Stress' impact on immunity and inflammation

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Stress can be difficult to avoid in periods of life but increased stress can weaken immune functions.

Ongoing stress triggers high levels of cortisol, a steroid hormone. A weak immune system raises the risk of infections caused by viruses and other pathogens.

Excess cortisol diminishes immune functions and has been shown to increase disease risk while shortening human lifespans. (1-17)

A 2019 study found that anticipating stress the next day is associated with elevated cortisol soon after waking up in the morning. (18) Human studies indicate that specific plant extracts can reduce cortisol levels and inhibit its destructive effects. (19-24)

The stress hormon cortisol 

Cortisol is one of the body’s main stress hormones. During stressful times, the adrenal glands release it as part of the “fight-or-flight” response. (26) Necessary for life-or-death situations, cortisol directs a complex series of hormonal and physiological changes that support either fleeing to safety or fighting off the threat. (27,28)

Cortisol boosts muscle tension, blood sugar, heartbeat, tissue-repair substances, and mental focus. At the same time, cortisol turns down non-urgent processes such as immune functions, along with the digestive and reproductive systems. (29)

When the stressful threat has passed, cortisol is supposed to return to normal “balanced” levels. When stressors are almost always present cortisol remains “turned on.” Its continuing high presence in the blood adversely affects critical functions of the body and brain. (30)

Danger of elevated cortisol

Stress results in a decrease in levels of lymphocytes. These immune cells are used to kill viruses and other invaders. (31,32) Lymphocyte counts are often reduced when one is fighting a viral infection. (33-35) 

Even if it’s just for a few days, social isolation and loneliness also weaken immunityOlder individuals are more susceptible to stress and to stress-induced immune damage. (36-37)

Long-term overexposure to excess cortisol disrupts almost all body processes, increasing risk for health problems that include: (1-17,38)

  • Immune impairment
  • Cardiovascular disease
  • Diabetes
  • Osteoporosis
  • Gastrointestinal problems
  • Obesity
  • Neurodegeneration, including Alzheimer’s disease
  • Anxiety, depression, and insomnia

Most worrisome, chronically elevated cortisol is linked to increased mortality risk. A large study of people over age 65 found that men with high cortisol levels were 63% more likely to die than those with lower levels.

Women with elevated cortisol were 82% more likely to die than those with low levels. (5) And those with high urinary cortisol had a five-fold increased risk of death from cardiovascular disease. (3)

Higher cortisol is also associated with shortening of telomeres, the stretches of DNA that cap the ends of chromosomes. (39,40) As telomeres shorten, the cells that bear them get closer to the ends of their lives, aging the tissues and organs in which they dwell.

It’s impossible to avoid all stress. But scientists have demonstrated that natural compounds can lower excess cortisol levels.  (41)

How can you measure your stress level?

Stress can become so constant that you don’t even notice how stressed you are. A cortisol blood test allows you to find out whether your levels are elevated and by how much. If they’re high, that’s a sign of ongoing stress.

Lifestyle changes like exercise, and eating a healthy diet can bring this level down. 

Regular use of safe, plant compounds also lowers elevated cortisol and can prevent the immune-weakening effects of stress.

A follow-up cortisol test will show whether your efforts have been successful or need to be intensified. (41)

Help for stress management & immunity


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