Christian
Active Member, June10MOTM
Cortisol and memory and the nervous system
High levels of cortisol interfere with memory. If the stress is short term (ie less than 6 months) the effect is not permanent, and memory will return to normal once cortisol levels drop. However, repeated and long-term stress can atrophy or shrink the hippocampus the very part of the brain where we store memories.
Cortisol affects long-term memory more than short-term recall. You can still learn under stress, but it’s harder to recall after 24 hours.
We are able to create new brain cells all our lives, they don’t have to diminish with age. However, in a study by the American National Institute of Health it showed that cortisol, significantly reduces our bodies ability to grow new brain cells.
A study reported in the International Journal of Neuroscience found that high stress levels could be linked with the onset of Alzheimer’s disease. Research into drugs that lower cortisol levels is being pursued.
Muscle
Cortisol reduces protein synthesis, and increases protein breakdown. This translates to loss of muscle tissue and poor wound healing. With lots of stress our muscles get weak and lose tone, also increasing risk of osteoporosis.
Heart Disease
Stress is more powerful than diet in influencing cholesterol levels. Several studies including one of medical students around exam time and another of accountants during tax season, have shown significant increases in cholesterol levels, when there was little change in diet.
Dr. Paul Rosch, Professor of Medicine New York Medical College)
Severe stress is one of the most potent risk factors for stroke, even 50 years after the initial trauma. In study of 556 WWII veterans, the rate of stroke among those who had been prisoners of war was 8 times higher than among those not captured.
Alan Young MD Cardiologist Harvard Medical
Chronic stress linked with increased platelets and fibrinogen, high cortisol levels increase aldosterone, (increasing blood volume and pressure), Excess cortisol increases High Density Lipid ratio and Increases BMI. MI waiting to happen!
Overweight
Elevated cortisol increases insulin production. With a chronic elevated cortisol, there is an increase in abdominal fat, which is a risk factor for heart disease and diabetes.
When cortisol is secreted, so is aldosterone, which causes an increase in fluid retention.
Diabetes
Elevated cortisol decreases glucose uptake into cells and thus glucose utilisation. Cortisol is diabetogenic, either aggravating existing diabetes, unmasking latent diabetes or causing insulin resistance.
Immune system
Acute stress i.e. no more that 3-5 days can increase immunity battle stations, in the middle of a crisis, you rarely get sick, but the minute the alarm bells have finished you are wide open to infection.
Longer-term stress with its higher cortisol output decreases the number of immune cells - eosinophils and lymphocytes in the blood. In addition large doses of cortisol causes significant shrinkage of all the lymphoid tissue (the lymph is where the immune cells mature and travel) throughout the body, which in turn decreases the output of both T cells and antibodies. As a result the level of immunity for almost all foreign invaders of the body is decreased.
This ability of cortisol to suppress immunity makes it of use to prevent immunological rejection of transplanted hearts etc. explains why transplant patients are at risk of getting infections.
A study looked at one marker of the immune system - S-IgA (Salivary immunoglobulin) found in mucosal secretions. It is the first line of defence against pathogens in mouth and gastrointestinal tract, urinary tract and throat and lungs. The study showed various videos to the participants. One video was of Mother Theresa doing work with the dying in India. The participants noted feeling of love, compassion, and tranquillity and lo and behold an immediate increase in S-IgA was observed. S-IgA will increase in positive mood states. Then a ‘feel bad’ violent video was shown and the participants noted feelings of frustration, aggravation and resentment, and the S-IgA levels fell.
In yet another study 400 people were exposed to the cold virus. It is often the strength of our immune system that decides whether we ‘catch’ viruses. Otherwise everyone would catch every virus. Those who scored highest on the test of stressful life events were more than twice as likely to develop colds after exposure than people who scored lowest.
Cancer
A study in 2000 in the Journal of the National Cancer Institute found that cancer patients with high stress levels were less likely to live as long as patients who coped well with stress. Although no one knows the reason for cancer, a healthy immune system is better equipped to kill cancer cells as they are formed.
Rats unable to escape electric shocks had earlier tumour appearance and decreased survival time compared to rats who could escape.
Depression & Stress
High proportion of depressed patients show elevated cortisol, evidence that high cortisol may contribute to depression rather than being a reflection of the disease. Jacobson
High levels of cortisol interfere with memory. If the stress is short term (ie less than 6 months) the effect is not permanent, and memory will return to normal once cortisol levels drop. However, repeated and long-term stress can atrophy or shrink the hippocampus the very part of the brain where we store memories.
Cortisol affects long-term memory more than short-term recall. You can still learn under stress, but it’s harder to recall after 24 hours.
We are able to create new brain cells all our lives, they don’t have to diminish with age. However, in a study by the American National Institute of Health it showed that cortisol, significantly reduces our bodies ability to grow new brain cells.
A study reported in the International Journal of Neuroscience found that high stress levels could be linked with the onset of Alzheimer’s disease. Research into drugs that lower cortisol levels is being pursued.
Muscle
Cortisol reduces protein synthesis, and increases protein breakdown. This translates to loss of muscle tissue and poor wound healing. With lots of stress our muscles get weak and lose tone, also increasing risk of osteoporosis.
Heart Disease
Stress is more powerful than diet in influencing cholesterol levels. Several studies including one of medical students around exam time and another of accountants during tax season, have shown significant increases in cholesterol levels, when there was little change in diet.
Dr. Paul Rosch, Professor of Medicine New York Medical College)
Severe stress is one of the most potent risk factors for stroke, even 50 years after the initial trauma. In study of 556 WWII veterans, the rate of stroke among those who had been prisoners of war was 8 times higher than among those not captured.
Alan Young MD Cardiologist Harvard Medical
Chronic stress linked with increased platelets and fibrinogen, high cortisol levels increase aldosterone, (increasing blood volume and pressure), Excess cortisol increases High Density Lipid ratio and Increases BMI. MI waiting to happen!
Overweight
Elevated cortisol increases insulin production. With a chronic elevated cortisol, there is an increase in abdominal fat, which is a risk factor for heart disease and diabetes.
When cortisol is secreted, so is aldosterone, which causes an increase in fluid retention.
Diabetes
Elevated cortisol decreases glucose uptake into cells and thus glucose utilisation. Cortisol is diabetogenic, either aggravating existing diabetes, unmasking latent diabetes or causing insulin resistance.
Immune system
Acute stress i.e. no more that 3-5 days can increase immunity battle stations, in the middle of a crisis, you rarely get sick, but the minute the alarm bells have finished you are wide open to infection.
Longer-term stress with its higher cortisol output decreases the number of immune cells - eosinophils and lymphocytes in the blood. In addition large doses of cortisol causes significant shrinkage of all the lymphoid tissue (the lymph is where the immune cells mature and travel) throughout the body, which in turn decreases the output of both T cells and antibodies. As a result the level of immunity for almost all foreign invaders of the body is decreased.
This ability of cortisol to suppress immunity makes it of use to prevent immunological rejection of transplanted hearts etc. explains why transplant patients are at risk of getting infections.
A study looked at one marker of the immune system - S-IgA (Salivary immunoglobulin) found in mucosal secretions. It is the first line of defence against pathogens in mouth and gastrointestinal tract, urinary tract and throat and lungs. The study showed various videos to the participants. One video was of Mother Theresa doing work with the dying in India. The participants noted feeling of love, compassion, and tranquillity and lo and behold an immediate increase in S-IgA was observed. S-IgA will increase in positive mood states. Then a ‘feel bad’ violent video was shown and the participants noted feelings of frustration, aggravation and resentment, and the S-IgA levels fell.
In yet another study 400 people were exposed to the cold virus. It is often the strength of our immune system that decides whether we ‘catch’ viruses. Otherwise everyone would catch every virus. Those who scored highest on the test of stressful life events were more than twice as likely to develop colds after exposure than people who scored lowest.
Cancer
A study in 2000 in the Journal of the National Cancer Institute found that cancer patients with high stress levels were less likely to live as long as patients who coped well with stress. Although no one knows the reason for cancer, a healthy immune system is better equipped to kill cancer cells as they are formed.
Rats unable to escape electric shocks had earlier tumour appearance and decreased survival time compared to rats who could escape.
Depression & Stress
High proportion of depressed patients show elevated cortisol, evidence that high cortisol may contribute to depression rather than being a reflection of the disease. Jacobson