The Role of CRH in Negative Health Effects of Stress

Good Stress, Bad Stress

The Role of CRH in Negative Health Effects of Stress

Feeling stressed can feel perfectly normal, especially during exam time. You might notice that sometimes being stressed-out motivates you to focus on your work, yet at other times, you feel incredibly overwhelmed and can’t concentrate on anything.

While stress affects everyone in different ways, there are two major types of stress: stress that’s beneficial and motivating — good stress — and stress that causes anxiety and even health problems — bad stress.

Here’s more on the benefits and side effects of stress and how to tell if you’re experiencing too much stress.

Benefit of Stress

According to experts, stress is a burst of energy that basically advises you on what to do. In small doses, stress has many advantages. For instance, stress can help you meet daily challenges and motivates you to reach your goals. In fact, stress can help you accomplish tasks more efficiently. It can even boost memory.

Stress is also a vital warning system, producing the fight-or-flight response. When the brain perceives some kind of stress, it starts flooding the body with chemicals epinephrine, norepinephrine and cortisol.

This creates a variety of reactions such as an increase in blood pressure and heart rate.

Plus, the senses suddenly have a laser- focus so you can avoid physically stressful situations — such as jumping away from a moving car — and be safe.

In addition, there are various health benefits with a little bit of stress. Researchers believe that some stress can help to fortify the immune system.

For instance, stress can improve how your heart works and protect your body from infection.

In one study, individuals who experienced moderate levels of stress before surgery were able to recover faster than individuals who had low or high levels.

Side Effects of Stress

Stress is key for survival, but too much stress can be detrimental. Emotional stress that stays around for weeks or months can weaken the immune system and cause high blood pressure, fatigue, depression, anxiety and even heart disease. In particular, too much epinephrine can be harmful to your heart. It can change the arteries and how their cells are able to regenerate.

Signals of Too Much Stress

It may be tough to tell when you’re experiencing good or bad stress, but there are important ways that your body lets you know that you’re struggling with too much stress. Watch out for the following warning signs:

• Inability to concentrate or complete tasks• Get sick more often with colds • Body aches• Other illnesses autoimmune diseases flare up• Headaches• Irritability • Trouble falling sleeping or staying awake• Changes in appetite

• More angry or anxious than usual

What You Can Do

Stress is an inevitable part of life, but you can improve the way you respond to stress and avoid or change some of the situations that create negative stress. Check out our article in managing stress for more tips.


Beware High Levels of Cortisol, the Stress Hormone

The Role of CRH in Negative Health Effects of Stress

  • Anxiety
  • Emotional Health
  • Stress

Women. Wisdom. Wellness. Feb 5, 2017

We’ve all felt that surge of energy as we confront something threatening or startling. A barely avoided car accident. A call that your child has been hurt. The pressure to meet a deadline.

As your body perceives stress, your adrenal glands make and release the hormone cortisol into your bloodstream. Often called the “stress hormone,” cortisol causes an increase in your heart rate and blood pressure. It’s your natural “flight or fight” response that has kept humans alive for thousands of years.

Normal levels of cortisol also are released when you wake up in the morning or exercise. These levels can help regulate your blood pressure and blood sugar levels and even strengthen your heart muscle. In small doses, the hormone can heighten memory, increase your immune system and lower sensitivity to pain.

The danger of a fast-paced culture, however, is that many of us are constantly in high-stress mode. If your body experiences chronic stress, you may begin to feel unpleasant and even dangerous effects, such as:

  • Fatigue
  • Irritability
  • Headaches
  • Intestinal problems, such as constipation, bloating or diarrhea
  • Anxiety or depression
  • Weight gain
  • Increased blood pressure
  • Low libido, erectile dysfunction or problems with regular ovulation or menstrual periods
  • Difficulty recovering from exercise
  • Poor sleep

How Cortisol Works

When the adrenal glands release cortisol into your bloodstream, the hormone triggers a flood of glucose that supplies an immediate energy source to your large muscles. It also inhibits insulin production so the glucose won’t be stored but will be available for immediate use.

Cortisol narrows the arteries, while another hormone, epinephrine, increases your heart rate. Working together, they force your blood to pump harder and faster as you confront and resolve the immediate threat.

If your entire life is high-stress and always in high gear, your body may constantly pump out cortisol.

Hormone levels return to normal as you swerve to miss an oncoming car, find out that your child has only a few scrapes or meet the deadline for your presentation.

Why Too Much of a Good Thing is Bad for You

If your entire life is high-stress and always in high gear, your body may constantly pump out cortisol. This has several negative effects.

  1. Increased blood sugar levels. Insulin typically helps the cells convert glucose to energy. As your pancreas struggles to keep up with the high demand for insulin, glucose levels in your blood remain high and your cells don’t get the sugar they need to perform at their best.
  2. Weight gain. As your cells are crying out for energy, your body may send signals to the brain that you are hungry and need to eat. Studies have demonstrated a direct association between cortisol levels and calorie intake in populations of women. False hunger signals can lead you to crave high-calorie foods, overeat and thus gain weight. Unused glucose in the blood is eventually stored as body fat.
  3. Suppressed immune system. Cortisol’s positive action to reduce inflammation in the body can turn against you if your levels are too high for too long. The elevated levels may actually suppress your immune system. You could be more susceptible to colds and contagious illnesses. Your risk of cancer and autoimmune diseases increases and you may develop food allergies.
  4. Digestive problems. When your body reacts to a threat, it shuts down other less critical functions, such as digestion. If the high-stress level is constant, your digestive tract can’t digest or absorb food well. It’s no coincidence that ulcers occur during stressful times and people with colitis or irritable bowel syndrome report better symptom control when they get their stress under control.
  5. Heart disease. Constricted arteries and high blood pressure can lead to blood vessel damage and plaque buildup in your arteries. They could be setting the stage for a heart attack or stroke.

How to Take Action

See your doctor if you are having symptoms of chronic stress. There’s a saliva test that can measure the amount of cortisol in your system, or your doctor may have other ideas about what’s causing your symptoms.

Be aware of your own stress levels and takes steps to manage your stress. Simple practices such as getting enough sleep, exercising, meditating, deep breathing techniques and scheduling leisure activities are a good start.

Source: Today’s Dietitian; American Osteopathic Association; VeryWell

Small Steps: Don’t Isolate Yourself

Whether you’re feeling grief, sadness or depression, make an effort to be with other people, do fun activities and express your feelings to someone you trust.


The Effects of Stress on the Body

The Role of CRH in Negative Health Effects of Stress

Stress is the body’s reaction to anything the ordinary.  This is directly tied to our survival instincts, otherwise known as the fight-or-flight response. 

When a person encounters a stressor (an uncommon stimulus that causes stress), the stress response is triggered. 

Several changes instantly happen within multiple bodily systems during a stress response.  Knowing these changes can be incredibly helpful when trying to deal with stress. 


Stress hormones are released immediately after a person confronts a stressor. 

Cortisol, the primary stress hormone, increases sugars in the blood stream while reducing bodily functions that aren’t essential in a fight-or-flight situation. 

Adrenaline is also released during stress responses.  Adrenaline is well-known for boosting several bodily functions; some of which are listed below. 

You may recognize some of these short-term effects of stress: 

  • Headache
  • Muscle Tension/Pain – The muscle tension brought on by stress is a common cause of tension headaches.
  • Chest Pain
  • Racing Heartbeat
  • Fatigue
  • Upset Stomach
  • Spikes in blood pressure
  • Shortness of breath
  • Sweating
  • Increase or decrease in appetite
  • Dry mouth


Typically, the body will return back to normal stress levels after the stressor has gone away.  In people with chronic (long-term) stress, the body fails to return to normal levels. 

Their bodies sense danger even though there is no danger present.  This can have a number of negative effects on the body.

Chronic stress can make existing health issues worse. 

Stress can affect almost every system in the body.  If chronic stress goes untreated, it can suppress the immune system, making it much more difficult to recover from illness.

In addition, long-term stress can cause flare-ups in digestive diseases ulcerative colitis or Crohn's disease.

The body will dedicate energy to survival when it should be dedicating energy to healing itself.

Prolonged periods of stress may cause disease. 

Stress can significantly weaken the immune system, leaving the person much more susceptible to illness.  In addition, some people use unhealthy behaviors smoking or excessive drinking to cope with stress.  These behaviors can lead to disease in the long run.

There is also a possible link between stress and obesity.  Keep in mind that stress can make people overeat.  The article below outlines this further.

Chronic stress is also associated with heart disease.  As mentioned before, stress instantly causes a spike in heart rate and blood pressure.  This is fine as long as the heart can quickly return to normal levels. 

That doesn’t happen in people suffering from chronic stress.  The prolonged elevation of heart rate and blood pressure can damage the heart and ultimately cause heart disease.    

Digestive problems

Contrary to popular belief, stress does not cause stomach ulcers.  It can make them worse, however.

Stress can cause other digestive problems and impact which nutrients are absorbed during digestion.  Overeating brought on by stress can damage the stomach & intestines.

Skin problems

Sometimes, people suffering from stress will develop breakouts of acne.  Stress can also trigger flare-ups of existing skin problems, psoriasis.

Trouble sleeping

People who suffer from chronic stress will often lie awake late at night and think about what is stressing them out, making it difficult to fall asleep.  This can have negative impacts on the amount and quality of sleep.

Sleep is the body’s time for recovery.  If you don’t get enough sleep and your sleep is low-quality your body will not recover properly.

Mental Effects

The mental effects of stress can often be just as harmful as the physical effects.  Some of the mental effects can be managed effectively with simple strategies. 

However, stress can also be extremely overwhelming.  If you find that stress interferes with your daily life, go see a doctor or pharmacist.


Anxiety is characterized by racing thoughts and feelings of dread.  It is often coupled with an elevated heart rate and chest pain in extreme cases.

Memory Problems

Stress mainly effects short-term memory recall, but it can also impact long-term memory.

Lack of Concentration

Thoughts tend to rapidly jump from one to the next.  It can be difficult to concentrate on the task at hand because of intrusive thoughts related to stress.

Increased Negativity Towards Life

This is defined by having a negative outlook on everything.  Think of it as trying to find the negative aspects of everything in life.


If you are feeling overwhelmed, don’t hesitate to reach out to the National Suicide Lifeline.

Post-Traumatic Stress Disorder

After a traumatic event, people can develop Post-Traumatic Stress Disorder (PTSD).  The stress brought on by the event can cause flashbacks and periods of extreme stress.  People suffering from PTSD should seek professional help.

Stress Management

Good news:  a lot of the stress you encounter in everyday life can be managed through a variety of techniques.  Some of them are quick fixes and others require a strong commitment to stress management. 

Check out our stress management blog post for information on how to deal with stress.  


Stress hormones during pregnancy

The Role of CRH in Negative Health Effects of Stress

Natural changes in stress hormones during pregnancy

Prolonged, severe stress is bad for pregnancy. And stress hormones are to blame.

When stress hormone levels run very high, women are less ly to conceive and more ly to miscarry (Sapolsky 2004; Nepomaschy et al 2006). Babies are more ly to be born prematurely and underweight.

They are also more ly to experience developmental delays and metabolic diseases later in life (Sapolsky 2004; Poggi-Davis and Sandman 2006).

But this doesn’t mean that a healthy pregnancy is a pregnancy without elevated stress hormone levels. In this article, I review the normal hormonal changes that take place during pregnancy. I also explain:

  • How stress hormones help the fetus develop
  • How stress hormones may prime the maternal brain
  • The negative effects of hormonal changes on mom's mood

The negative effects of stress

When you perceive a crisis—-or think a stressful thought—-your brain secretes corticotrophin-releasing hormone (CRH). This master stress hormone triggers the release of glucocorticoid stress hormones, such as cortisol.

Stimulated by glucocorticoids and other stress hormones ( adrenaline), the brain and body shift into crisis mode. Your breathing and pulse quicken, making more oxygen available to your muscles. Blood sugar levels rise.

Physiological processes that are non-essential in the short term— digestion, growth, and repair—are temporarily shut down. You are in emergency mode. Mind alert, muscles ready for action (Sapolsky 2004).

When the crisis is over, your stress hormones are supposed to slip back to their previous, lower, baseline levels. But what if your baseline levels are pretty high? Elevated basal cortisol is usually bad news. It’s a sign that your body is on perpetual red alert. The body suffers more wear and tear (Sapolsky 2004).

For a pregnant woman and her fetus, high cortisol levels pose special risks. Elevated cortisol is associated with an increased risk of early miscarriage (Nepomaschy et al 2006). It can also cause preeclampsia (pregnancy-induced hypertension), fetal growth retardation, premature birth, and postnatal developmental delays (Reis et al 1999; Poggi-Davis and Sandman 2006).

Given these risks, we might expect healthy pregnancies to be characterized by low baseline cortisol levels. Surprisingly, this isn’t the case. Stress hormone levels rise.

The normal pattern

During the second trimester of pregnancy, circulating levels of corticotrophin-releasing hormone (CRH) increase exponentially (Mastorakos and Ilias 2003).

Ordinarily, such a surge would stimulate an overproduction of glucocorticoids in the mother. But messages are ineffective if nobody receives them, and hormonal messages are no exception.

To do its work, CRH must attach to special receptors in the brain (Dieterich et al 1999).

Pregnant women produce large quantities of a CRH-binding protein (“CRH-BP”) that prevent CRH from being recognized and used by receptors. As a result, most of the extra CRH is rendered biologically inactive (McLean and Smith 2001).

But the situation changes in the last weeks of pregnancy. In the last three weeks of gestation, CRH levels climb even higher. At the same time, CRH-binding proteins diminish. Suddenly, large quantities of CRH become available and biologically active (McLean and Smith 2001). This rise in biologically-active CRH coincides with a major spike in cortisol levels.

Cortisol levels begin to climb during the second trimester (Carr et al 1981), but they don’t reach their peak until in late pregnancy. In the last weeks before birth, cortisol levels are two to three times higher than normal (Dorr et al 1989).

These levels are high (Kammerer et al 2006)—in the same range as cortisol levels found in people with major melancholic depression and Cushing’s syndrome (a hormonal disorder associated with a variety of health problems and psychological disturbances—-see below).

What triggers the hormonal surge?

Elevated, prenatal stress hormones have been found in a number of mammals, including sheep (Keller-Wood 1998), rodents (Atkinson and Waddell 1995; Robinson et al 1989), and primates (Power and Schulkin 2006). Species may differ in the details, but one group—the anthropoids (human, monkeys and apes)—share a peculiar feature.

Ordinarily, CRH is secreted by the brain. But in pregnant anthropoids, the mother’s steep rise in circulating stress hormones is driven by the placenta—an organ controlled by fetal DNA. Genes from the fetus direct the placenta to secrete its own supply of hormones. And these hormones make their way into the mother’s bloodstream.

It’s not yet clear why the anthropoid placenta shows this distinction (Power and Shulkin 2006). But if the placenta is secreting all that extra CRH, one thing seems pretty certain. CRH must benefit the fetus.

How stress hormones help the fetus

What exactly are those prenatal stress hormones doing for the fetus? Researchers have uncovered several key functions.

In the first days of pregnancy, CRH suppresses the mother’s immune system, preventing the mother’s body from attacking the fetus (Makrigiannakis et al 2001).

Later, CRH helps regulate the blow flow between the placenta and the fetus (McLean and Smith 1999).

CRH may also help the fetal organs mature (Majzoub and Karalis 1999), and it appears influence the timing of birth (McLean and Smith 2001).

The late-term cortisol surge seems to play a role in brain development and the maturation of the lungs (Crowley 2000; Matthews et al 2004).

When babies are born prematurely (before the late-term cortisol surge), they are more ly to experience respiratory problems and interventricular hemorrhage (bleeding in the brain).

For this reason, the National Institutes of Health has recommended that women at risk for premature delivery be given synthetic cortisol (NIH Consensus Development Conference 1995).

CRH and cortisol may also make pregnant women less responsive to acute stressors (Kammerer et al 2002).

According to this idea, the stress response system adjusts to high basal cortisol levels by “tuning out” subsequent signals of stress.

In support of this hypothesis, women in the last stages of pregnancy showed no rise in cortisol after immersing their hands in ice cold water (Kammerer et al 2002).

Priming the brain for motherhood

One of the most interesting functions of stress hormones concerns maternal behavior. CRH-—or the hormones stimulated by CRH—-might help prepare the pregnant brain for motherhood.

For example, prenatal cortisol levels have been linked to more attentive mothering in baboons. In one study, the mothers who spent more time watching, grooming, and manipulating infants were the ones who had experienced higher cortisol levels during pregnancy (Bardi et al 2004).

Research on humans shows similar results. One study measured cortisol levels within 24-48 hours of giving birth—-a time period when women are still under the influence of prenatal hormones.

Researchers asked women to listen to the recorded cries of an infant, and they measured cortisol levels before and after the cries. The mothers who showed more sympathy to infant cries had higher baseline cortisol levels.

Moreover, higher-sympathy mothers had higher heart rates—both before and after hearing the infant cries (Stallings et al 2001).

Other research has reported that postpartum women with higher cortisol levels show

• more positive maternal behavior towards infants (Fleming et al 1987)

• an increased liking for their infants’ body odors (Fleming et al 1997), and

• an enhanced ability to distinguish their babies’ odors from those of other infants (Fleming et al 1997).

How do stress hormones influence maternal behavior? It’s still not clear. Possibly, the hormones have a direct effect on the mother’s brain, making women more vigilant and emotionally aroused (Stallings et al 2001).

Alternatively, higher cortisol levels may serve merely as a marker of other hormonal changes (Mastripieri 1999). Placental CRH, and the cortisol it stimulates, triggers the production of estrogen (Power and Shulkin 2006).

Estrogen, in turn, may make women more responsive to oxytocin and endorphins–the “feel good” brain chemistry that promotes bonding between mother and infant (Keverne 1996).

Unpleasant side effects

It seems that prenatal stress hormones have many beneficial effects.

But is there a downside? Ordinarily, high basal cortisol is diagnostic of Cushing’s syndrome, a condition associated with a variety of health problems and mood disorders, anxiety, irritability, mood swings, and insomnia (Sonino and Fava 2001).

High basal cortisol is also linked with melancholic depression (Kammerer et al 2006; Carroll et al 2007). Patients with melancholic depression lose their ability to experience pleasure or positive moods. They experience physical agitation, insomnia, and a reduced appetite.

Given these associations, it seems plausible that elevated stress hormones could contribute to mood changes in pregnant women (Kammerer et al 2006). And the psychological effects might extend to the postpartum period as well.

Some studies report that basal cortisol levels decline within a few days after childbirth (e.g., McLean and Smith 1999).

However, basal cortisol levels remain high in some postpartum women, and basal cortisol may not return to pre-pregnant levels until after 8 weeks postpartum (Kammerer et al 2002). This suggests that some postnatal mood disorders could be caused by elevated cortisol.

Interestingly, when postpartum rats were injected with the rat equivalent of cortisol, they showed signs of depressed behavior (Brummelte et al 2006).

But more research is needed to make a compelling case. Pregnancy and childbirth are associated with changes in many hormones, not just stress hormones. To identify cortisol as a cause of maternal mood disorders, the possible effects of other hormones must be teased out. Moreover, there is also the possibility that reduced cortisol causes mood problems.

When postpartum women experience a rapid withdrawal of cortisol shortly after birth, they may be at greater risk for developing “atypical” depression (Kammerer et al 2006). Despite its name, atypical depression is more common than melancholic depression (described above).

Patients with atypical depression retain the ability feel pleasure, and they eat and sleep more than healthy people do (Kammerer et al 2006).

Does motherhood buffer the effects of stress?

Finally, it’s not clear if pregnant and postpartum women feel stressors in the same way that other people do.

As noted above, elevated stress hormones may actually dampen the stress response system, making mothers less reactive—not more reactive—to stressful situations (Kammerer et al 2002).

In addition, postpartum mothers who breastfeed may enjoy special protective effects against stress. After they are exposed to a stressor, women who breastfeed have lower levels of cortisol than do non-breastfeeding controls (Heinrichs et al 2002).


Click here for references cited in this article about stress hormones during pregnancy.

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