Stress, Cortisol and Immunity

In today’s unpredictable environment of world-wide pandemics, health concerns and economic uncertainty, it is easy to succumb to the negative effects of stress on the body. We are being exposed to a greater variety of stressors daily. We may think that one type of stress is better or worse than another, but in reality, the body interprets and responds to all stress in the same manner: cortisol release. You may have heard cortisol described as the “stress hormone.” When the body experiences stress, cortisol and catecholamines are released from the adrenal cortex which activate the “fight-or-flight” mechanism. This mechanism prepares us for self defence and survival and is intended for short-term bursts of energy and heightened function. Cortisol causes the release of sugar into the blood so that we have energy to deal with the stress, moves blood away from the organs to the peripheral muscles to be ready to move the body, increases blood pressure by improving the sensitivity of the vessels to adrenaline, decreases bone formation, acts as a diuretic by excreting water, and heightens awareness. Among these effects is suppressed immunity, which opens the door to infection and a poor inflammatory response.

Stress and Illness: Understanding the Connection

When we get sick, the fever, stuffy nose, phlegm build-up and swollen lymph nodes are not the result of the infection itself, but rather they are the result of the immune system fighting the infection. Our immune system responds to infection with a flux of white blood cells to the infected area, and it is their activity that causes the symptoms. The inflammatory response to sickness or injury is also the result of the immune system trying to heal the tissues by bringing a flood of plasma (blood), white blood cells and nutrients to the injured area. When stress is present, cortisol is released, and our body is primed to deal with the stressor. When cortisol returns to baseline levels, the suppression is removed. This is why we often seem to get sick after a stressful situation has passed, such as after exams, a stressful time at work, family events, and so on. It’s not that we’ve gotten sick, but rather that the immune system is finally responding to the infection.

If stress remains for a lengthy period of time, hypercortisolemia can occur, which is a higher than normal level of cortisol in the blood. This creates a longer period of time during which bone maintenance is diminished, sleep is not restful, tissue repair is slowed, and cells are less sensitive to insulin which causes high blood sugar. In fact, research has shown stress to be related to many of the illnesses that devastate our society. In cases of chronic stress, a condition called adrenal insufficiency (also known as adrenal fatigue) may occur. This results when the adrenal cortex has been so overworked through chronic stimulation that the adrenals experience “burn-out” or fatigue and can no longer produce enough hormones for proper stress response and function. This can lead to chronic fatigue, illness  and a poor inflammatory response, among other things. Fortunately, with proper care, this can be reversible. 

Here are some of the common symptoms associated with adrenal dysfunction.  

Most common and distinctive symptoms include: 

  • Morning tiredness
  • Exhaustion after exercising
  • Cold hands and feet
  • Very sensitive to environmental changes
  • Emotionally hypersensitive
  • Brain fog, concentration and memory problems
  • Inability to cope with changes and stress
  • Low blood pressure, light-headedness, salt craving
  • Low blood sugar – “hangry”
  • Multiple allergies/ sensitivities
  • Low immunity and infections
  • Poor inflammatory response
  • Decreased sex drive

The Importance of Good Nutrition

Nutritional stress includes what we eat and what we don’t eat. Today, we eat less fresh, unadulterated food and consume more processed, preserved foods than ever before. We do not only need calories from food for energy, we need also the vitamins, minerals and phytonutrients that are present in food in just the right amounts so that they can work synergistically to promote health. Food that has been enriched has been stripped of most of its nutritional value through the refining process and only some of it is replaced. Heat and chemical processing may remove or kill many of the nutritional elements that are naturally present in food. The body will also use nutrients from its own reserves or need higher than normal levels to support itself during a stress or an infection. All of this causes stress throughout the body because it is not getting what it needs to function properly. This will eventually lead to the exhaustion of non-primary bodily processes, hormonal imbalances, and illness. 

One example of a vitamin impacted by both acute and chronic stress is vitamin C. The adrenal gland is responsible for producing hormones in response to stressful events.  It has the highest concentration of vitamin C in the body. Here it is used as a cofactor for the production of epinephrine and steroid hormones. During times of stress and infections the demand for the production of these hormones increases so the body naturally has a higher demand for vitamin C. The cells of the immune system need much higher levels of vitamin C when they are responding to an infection which can quickly lead to a deficiency in other tissues. 

Other nutrients and botanical extracts can also be helpful to manage the symptoms of stress over and above of the suggestions in this article. See the chart below. 

Supplement Comments and Research Summary
Glycyrrhiza glabra (Licorice) It has been shown to activate the receptors for key adrenal hormones (mineralocorticoids and glucocorticoids) involved in mobilizing energy reserves in response to stress. The active component, glycyrrhizin also helps to keep these hormones in their more active forms and it also has an antiviral effect.
Ashwagandha Reduces cortisol and feeling of anxiety. Many people find this herb calming. It may also support thyroid function
Rhodiola (Rhodiola spp.) Several randomized, double-blind, placebo-controlled trials have supported the ability of standardized Rhodiola to enhance the body’s physical and mental work capacity in addition to improving productivity under stressful conditions. It is highly effective at helping with the psychological impact of stress, even enhancing physical and mental endurance
Theanine Increases focused (alpha) brain wave activity and reduces feeling of anxiety. Non-habit forming and works quickly within 30 minutes
GABA Calming neurotransmitter that prevents the overstimulation of the brain and nerves. Maybe also work via the gut-brain connection to produce feeling of calmness.

Invisible stressors

Although electromagnetic radiation is not a new phenomenon, the magnitude to which we are exposed to it has greatly increased recently. Electricity now surrounds us, and even if we did not use electrical devices, we would still be exposed to radio and satellite frequencies and electrical fields. Non-ionizing electromagnetic radiation comprises most of our daily exposure; however, we may be exposed to small amounts of ionizing radiation in our daily lives as well

as in medical facilities. One study found that exposure to cellular telephone non-ionizing radiation caused a 12% decrease in cortisol levels during a four-week exposure to the body. 

Another study found that both low and high levels of non-ionizing radiation from TV and radio broadcasting stations caused subjects to secrete higher levels of cortisol. Remember that both high and low levels of cortisol can negatively affect immunity. There continues to be controversial evidence related to the health effects of non-ionizing radiation, and its cumulative effects. Some experts are not warning of the damaging effects of 5G radiation with one of the key negative effects being a less responsive immune system. While we can’t totally avoid this invisible stressor, some precautions might be prudent. Be careful to limit your exposure to source of radiation, wifi and cellphone signals especially one hour before bed and while sleeping. 

In Summary – Manage Stress, Stay Healthy

Evidently, we are constantly encountering forms of unavoidable stress. Of course, there are ways to reduce stress. The most effective way to reduce stress is to remove or minimize the stressor. If this is not possible, the next best thing is to learn how to manage stressful situations. Behavioural and cognitive strategies, deep breathing, positive thinking, various therapies, keeping adequately hydrated with clean water, eating nutritious foods that are as close to their natural states as possible, taking dietary supplements, getting enough good quality sleep during optimal time periods, relaxing more often, doing enjoyable activities, and getting the right amount of the right kind of exercise are some techniques to manage stress. Managing stress, and hence cortisol release, may cost money, time, or certain lifestyle changes, but does any good thing come without a cost? And the price is worth the benefit!


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