The NeuroEndoMetabolic (NEM) Stress Response model says there are six interrelated organ systems in the body: the bioenergetic circuit, the hormone circuit, the neuroaffect circuit, the cardionomic circuit, the inflammatory circuit, and the detoxification circuit. When the body is in a healthy state, these systems work in conjunction with one another to maintain homeostasis. However, when stress takes over the body and continues to the point of causing health issues, one or more of these organ systems is affected. Due to the inter-relationships among these organ systems, what affects one causes effects in others. By addressing and intervening in these organ systems, practitioners can get to the root causes of symptoms and begin a more effective intervention effort.
The bioenergetic circuit is a major part of the NEM stress response. It consists of the pancreas, thyroid, and liver. It’s important to review this area thoroughly. Cortisol, insulin, and thyroid are all vital hormones in the body, and the levels of each one have a major impact on levels of the others. They are essential to the operation of the bioenergetic circuit and understanding how to maintain it in good health. When there is an imbalance in these hormones, adrenal fatigue and obesity are often the first results of a continually worsening parade of health concerns. Getting these hormones in balance is vital to your health.
However, before exploring how they interact, it is important to understand the function of each of these hormones individually.
Cortisol is the body’s stress-fighting hormone. It is produced by the adrenal glands every time stress strikes your body. Stress stimulates the hypothalamic-pituitary-adrenal (HPA) axis, resulting in the adrenals secreting cortisol to fight or flee from the stressor. Once the stress is handled, cortisol returns to normal. However, in our stress-laden world, it often happens that stress continues unabated, which places an extraordinary burden on your adrenals to continue secreting cortisol. The adrenals become exhausted and no longer produce adequate cortisol to fight stress. This is when symptoms of Adrenal Fatigue Syndrome (AFS) begin.
This picture of cortisol is a simplified example, however. Cortisol actually has a much more complex set of duties in your body. In addition to regulating blood pressure and heart functioning, it also affects your body’s use of proteins, carbohydrates, and fats. In the bloodstream, cortisol helps break down proteins in your muscles, releasing amino acids which the liver uses to convert glucose into energy. The energy stored in fat cells is also released when cortisol is secreted. This supplies sufficient energy for your body to use in dealing with stress.
Problems result when stress becomes chronic and your adrenals continue secreting cortisol. High levels of cortisol lead to difficulty sleeping. Lack of sleep eventually leads to more hormonal imbalance and to the initiation of degenerative conditions. Women experience lower levels of estrogen when sleep deprived. This then puts them under even more stress. Some of the symptoms and conditions that may indicate high levels of cortisol include osteoporosis, fibromyalgia, cravings for sugar or salt, allergies, and digestive problems.
At the other extreme, low levels of cortisol affect your mood. You can suffer from increased anxiety and become upset by things you would normally ignore. Having extreme difficulty deciding whether to face stress head on or flee from it is a sign of low cortisol. Another indicator of this condition is difficulty thinking clearly when under stress. Weight gain, especially around the middle of the body, is another sign of low cortisol. This occurs when people begin eating more to try to make up for low energy levels. Much of the time, they eat high-calorie foods for the quick energy release. The result of this overeating is not only weight gain, but also a sharper decline in energy shortly after eating.
Cortisol normally declines with increasing age, making the effects of stress more harmful to people as they age. This leaves the elderly more susceptible to heart-related conditions and cancer. The deficiency in cortisol leaves them vulnerable to stress-related health conditions.
A balance between the cortisol, insulin, and thyroid hormones protects your body and bioenergetic circuit from the damage that can result from elevations in one alone.
Secreted from the pancreas, insulin is part of the bioenergetic circuit of hormones. Insulin levels are related to diabetes. Even though this is well-known, people in this country continue to consume processed foods containing carbohydrates that significantly affect insulin levels. This behavior pushes them to the edge of developing diabetes. These kinds of foods have an addictive quality that makes it very difficult to stop consuming them, and the people who overeat them continue to live in denial that these foods contribute to the development of diabetes.
Some of the symptoms of low blood sugar include irritability, dizziness, poor memory and coordination, craving for sweets, fatigue, and mood swings. If your blood sugar gets low enough, you feel a loss of energy, loss of physical strength, and the potential increases for passing out or even dying.
Blood sugar, or glucose, is the fuel for the body. When it is in balance, it enables you to think clearly and function well physically. Consuming carbohydrates excessively causes a significant imbalance in blood sugar because all carbohydrates are broken down into glucose in your body. Eating too much of these carbs will send your blood sugar levels into sometimes large swings that interfere with its appropriate balance.
Your pancreas, which is one of the organs of the bioenergetic circuit, uses insulin to control the level of sugar in your blood. Insulin pushes this blood sugar into your cells. If it does this too much, it leads to a low level of sugar in your blood. This results in too-low energy levels and swings in your mood. The continual presence of too much insulin can lead to metabolic disturbances and even diabetes.
Insulin levels that are too high are associated with increasing weight gain because your body has a hard time breaking down fat. This can lead to an increase in blood pressure and free radicals, which speeds aging and can lead to health conditions.
The foundation that protects against high insulin levels is the balance of hormones. The balance of cortisol, insulin, and thyroid hormones protect the body from damage due to high levels of any one of them.
The thyroid is a very important hormone in this triad of hormones and in the bioenergetic circuit of NEM. The reason it is so important is its primary role in cellular energy production. When the thyroid hormone gets low, all other hormones are negatively affected.
A thyroid gland that doesn’t function well will have a negative impact on just about every aspect of health. This includes your energy level, mental outlook, weight, body temperature, and the condition of your skin and hair.
Low thyroid levels bring on fatigue, dry skin, weight gain that isn’t explained, sleep apnea, high blood pressure, muscle weakness, chronic pain, and susceptibility to infections. Metabolism and energy production are both slowed by low thyroid levels. This explains why people with low thyroid issues are often cold and constipated. When they eat how they always did, they gain weight.
One of the factors that negatively affects thyroid functioning is decreased adrenal gland functioning.
The mitochondria are located at the center of every cell. They are often called the cellular furnace. Cellular energy is produced in the mitochondria, and thyroid hormone is the fuel of that furnace. When thyroid hormone gets too low, the furnace produces less energy. Those with too low thyroid hormone suffer from this lack of energy that can ultimately result in not being able to stay awake or even death.
Problems with the thyroid progress slowly and can occur at any age. Estimates are that up to 27 million people in the U.S. suffer from undiagnosed thyroid dysfunction; most of these sufferers are women. Depression and panic attacks may occur with thyroid dysfunction and seem to happen largely for women. Feeling tired after a night’s sleep and requiring naps during the day to make it through the day is a result of thyroid problems. Another symptom is your body shifting thyroid from your hair, nails, and skin to more critical functions of the body. This leads to brittle hair and nails, along with dry skin.
Most of the time, evaluation to determine whether your thyroid is functioning well involves determining the presence of the thyroid stimulating hormone, TSH. In the usual use of this test, a low score indicates no TSH, therefore no need for your body to stimulate the thyroid since it is working well. A high score indicates a dysfunctional thyroid. Because this is not sufficient to determine whether your thyroid is dysfunctional, you should insist on measuring free T3 and free T4 levels as well.
The hormonal and bioenergetic circuit are primarily involved with the maintenance of cortisol, thyroid, and insulin levels, and the organs that maintain those hormones, the adrenals, the thyroid, and the pancreas. There is also some involvement of the cardionomic circuit. Because of the inter-relationship of the circuits in the NEM stress response model, what affects one of these circuits affects the others.
The pancreas and thyroid hormones, insulin and TSH, along with T3 and T4, exert an effect on metabolism and hormones. In order for your metabolism to remain healthy, glucose is required for fuel. If there is an imbalance in the triad of too little or too much insulin, there will be a significant effect on the bioenergetic circuit.
A weak metabolism can lead to a slow detoxification process and decreased nutrients being delivered to your cells. This will inhibit your ability to deal with stress and its effects on your body.
With continuing stress, the body requires more glucose to keep it geared up for dealing with whatever stress it encounters. This requires an increase in your basal metabolic rate. Imbalances in the thyroid-pancreas-liver interaction prevent this increase from occurring, allowing stress to wreak havoc on your body.
The thyroid is the gland that regulates the speed of your metabolism. If you have an imbalance in this triad that involves low levels of thyroid hormone, your metabolism will be slowed significantly. On the other hand, an imbalance that causes too much thyroid hormone will lead to an increase in your metabolism, burning up the nutrients in your food too rapidly.
Working together, the thyroid hormones and insulin control how effective your metabolic processes will be.
The other main circuit involved in this triad is the hormone circuit. Cortisol secreted by the adrenal glands is one of the most important hormones involved in adrenal fatigue and stress. When your body is under stress, your adrenals secrete cortisol. Continuing stress can lead to adrenal fatigue and a decrease in cortisol. Lower cortisol levels lead to lower thyroid functioning. This lower functioning of your thyroid leads to feelings of fatigue. It also slows your ability to respond to stress.
Your body attempts to conserve energy in your stressed state by slowing your thyroid function and metabolism even more. In contrast to the methods employed in integrative medicine, conventionally trained physicians often overlook the metabolic component and institute hormone therapy to stimulate the thyroid, covering up the underlying issue.
The adrenal hormones also affect the cardionomic circuit. Keeping the heart and lungs functioning appropriately is important for the fight or flight response. Norepinephrine and adrenaline are the two main hormones involved in this function. Adrenaline, or epinephrine, is the most powerful stimulant hormone your body produces. Both of these hormones are secreted by the adrenals. With the adrenals depleted due to continuing stress, these two hormones will also be in short supply. Continuing stress leads to an imbalance of the hormones from the adrenals.
As has been said above, the balance of these three hormones is important for your continuing good health. One of the main tenets of the bioenergetic circuit is that these three hormones affect one another.
A very important function of cortisol is to act in a synergistic way with thyroid hormone at the level of receptor genes. An appropriate level of cortisol is important for good thyroid functioning. Because of this synergy, it is possible for people with imbalanced cortisol levels to have normal thyroid levels but show symptoms of an out of balance thyroid.
All cells of your body have receptors for cortisol and thyroid. Every function of your cells needs appropriate levels of thyroid hormone to work efficiently.
If the imbalance in your body involves overly high levels of cortisol, such as in the early stages of adrenal fatigue when the adrenals are overworked, your cells may no longer respond to signals from the thyroid. This brings on a condition called thyroid resistance. In this case, you may have normal thyroid hormone levels, but your cells don’t respond well to signals from the thyroid. When this resistance to thyroid occurs due to high levels of cortisol, other hormones including insulin are also affected. This resistance leads to the necessity of higher levels of hormones to produce the desired effect. When under chronic stress, with increased cortisol, you will feel physically beat because none of your hormones are working effectively.
For example, when cortisol is high, insulin resistance increases. This means your body requires more insulin to push it into your cells. This situation will lead you to gain weight around the middle of your body because you’re not burning fat but storing it. This is one of the reasons you will gain this kind of stubborn belly fat under conditions of adrenal fatigue.
Under conditions of high cortisol, women’s brains become less sensitive to estrogen. This is not a situation of low estrogen but changed brain receptors. Many non-integrative medicine physicians will add estrogen, thinking supplementation is needed to increase estrogen levels. Instead, it will push them into estrogen dominance which can lead to weight gain around the hips, retaining water, and mood swings.
Both high and low cortisol levels affect thyroid hormones. And both high and low levels of cortisol are brought on by continuing stress. In the early stages of high stress, your adrenals are producing a lot of cortisol to fight it. Later, as your adrenals become fatigued because of unrelenting stress, they do not produce sufficient cortisol. Cortisol that is too high or too low leads to resistance to the rest of your hormones, including thyroid and insulin.
Cortisol decreases levels of TSH, the thyroid hormone. It also decreases conversion of T4 to active T3 and increases conversion of T4 to reverse T3.
Imbalances in cortisol also affect your blood sugar levels. Changes that lead to imbalances in cortisol, either high or low, can bring on hypoglycemia, hyperglycemia, or both. These imbalances in blood sugar affect your levels of insulin secreted by the pancreas. They also inhibit functioning of your thyroid gland and the bioenergetic circuit.
Another way cortisol levels affect the functioning of your thyroid is through its effects on your liver. Continuing high levels of cortisol inhibit your liver’s ability to remove excess estrogen from your blood. This leaves high levels of estrogen in your blood, which increases levels of thyroid TBG, the protein thyroid hormone binds to in your bloodstream.
Binding to TBG keeps the thyroid hormone inactive. It has to be separated from the TBG to become free fraction which allows it to stimulate receptors in your cells. Lab tests measure this kind of thyroid hormone as free T3 and free T4. High levels of TBG means low levels of free thyroid hormone.
Insulin is also involved in this triad. Insulin is produced in the pancreas, one of the organs of the bioenergetic circuit. When there you have high cortisol, insulin resistance results, making it hard for your cells to receive insulin. This results in two things. First, you have less energy because your cells can’t utilize glucose effectively. Second, high blood sugar levels develop because the glucose stays in your bloodstream instead of going into your cells.
Research indicates insulin resistance is closely associated with thyroid problems. Altered lipid levels and issues with the secretion of insulin are part of the complicated relationship between hormones involved in hypothyroidism and hyperthyroidism.
A study published in the International Journal of Health Sciences and Research showed a dysfunction in your thyroid leads to changes in lipid and glucose metabolism. This is a major risk factor for the development of cardiovascular disorders. In addition, a blood glucose related disorder called diabetes dyslipidemia can result.
Hypothyroidism has been shown to have a strong association with increased levels of insulin and increased insulin resistance. It also has been shown to decrease T3 and T4 hormones and increase TSH. This indicates an increased risk of developing health issues related to insulin resistance with hypothyroidism.
Estimates are that between 60 and 70 million people in the U.S. have insulin resistance. Forty percent of those over the age of 50 are more susceptible to this condition. Insulin resistance is often the precursor to type 2 diabetes and is part of metabolic syndrome.
Metabolic syndrome as understood in integrative medicine is a combination of several conditions including high blood pressure, gaining excess fat around the waist, increased blood sugar levels, and high levels of triglycerides and cholesterol.
With this combination of conditions, there is a greatly increased risk of stroke, diabetes, and heart attack. Being overweight or obese and living a sedentary lifestyle make this condition more likely. Increased insulin resistance is said to be a cause of this metabolic syndrome.
Ongoing research confirms that both hypothyroidism and hyperthyroidism have significant associations with metabolic syndrome. Much of this association has to do with the effects of thyroid hormones on insulin.
Clearly, insulin has a significant effect on blood sugar. In addition, blood sugar levels are affected by a balance between how much glucose is synthesized (gluconeogenesis) and glucose ingestion. These levels are also affected by the metabolism of glucose and its dispersal in target tissues.
Glucose has to be transported to the target cells, and hypothyroidism decreases this transport in myocytes or muscle cells. This transport is regulated by glucose transporters on cell surfaces, controlling how much glucose gets into your cells. In hyperthyroidism, these transporter cells are stimulated, increasing the amount of glucose in your cells and decreasing it in your bloodstream. This shows the significant effect of thyroid hormones on secretion and clearance of insulin.
Studies have shown a significant number of people with metabolic syndrome to also suffer from thyroid problems. Women seem to suffer from both conditions more frequently than men. Larger waist circumference and lower HDL levels were prevalent among people with metabolic syndrome who also had thyroid dysfunction. Thus it is so important to have a balance in the bioenergetic circuit.
Studies have also shown an increased risk of developing type 2 diabetes when TSH levels are high and T4 levels are low. This combination of thyroid hormones in the bioenergetic circuit, also increases the risk of progression from prediabetes to diabetes.
Type 2 diabetes is the most frequently seen form of diabetes and indicates blood sugar levels are too high. Estimates are that over 29 million people in the U.S. have diabetes, and some are completely unaware they have the condition. Other estimates suggest one-third of people in the U.S. will develop type 2 diabetes at some time in their lives.
Some of the factors involved the connection between low thyroid function and the increased risk of diabetes include lowered insulin sensitivity, decreased ability of insulin to enable the use of glucose in muscle leading to tolerance of blood sugar, and decreased effectiveness of glucose transporters on plasma membranes. That is why the pancreas, thyroid, and liver all play major roles in the bioenergetic circuit in metabolism and insulin resistance.
An interesting finding has been that high and high-normal thyroid hormone levels show a protective effect against the development of and progression to diabetes. This is in spite of the evidence linking hyperthyroidism to increased insulin resistance.
One reason for this supported by research is that this insulin resistance is balanced out by other factors associated with continued high levels of thyroid hormone.
Much research has been conducted into high levels of glucose, but it is important to keep in mind there are significant health problems that can arise due to low glucose levels, as well. Low blood sugar, or hypoglycemia, occurs when you don’t have sufficient glucose for energy production in your cells. The main causes include some medications, endocrine problems, tumors, and some medical conditions.
One more way research shows the relationship between the thyroid and hypoglycemia is that hypothyroidism is associated with some biochemical, nervous system, and hormonal problems that potentially lead to hypoglycemia. Hypothyroidism is associated with low growth hormone levels and cortisol responses to insulin-induced hypoglycemia. This association is through a blockage of regulatory protection against hypoglycemia.
The adrenals secret more cortisol when blood sugar levels decrease. Cortisol then stimulates your liver to produce greater amounts of blood sugar, bringing the levels to normal.
However, pituitary functioning is suppressed when the adrenals continue to secrete cortisol in people with hypoglycemia. Your thyroid must have adequate pituitary functioning in order for it to function properly.
A dysfunctional pituitary gland can also be caused by hypothyroidism. In this case, the cause-effect sequence may be low thyroid hormone leading to low functioning pituitary rather than the other way around.
Yet another indication of the relationship among the triad hormones is seen in the impairment of gluconeogenesis and glycogenolysis in people with low thyroid hormones. This makes it more difficult for these people to recover from hypoglycemia.
Any kind of stress triggers the hypothalamic-pituitary-adrenal (HPA) axis. With continuing stress, the HPA axis can be continually triggered, resulting in high levels of cortisol. Ultimately, the adrenals become exhausted and can’t produce enough cortisol. This is the beginning of AFS.
But while high levels of cortisol are circulating, health difficulties can occur. Normally, cortisol is at its highest level in the morning and affects your entire body. It typically affects metabolic process the most, but also has effects on your immune response, ion transport, and memory.
Its metabolic effects come through its actions on blood sugar levels and gluconeogenesis. Cortisol counters insulin, leading to higher blood sugar levels. The mechanism by which the metabolic effects of the bioenergetic circuit comes about begins with cortisol stimulating the expression of enzymes which are critical for gluconeogenesis, which increases production of glucose. At the same time, it also stimulates the liver to synthesize glycogen which lowers blood glucose levels. In this way, cortisol regulates the level of blood sugar in your bloodstream. These effects of cortisol on metabolism are shown in how it maintains sufficient levels of blood sugar during fasting through gluconeogenesis.
With the potential for decreased secretion of cortisol due to excess HPA activation, its control of blood sugar levels can quickly become dysfunctional, leading to significant problems with metabolism.
Cortisol’s ability to control ion regulation is shown in how it prevents loss of sodium and stimulates the excretion of potassium. Keeping these two substances in balance helps keep your body’s pH regulated and helps your body re-stabilize after any event that disturbs their balance.
Cortisol also weakens your immune system functioning. It appears to prevent some T-lymphocyte cells from recognizing interleukin signals. T-cells are essential in cell-mediated immunity. These effects result in some people becoming more susceptible to infection.
The hippocampus, a region in the center of the brain, has more receptors for cortisol than any other region of the brain. The hippocampus is the area of the brain involved in memory. Normal levels of cortisol have no effect on the hippocampus, but high levels overwhelm it. Continuing stress with accompanying high levels of cortisol can lead to actual damage to the hippocampus. If stress continues, the hippocampus may even physically shrink.
The hippocampus is extremely important for learning and transferring material in short-term memory into long-term memory. A great deal of neuronal activity is required for this to occur. Significant amounts of neurogenesis also take place in the hippocampus. Thus, serious limitations to the hippocampus can be highly detrimental to your ability to learn.
This brain region also can be significantly affected by continuing stress because of the effects of cortisol. Under ongoing stress, the number of neurons added to or taken from the hippocampus is affected by cortisol. Cortisol also stimulates the amygdala, a brain region close to the hippocampus, while it inhibits the hippocampus. This causes you to pay a lot of attention to your emotions while having trouble taking in new information. This not only brings into account the bioenergetic circuit, but also the neuroaffect circuit of the NEM Stress Response System.
Another way these hormones impacts the bioenergetic circuit is through flattened cortisol levels throughout the day. Normally, cortisol is higher in the morning to help you wake up, then gradually decreases throughout the day until it is at its lowest at bedtime.
However, continuing stress can lead to cortisol levels that are high at all times of the day and night. Over time, high cortisol levels cause all kinds of physical problems. Some of these include:
Susceptibility to infections
When conditions of continuing stress cause cortisol levels to stay consistently high or low, the natural curve seen with normal levels of cortisol flattens.
If you have high levels of cortisol early in the morning, you may awaken at 3 or 4 a.m. and not be able to return to sleep. As soon as you awaken, your mind is racing. You may also be irritable in the mornings. Some time in midmorning, your energy level typically crashes.
This will also keep your cortisol levels high during the day. You may feel both exhausted and hyper. Your speech may sound extra fast. You may feel like you can’t catch up during the day. You likely feel more irritable than usual.
High cortisol levels in the evening make it difficult to fall asleep, sometimes taking hours to drift off. Arguing and worry tend to be prevalent as well.
Another part of this flattened cortisol curve is low cortisol, and symptoms of this can be much more problematic. During the day, you feel like you’re lacking energy even after a good night’s sleep. Either strong coffee or lots of exercise is needed to get you going, but the effect doesn’t last long. It’s easy for you to fall asleep, even in meetings.
At night, you may be able to fall asleep for a short time, but often you wake in the middle of the night for no apparent reason and are unable to get back to sleep. The entire sleep cycle can be disrupted, leading to significant insomnia and a sense of dragging the following day. This causes more stress and becomes a vicious cycle that tends to get worse until the cortisol curve is normalized. Differing cortisol levels can also change your body's metabolism in the bioenergetic circuit.
High or low levels of any of these three hormones can be detrimental to your health. Integrative medicine practitioners suggest several approaches to balancing the triad and restoring your bioenergetic circuit back to health.
A diet rich in fiber, healthy fats, and proteins will help stabilize your blood sugar when you do consume carbohydrates.
Regular physical activity is necessary because it stimulates your muscles to consume more glucose and your cells to become more sensitive to insulin.
Probably the most important part is to control stress. There are multiple ways to reduce and control the amount of stress you experience.
It is also important not to skip meals. Especially breakfast. Skipping meals will increase your blood sugar levels and can lead you to gain weight.
Getting sufficient amounts of sleep also is an important part of this integrative medicine protocol. Sleep increases your energy, reduces cortisol, and fights stress.
It’s also important to cycle your intake of carbs. This cycle involves reduced consumption of carbs in the morning, moderate amounts in the middle of the day, and high levels of carbs in the evening. The mechanism works like this: High carb intake decreases cortisol levels and low carb consumption increases cortisol levels. Consuming carbs increases blood sugar levels also. This stimulates the pancreas to produce more insulin which then lowers cortisol production.
Research indicates supplementing with Omega 3 fatty acids, along with vitamins C and B5 will help stabilize your cortisol curve.
It is vital to stay hydrated.
The bioenergetic circuit of the NEM stress response refers to several organ systems in your body charged with metabolizing and digesting nutrients, and how they respond as a group to stressors. This circuit is closely related to other circuits such as the hormonal circuit. The cortisol-insulin-thyroid triad has a major effect on this circuit and every part of health.