunction. The person experiences chest pain, and electrocardiograms (EKGs) and echocardiograms indicate a heart attack, but further tests show no underlying obstructive coronary artery disease.
Psychological stress is also recognized as a possible cause of acute coronary syndrome (ACS), a collection of symptoms that indicate a heart attack or approaching heart attack. High levels of psychological stress are associated with harmful changes to the blood. Research suggests that stress has the potential to trigger ACS, particularly in patients with heart disease. Studies also suggest that the risk is greatest immediately after a stressful incident, rather than during it.
Researchers are looking at the effectiveness of medications, such as escitalopram, in reducing the risk of mental-stress induced myocardial ischemia (MSIMI), a condition characterized by reduced blood supply to the heart. More research is necessary however.
Stress Reduction and Heart Disease: Studies suggest that treatments that reduce psychological distress improve the long-term outlook in people with heart disease, including after a heart attack. Evidence indicates that stress management programs may significantly reduce the risk of heart attacks in people with heart disease. Specific stress management techniques may help some heart problems but not others. For example, acupuncture in one study helped people with heart failure but had no effect on blood pressure. Relaxation methods, on the other hand, may help people with high blood pressure.
In some people, prolonged or frequent mental stress causes an increase in blood pressure, a risk factor for stroke and heart disease.
Effect on the Immune System
Chronic stress affects the immune system in complicated ways, and may have various results.
Susceptibility to Infections: Chronic stress may have an effect on the immune system's response to infections. Several studies claim that people who are under chronic stress have low white blood cell counts and are more vulnerable to colds. Once a person catches a cold or flu, stress can make symptoms worse. People who carry the herpes virus may be more susceptible to viral activation after they are exposed to stress.
Inflammatory Response: Some evidence suggests that chronic stress triggers an over-production of certain immune factors called cytokines. Such findings may partly explain the association between chronic stress and numerous diseases, including heart disease and asthma.
A relationship between excess stress and cancer has not been proven. Evidence has shown that job stress is not a significant risk for colorectal, breast, prostate, or lung cancer. However, there may be a connection between stress and cancer survival. One study suggested that cancer patients who were separated from their spouses had lower survival rates than married cancer patients. Although stress reduction techniques have no effect on survival rates, studies show that they are very helpful in improving a cancer patient's quality of life.
The brain and intestines are closely related. They are controlled by many of the same hormones and parts of the nervous system. Some research suggests that the gut itself has features of a primitive brain. It is not surprising then that prolonged stress can disrupt the digestive system, irritating the large intestine and causing diarrhea, constipation, cramping, and bloating. Excessive production of digestive acids in the stomach may cause a painful burning.
Irritable Bowel Syndrome (IBS): IBS (or spastic colon) is strongly related to stress. With this condition, the large intestine becomes irritated, and its muscular contractions are spastic rather than smooth and wave-like. The abdomen is bloated, and the patient experiences cramping and alternating periods of constipation and diarrhea. Sleep disturbances due to stress can make irritable bowel syndrome even worse.
Peptic Ulcers: It is now well established that most peptic ulcers are caused by H. pylori bacteria or the use of nonsteroidal anti-inflammatory (NSAID) medications (such as aspirin and ibuprofen). Nevertheless, studies still suggest that stress may predispose a person with H. pylori to ulcers.
Inflammatory Bowel Disease: Although stress is not a cause of inflammatory bowel disease (Crohn disease or ulcerative colitis), there are reports of an association between stress and symptom flare-ups.
Eating and Stress
Stress can have varying effects on eating problems and weight. Many Americans report overeating, eating unhealthy foods, or skipping meals due to stress.
Weight Gain: Often stress is related to weight gain and obesity. Many people develop cravings for salt, fat, and sugar to counteract tension. As a result, they gain weight. For some people who are exposed to stress, they gain weight even with a healthy diet. In addition, the weight gained is often abdominal fat, which increases the risk of diabetes and heart problems.
The release of cortisol, a major stress hormone, appears to boost abdominal fat and may be the primary connection between stress and weight gain. Cortisol is a glucocorticoid. These hormones, along with insulin, appear to be responsible for stress-related food cravings. Evidence suggests that hormonally induced cravings for "comfort foods" may have a biological benefit for managing stress. Eating comfort foods appears to reduce the negative hormonal and behavioral changes associated with stress, which might lessen the impact of stress on an individual. Carbohydrates in particular may increase levels of tryptophan and large neutral amino acids. This leads to more production of the chemical messenger serotonin, which might improve mood and performance under stress.
There may be a "reward-based stress eating" model. In this theory, both stress and tasty, high-calorie foods cause the brain to make chemicals called endogenous opioids. These neurotransmitters help protect against the harmful effects of stress, slowing activity of a brain process called the hypothalamic-pituitary-adrenal (HPA) axis, thus weakening the stress response. Repeated stimulation of the reward pathways through stress-induced HPA stimulation, eating tasty food, or both, may lead to changes in the brain that cause compulsive overeating.
Research finds that overeating may be triggered by different stressors in men and women. Women tend to put on extra pounds when dealing with financial and work problems, as well as strained family relationships. Men gain more weight from lack of decision authority at work and difficulty in learning new skills on the job.
Eating Disorders: Chronically elevated levels of stress chemicals have been observed in people with anorexia and bulimia. Some studies, however, have not found any strong link between stress and eating disorders. More research is needed to determine whether changes in stress hormones are a cause or a result of eating disorders.
Stress can exacerbate existing diabetes by impairing the patient's ability to manage the disease effectively.
Researchers are attempting to find the relationship between pain and emotion, but the area is complicated by many factors, including the effects of different personality types, fear of pain, and stress itself. Evidence suggests that chronic pain may impair the action of neutrophils, a type of white blood cell, thereby weakening the immune response.
Muscular and Joint Pain: Stress may intensify chronic pain caused by arthritis and other conditions. Psychological distress also plays a significant role in the severity of back pain. Some studies have clearly associated job dissatisfaction and depression to back problems, although it is still unclear whether stress is a direct cause of the back pain. Research suggests that the risk of long-term disability from low back pain can be reduced through early treatment for depression and stress.
Headaches: Tension-type headaches are highly associated with stress and stressful events. Sometimes the headache does not start until long after the stressful event has ended. Additionally, stress can contribute to the development or cause headaches to occur more frequently.
Some research suggests that people who experience tension-type headaches may have some biological predisposition for translating stress into muscle contractions. Among the wide range of possible migraine triggers is emotional stress, although the headaches often erupt after the stress has eased.
The tensions of unresolved stress frequently cause insomnia, which prevents stressed people from sleeping or causes them to awaken in the middle of the night or early morning. This appears to be due to the fact that stress causes physiological arousal during non-rapid eye movement sleep.
Sexual and Reproductive Dysfunction
Sexual Function: Stress can reduce sexual desire and prevent women from achieving orgasm. The stress response can lead to sexual problems, including erectile dysfunction, in men.
Premenstrual Syndrome: Some studies indicate that the stress response in women with premenstrual syndrome may be more intense than in those without the syndrome.
Fertility: Chronic stress may affect fertility. Stress hormones have an impact on the hypothalamus, which produces reproductive hormones. This effect may lead to changes in a woman's menstrual cycle, as well as a reduction in a man's sperm count. Stress can also reduce sex drive.
Effects on Pregnancy: Old wives' tales about a pregnant woman's emotions affecting her baby may have some credence. Stress may cause physiological alterations, such as increased adrenal hormone levels or resistance in the arteries, which may interfere with normal blood flow to the placenta. Maternal stress during pregnancy has been linked to a higher risk for miscarriage, lower birth weight, and an increased incidence of premature births. Some evidence also suggests that an expectant mother's stress can even influence the way in which her baby's brain and nervous system will react to stressful events. One study found a higher rate of crying and low attention in infants of mothers who had been stressed during pregnancy. These outcomes can have far-reaching effects on a child's life.
Menopause: A drop in estrogen levels during perimenopause and menopause may be responsible for changes in mood precipitated by stress.
Memory, Concentration, and Learning
Stress affects the brain, particularly memory, but the effects vary widely depending on whether the stress is acute or chronic.
Effect of Acute Stress on Memory and Concentration: Studies indicate that the immediate effect of acute stress impairs short-term memory, particularly verbal memory. On the plus side, high levels of stress hormones during short-term stress have been associated with enhanced memory storage, improved working memory, and greater concentration on immediate events. The difference in effect may be due to how cortisol impacts glucocorticoid receptors in the hippocampus and prefrontal cortex.
Effect of Chronic Stress on Memory: If stress becomes chronic, sufferers often lose concentration at work and home, and they may become inefficient and accident-prone. In children, the physiologic responses to chronic stress can interfere with learning. Studies have connected long-term exposure to excess amounts of the stress hormone cortisol to a shrinking of the hippocampus, the brain's memory center. It is not yet known whether this shrinking is reversible.
Skin Disorders: Stress may worsen numerous skin conditions, including hives, psoriasis, acne, and rosacea, and it is one of the most common causes of eczema. Unexplained itching may also be caused by stress. Evidence suggests that experiencing the stress of a traumatic event (parental divorce or separation, or a severe disease in a family member) before age 2 increases the risk of developing eczema.
Unexplained Hair Loss (Alopecia Areata): Alopecia areata is hair loss that occurs in localized (individual) patches. The cause is unknown, but stress is suspected as a player in this condition. For example, hair loss often occurs during periods of intense stress, such as when people are in mourning.
Teeth and Gums: Stress has now been implicated in increasing the risk for periodontal disease, which can cause tooth loss and has been linked to heart disease.
People who are under chronic stress often turn to alcohol or tobacco for relief. Stress compounds the damage that these self-destructive habits cause under ordinary circumstances. Many people also resort to unhealthy eating habits, smoking, or passive activities, such as watching television when they are stressed.
Alcohol affects receptors in the brain that reduce stress. Lack of nicotine increases stress in smokers, which creates a cycle of dependency on smoking.
The cycle is self-perpetuating: a sedentary routine, an unhealthy diet, alcohol abuse, and smoking all promote heart disease. They also interfere with sleep patterns, and lead to increased rather than reduced tension levels. Drinking four or five cups of coffee, for example, can cause changes in blood pressure and stress hormone levels similar to those produced by chronic stress. Animal fats, simple sugars, and salt are known contributors to health problems.
Conditions with Similar Symptoms
The physical symptoms of anxiety disorders mirror many symptoms of stress, including:
- A fast heart rate
- Rapid, shallow breathing
- Increased muscle tension
Anxiety is an emotional disorder that is characterized by feelings of apprehension, uncertainty, fear, or panic. Unlike stress, the triggers for anxiety are not usually associated with specific stressful or threatening conditions. Some individuals with anxiety disorders have numerous physical complaints, such as headaches, gastrointestinal disturbances, dizziness, and chest pain. Severe cases of anxiety disorders are debilitating, interfering with a person's career, family, and social life.
Depression can be a disabling condition, and, like anxiety disorders, it may sometimes be linked to chronic stress. Individuals with high levels of work-related stress are more than twice as likely to experience a major depressive episode, compared with people who are under less stress. Evidence also suggests that certain people may be genetically susceptible to depression after they experience stressful life events.
Depression shares some of the symptoms of stress, including changes in appetite, sleep patterns, and concentration. Serious depression, however, is distinguished from stress by feelings of sadness, hopelessness, loss of interest in life, and, sometimes, thoughts of suicide. Acute depression is also accompanied by significant changes in the person's functioning. The person may need professional therapy to determine whether depression is caused by stress, or if it is the primary problem.
Post-Traumatic Stress Disorder Symptoms
Post-traumatic stress disorder (PTSD) is a reaction to a very traumatic event, and it is typically classified as an anxiety disorder. The event that brings on PTSD is usually outside the norm of human experience, such as intense combat or sexual assault. The patient struggles to forget the traumatic event and frequently develops emotional numbness and event-related amnesia. Often, however, there is a mental flashback, and the person re-experiences the painful circumstance in the form of dreams and disturbing thoughts and memories. These thoughts and dreams resemble or recall the trauma. Other symptoms may include a lack of pleasure in previously enjoyed activities, hopelessness, irritability, mood swings, sleep problems, inability to concentrate, and an excessive startle-response to noise.
There are several screening tools available to screen for post-traumatic stress, such as Breslau's Short Screening Scale and Primary Care PTSD Screen (PC-PTSD).
While various interventions to treat or prevent PTSD are being tested, not just one program will help all victims, and research is somewhat limited. Many experts favor a multifactorial approach to therapy that includes talk therapy (such as cognitive behavioral therapy [CBT]) and medications (such as drugs in the selective serotonin reuptake inhibitor (SSRI) family used for depression). Core symptoms of PTSD can be treated with medications. For example, prazosin is effective for treating trauma nightmares, associated with PTSD.
There is evidence that CBT is effective in treating children and adolescents with PTSD, but more research is needed.
Early intervention appears to have the most benefit.
Acceptance and commitment therapy (ACT) is another form of behavioral therapy being evaluated for treating PTSD.
On the horizon are "virtual therapies," computerized programs or simulations, to treat PTSD symptoms. This approach is being studied in military veterans suffering from PTSD.
The process of learning to control stress is life-long. Overcoming stress will not only contribute to better health, but it will also increase an individual's ability to succeed.
When to Seek Professional Help for Stress
Stress can be a factor in a variety of physical and emotional illnesses, which should be professionally treated. Many stress symptoms are mild and can be managed with over-the-counter medications (for example, aspirin, acetaminophen, or ibuprofen for tension headaches; antacids, anti-diarrhea medications, or laxatives for mild stomach distress). A physician should be consulted, however, for physical symptoms that are out of the ordinary, particularly those that get worse or wake a person up at night. A mental health professional should be consulted for unmanageable acute stress or for severe anxiety or depression. Often short-term therapy can resolve stress-related emotional problems.
The Depression Anxiety Stress Scales (DASS) and other assessment tools are available to help identify aspects of stress such as difficulty relaxing, nervous arousal and being agitated/irritable, and determine whether depression and/or anxiety are present as well. The DASS is available to the public online.
Considerations for Choosing a Stress-Reduction Strategy
When choosing specific strategies for treating stress, several factors should be considered.
- No single method is always successful: A combination of approaches is generally most effective.
- What works for one person does not necessarily work for someone else.
- Stress can be positive as well as negative. Appropriate and controllable stress provides interest and excitement, and motivates the individual to greater achievement. A lack of stress may lead to boredom and depression.
Stress may play a part in making people vulnerable to illness. A physician or psychologist should be consulted if there are any indications of accompanying medical or psychological conditions, such as heart symptoms, significant pain, anxiety, or depression.
Overcoming Obstacles to Treatment
People often succeed in relieving stress for the short term. However, they go back to their previous stressful thoughts and behaviors because of outside pressure, long-held beliefs, or old habits. The following are some obstacles to managing stress:
- The fight or flight urge: The very idea of relaxation can feel threatening, because it is perceived as letting down one's guard. For example, an over-demanding boss may put a subordinate into a psychological state of fighting-readiness, even though there is no safe opportunity for the subordinate to fight back or express anger. Stress builds up, but the worker has the illusion, even subconsciously, that the stress itself is providing safety or preparedness. For this reason, the employee does nothing to correct the condition.
- Many people are afraid of being perceived as selfish if they engage in stress-reducing activities that benefit only themselves. The truth is that self-sacrifice (not intended for reducing one's stress) may be inappropriate and even damaging, if the person making the sacrifice is unhappy, angry, or physically unwell.
- Some people believe that certain emotional responses to stress, such as anger, are natural and unchangeable features of their personality. Research has shown, however, that with cognitive behavioral therapy, individuals can be taught to change their emotional reactions to stressful events.
- In addition, many Americans report that lack of willpower, time, finances, and stress itself are barriers to better stress management.
Reducing stress and staying relaxed clears the mind so it can begin the appropriate actions to get rid of the stress-related conditions.
Stress Reduction and Its Effects on Health
Although treating stress cannot cure medical problems, stress management can be a very important part of medical treatment. Specific stress reduction approaches may benefit different medical problems. For example, acupuncture can help reduce harmful heart muscle actions in people with heart failure, but it has no effect on blood pressure. Relaxation methods, on the other hand, may help people with high blood pressure. Stress reduction may improve well-being and quality of life in many people who are experiencing stress because of severe or chronic medical conditions.
Important Note: Never use stress reduction techniques as the only treatment, or in place of proven treatments, for any medical condition.
A healthy lifestyle is an essential companion to any stress-reduction program. People can enhance their general health and stress resistance by getting regular exercise, eating a diet rich in a variety of whole grains, vegetables, and fruits, and avoiding excessive alcohol, caffeine, and tobacco.
Exercise in combination with stress management techniques is extremely important for many reasons:
- Exercise is an effective distraction from stressful events.
- Exercise may directly blunt the harmful effects of stress on blood pressure and the heart (exercise protects the heart).
Vary the exercise program, combining aerobic exercise with strength training. Start slowly. Strenuous exercise in people who are not used to it can be very dangerous. In addition, half of all people who begin a vigorous training program drop out within a year. Discuss any exercise program with a health care provider before starting. The key is to find activities that are exciting, challenging, and satisfying. The following are some suggestions:
- Aerobics classes at a gym
- Brisk walking (even short walks can relieve bouts of stress)
- Swimming (an ideal exercise for many stressed people, including pregnant women, people with musculoskeletal problems, and those who have exercise-induced asthma)
- Yoga or Tai chi (these techniques combine many of the relaxation benefits of breathing, muscle relaxation, and meditation while toning and stretching the muscles)
As in other areas of stress management, making a plan and executing it successfully provides feelings of mastery and control, which are very beneficial in and of themselves. Start slowly. Just 10 minutes of exercise three times a week can build a good base for novices. Gradually build up the length of these sessions to 30 minutes or more.
Cognitive-behavioral therapy (CBT) is among the most effective ways of reducing stress, whether the source of stress is chronic pain or a chronic disease. CBT may be more helpful than support groups for improving well-being and quality-of-life. It aims to alter behavior, and change thoughts, feelings, and beliefs.
A typical CBT approach includes identifying sources of stress, restructuring priorities, changing one's response to stress, and finding methods for managing and reducing stress.
Identifying Sources of Stress: One key component in most CBT approaches is keeping a diary to record daily events and activities. The first step is to note activities that put a strain on energy and time, trigger anger or anxiety, or precipitate a negative physical response (such as a sour stomach or headache). Also note positive experiences, such as those that are mentally or physically refreshing or that produce a sense of accomplishment.
After a week or 2, try to identify 2 or 3 events or activities that have been significantly upsetting or overwhelming.
Questioning the Sources of Stress: Individuals should then ask themselves the following questions:
- Do these stressful activities meet my goals or someone else's?
- Have I taken on tasks that I can reasonably accomplish?
- Which tasks are under my control and which ones aren't?
Restructuring Priorities: Adding Stress Reducing Activities: The next step is to attempt to shift the balance from stress-producing to stress-reducing activities. Eliminating stress entirely is rarely possible, but there are many ways to reduce its impact.
Consider as many relief options as possible. Examples include:
- Listen to music. Music is an effective stress reducer in both healthy individuals and people with health problems. Research finds that listening to soothing music can decrease blood pressure, heart rate, and anxiety levels in heart patients.
- Take long weekends or vacations.
- If the source of stress is in the home, plan times away, even if only for an hour or two a week.
- Replace unnecessary time-consuming chores with pleasurable or interesting activities.
- Make time for recreation. This is as essential as paying bills or shopping for groceries.
- Own a pet. Research finds that pet owners have a lower blood pressure increase in response to stress than people who do not own pets.
Discuss Feelings: The concept of communication and letting your feelings out has been so excessively promoted and parodied that it has nearly lost its value as good psychological advice. Nevertheless, feelings of anger or frustration that are not expressed in an acceptable way may lead to hostility, a sense of helplessness, and depression.
Expressing feelings does not mean venting frustration. In fact, anger may cause a spike in blood pressure in some people. Some therapists strongly recommend just talking, rather than venting anger.
The primary goal is to explain and assert one's needs to a trusted individual in as positive a way as possible. Direct communication may not even be necessary. Writing in a journal, writing a poem, or composing a letter that is never mailed may be sufficient.
Expressing one's feelings solves only half of the communication puzzle. Learning to listen, empathize, and respond to others with understanding is just as important for maintaining the strong relationships necessary for emotional fulfillment and reduced stress.
Keep Perspective and Look for the Positive: Reversing negative ideas and learning to focus on positive outcomes helps reduce tension and achieve goals. The following steps, using an example of a person who is alarmed at the prospect of giving a speech, may be useful:
- First, identify the worst possible outcomes (forgetting the speech, stumbling over words, humiliation, and audience contempt).
- Rate the likelihood of these bad outcomes happening (probably very low, or the speaker would not have been selected in the first place).
- Envision a favorable result (a well-rounded, articulate presentation with rewarding applause).
- Develop a specific plan to achieve the positive outcome such as preparing in front of a mirror, using a video camera or tape recorder, or doing relaxation exercises.
- Try to recall previous situations that initially seemed negative but ended well.
Use Humor: Research has shown that humor is a very effective mechanism for coping with acute stress. Keeping a sense of humor during difficult situations is a common recommendation of stress management experts. Laughter not only releases the tension of pent-up feelings and helps a person maintain perspective, but it also appears to have actual physical effects that reduce stress hormone levels. It is not uncommon for people to laugh intensely during tragic events, such as the death of a loved one, because this laughter helps them endure the emotional pain of the experience.
Acceptance and Commitment Therapy (ACT)
ACT is another type of behavioral analysis and therapy used for a range of mental health issues, including stress. It employs acceptance and mindfulness strategies to help individuals cope with stress. Rather than try to change difficult thoughts and feelings and eliminate stress, as CBT does, ACT aims to help people adopt acceptance, mindfulness, cognitive witnessing, values, and committed action. The practice may help to alter the experience of stress. ACT is based on six core practices:
- Acceptance of odd or uncomfortable thoughts, feelings, and sensations
- Observing one's own uncomfortable thoughts without automatically taking them literally or attaching too much significance to them
- Deciding to give attention to the present events rather than automatically focusing on the past or future
- A sense of self and ongoing awareness
- Identifying values that are personally important
- Commitment to action for achieving the personal values
ACT training can be delivered in one on one or group sessions, workshops, or self-help tools.
Relaxation and Other Alternative Techniques
Relaxation Method: Because stress is here to stay, everyone needs to develop methods to promote the relaxation response, the natural unwinding of the stress response. Relaxation lowers blood pressure, respiration, and pulse rate, releases muscle tension, and eases emotional strain. This response is highly individualized, but there are certain approaches that seem to work for most people. Meditation during the run-up to a stressful event can reduce the stress response without impairing alertness, concentration or memory.
Combinations of these techniques probably work best. No one should expect these approaches to completely relieve their stress, but if they are done regularly, these programs can be very effective. In a recent review, it was shown that mindfulness based stress reduction (MBSR) techniques are effective stress reliever, lowering stress in healthy people. Techniques include yoga and meditation. Significant reductions in stress levels were seen in participants compared to those not engaging in any treatment. Outcomes were assessed using the Mindfulness Attention Awareness Scale (MAAS).
Acupuncture: Some evidence suggests that acupuncture might improve some of the physical factors associated with both stress and health problems. For example, acupuncture may improve stress-related heart muscle activity in heart failure patients, which could provide an important benefit to these patients. However, acupuncture has no effect on stress-related blood pressure or heart rate.
Hypnosis: Hypnosis may benefit some people with severe stress. In one study of people with irritable bowel syndrome (IBS), stress reduction from hypnosis led to improvements in many bowel symptoms.
Deep Breathing Exercises. During stress, breathing becomes shallow and rapid. Taking a deep breath is an automatic and effective technique for winding down. Deep breathing exercises consciously intensify this natural physiologic reaction and can be very useful during a stressful situation, or for maintaining a relaxed state during the day.
Muscle Relaxation. Muscle relaxation techniques, often combined with deep breathing, are simple to learn and very useful for getting to sleep. In the beginning it is useful to have a friend or partner check for tension by lifting an arm and dropping it. The arm should fall freely. Practice makes the exercise much more effective and produces relaxation much more rapidly. Small studies have reported beneficial effects on blood pressure in patients with high blood pressure who use this technique.
Meditation. Meditation, used for many years in Eastern cultures, is now widely accepted in this country as a relaxation technique. The goal of all meditative procedures, both religious and therapeutic, is to quiet the mind (essentially, to relax thought). Small studies have suggested that regular meditation can benefit the heart and help reduce blood pressure. Better research is needed, however, to confirm such claims.
Some experts recommend meditating for no longer than 20 minutes in the morning after waking up and then again in the early evening before dinner. Even meditating just once a day is helpful.
New practitioners should understand that it can be difficult to quiet the mind, and should not be discouraged by a lack of immediate results.
Several techniques are available. A few are discussed here.
The only potential risks from meditating are in people with psychosis, in whom meditating may trigger a psychotic event.
Mindfulness Meditation. Mindfulness is a common practice that focuses on breathing. It employs the basic technique used in other forms of meditation.
Transcendental Meditation (TM). TM uses a mantra (a word that has a specific chanting sound but no meaning). The person meditating repeats the word silently, letting thoughts come and go.
Mini-Meditation. The method involves heightening awareness of the immediate surrounding environment. Choose a routine activity, for example:
Biofeedback. Biofeedback is a technique that measures bodily functions, such as breathing, heart rate, blood pressure, skin temperature, and muscle tension. By watching these measurements, individuals can learn how to alter these functions by relaxing or holding pleasant images in their mind.
Massage Therapy. Massage therapy may decrease cortisol levels, and some research suggests a possible role of physical touch in managing stress.
Many massage techniques are available, such as the following:
Swedish massage is the standard massage technique. It uses long smooth strokes, and kneading and tapping of the muscles.
Shiatsu applies intense pressure to the same points targeted in acupuncture. It can be painful, but people report deep relaxation afterward.
Reflexology manipulates acupuncture points in the hands and feet.
Herbal and Natural Remedies
Some people who experience chronic stress try herbal or natural remedies. Although many benefits are claimed, few (if any) have been proven. In addition, just as with standard drugs, so-called natural remedies can cause health problems, which can sometimes be serious. Similarly, homeopathic remedies have not shown to be effective treatments for anxiety or stress.
Aromatherapy: The smell of lavender has long been associated with a calming effect. In addition, several other aromatherapies are now used for relaxation. Use caution, however, as some of the exotic plant extracts in these formulas have been associated with a wide range of skin allergies.
Valerian: Valerian is an herb that has sedative qualities, and it may reduce stress and its associated physical effects. This herb is on the FDA's list of generally safe products. However, the herb's effects could be dangerously increased if it is used with standard sedatives. Side effects include vivid dreams. High doses of valerian can cause blurred vision, excitability, and changes in heart rhythm. Other interactions and long-term side effects are unknown.
Generally, manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like drugs, however, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been numerous reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.
Special Warning on Kava: Kava has been commonly used to reduce anxiety and stress. It is now highly associated with liver injury and even liver failure in a few cases. Experts now strongly warn against its use.
People seeking relief from stress should be wary of any product that promises a quick cure, or that requires the purchase of expensive treatments. These treatments may be useless and sometimes even dangerous.
- www.nimh.nih.gov -- National Institute of Mental Health
- www.nami.org -- National Alliance for the Mentally Ill
- www.nmha.org -- Mental Health America (formerly the National Mental Health Association)
- www.amtamassage.org -- American Massage Therapy Association
- www.healthyminds.org -- The American Psychiatric Association
- www.apa.org -- The American Psychological Association
- www.naswdc.org -- The National Association of Social Workers
- www.aacap.org -- American Academy of Child and Adolescent Psychiatry
- www.stress.org -- The American Institute of Stress
- www2.psy.unsw.edu.au/groups/dass -- Depression Anxiety Stress Scale (DASS)
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Reviewed By: Reviewed by: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team. Editorial update: 04/21/2015.