Some brain-related stress symptoms, like memory loss, brain fog, anxiety, and worry, will be obvious to you.
But most of the effects of stress discussed below are “behind the scenes.”
When stress becomes chronic, it changes your brain down to the level of your DNA.
You won’t notice these changes while they’re happening, but you will notice the side effects … eventually.
- Stress Creates Free Radicals That Kill Brain Cells
Cortisol creates a surplus of the neurotransmitter glutamate.
While glutamate is a necessary and important brain chemical, in excess it turns against your brain and becomes a neurotoxin.
Glutamate creates free radicals — unattached oxygen molecules — that attack brain cells in much the same way that oxygen attacks metal, causing it to rust.
Free radicals actually punch holes in brain cell walls, causing them to rupture and die.
Stress also indirectly contributes to other lifestyle habits that create more free radicals.
If stress causes you to lose sleep, eat junk food, drink too much alcohol, or smoke cigarettes to cope, know that these unhealthy habits are adding to your free radical load.
- Stress Makes You Forgetful and Emotional
Memory problems may be one of the first signs of stress that you’ll notice.
Misplaced keys and forgotten appointments have you scrambling, further adding to your stress.
If you find that all this stress is making you more emotional too, there’s a physiological reason for this.
Studies show that when you’re stressed, electrical signals in the brain associated with factual memories weaken, while areas in the brain associated with emotions strengthen.
- Stress Creates a Vicious Cycle of Fear and Anxiety
Stress actually fortifies an area of your brain called the amygdala.
This is your brain’s fear center.
Stress increases the size, activity level, and number of neural connections in this part of the brain.
This makes you more fearful, causing a vicious cycle of even more fear and stress.
- Stress Halts the Production of New Brain Cells
Every day you lose brain cells, but every day also you have the opportunity to create new ones.
Brain-derived neurotrophic factor (BDNF) is a protein that’s integral in keeping existing brain cells healthy and in stimulating new brain cell formation.
It’s often likened to fertilizer for the brain.
BDNF can offset the negative effects of stress on the brain.
But cortisol halts the production of BDNF, resulting in fewer new brain cells being formed.
Lowered levels of BDNF are associated with brain-related conditions including depression, obsessive-compulsive disorder, schizophrenia, dementia, and Alzheimer’s disease.
- Stress Depletes Critical Neurotransmitters
Your brain cells communicate via chemicals called neurotransmitters.
Constant stress reduces levels of critical neurotransmitters, especially serotonin and dopamine.
Low levels of either of these neurotransmitters can leave you depressed and more prone to addictions.
Serotonin is dubbed the “happy molecule.”
It plays a large role in mood, learning, appetite control, and sleep.
Women low in serotonin are prone to depression, anxiety, and binge eating.
Men, on the other hand, are more prone to alcoholism, ADHD, and impulse control disorders.
Dopamine is known as the “motivation molecule.”
It’s in charge of your pleasure-reward system.
Too little dopamine can leave you unfocused, unmotivated, lethargic, and depressed.
People low in this brain chemical often use caffeine, sugar, alcohol, and illicit drugs to temporarily boost their dopamine levels.
Serotonin-based depression is characterized by anxiety and irritability, while dopamine-based depression expresses itself as lethargy and lack of enjoyment of life.
- Stress Puts You at Greater Risk for Mental Illnesses of All Kinds
Recent research has discovered physical differences in the brains of people with stress disorders. (25)
Chronic stress puts you at increased risk for developing a variety of mental illnesses, including anxiety and panic disorders, depression, PTSD, schizophrenia, bipolar disorder, drug addiction, and alcoholism.
- Stress Makes You Stupid
Stress can cause your brain to seize up at the worst possible times — exams, job interviews, and public speaking come to mind.
This is actually a survival mechanism.
If you’re faced with a life and death situation, instinct and subconscious impulse overwhelm rational thought and reasoning.
This might keep you from being killed in an encounter with a tiger, but, in modern life, this is rarely helpful.
Stress impairs your memory and makes you bad at making decisions.
It negatively impacts virtually every cognitive skill you rely on to get through the day, including your ability to pay attention, remember, solve problems, make decisions, and think critically.
- Stress Shrinks Your Brain
Stress can measurably shrink your brain.
Cortisol can kill, shrink, and stop the generation of new neurons in the hippocampus, the part of your brain that stores memories.
The hippocampus is critical for learning, memory and emotional regulation, as well as shutting off the stress response after a stressful event is over.
Stress also shrinks the prefrontal cortex.
This negatively affects decision making, working memory, and impulse control.
- Stress Lets Toxins into Your Brain
Your brain is highly sensitive to toxins of every kind.
The blood-brain barrier is a group of highly specialized cells that act as your brain’s gatekeeper.
This semi-permeable filter protects the brain from harmful substances, while letting needed nutrients into the brain.
Stress makes the blood-brain barrier more permeable, in effect making it leaky.
This lets substances into the brain that you don’t want there — pathogens, heavy metals, chemicals, and neurotoxins of all kinds.
Clearly, this is not desirable.
- Stress Increases Your Risk of Dementia and Alzheimer’s
One of the most worrying effects of stress on the brain is that it increases your risk for dementia and Alzheimer’s.
Being diagnosed with Alzheimer’s disease is now the #1 health fear of American adults.
Alzheimer’s is also the sixth leading cause of death.
One in three US seniors will die with Alzheimer’s or other forms of dementia.
And it’s the most expensive disease in the country.
There is no simple “magic bullet” to prevent Alzheimer’s.
Common sense advice includes eating a healthy diet low in sugar and high in brain-healthy fats, getting physical exercise, not smoking, staying mentally active, avoiding toxic metal exposure, and minimizing stress.
It’s been found that stress, particularly stress that occurs in midlife, increases your risk of Alzheimer’s.
Mid-life occurrence of anxiety, jealousy, and moodiness doubles your risk of developing Alzheimer’s.
Chronic stress and elevated cortisol contributes to dementia in the elderly and hastens its progression.
- Stress Causes Brain Cells to Commit Suicide
Stress leads to premature aging on a cellular level, causing cells in both your body and your brain to commit suicide prematurely.
To understand how this happens, we need to take a look at a part of your chromosomes called telomeres.
You may recall from high school biology that when a cell divides, it passes on the genetic material to the new cell via chromosomes.
Telomeres are protective endcaps on our chromosomes similar to the plastic tips on shoelaces.
Every time a cell divides, the telomeres get a little shorter.
When they reach a critically shortened length, they tell the cell to stop dividing, acting as a built-in suicide switch.
Subsequently, the cell dies.
Shortened telomeres lead to the atrophy of brain cells, while longer telomere length leads to the production of new brain cells.
Telomere length may be the most important indicator of biological age and disease risk. (43)
Some researchers believe it’s a better predictor of your risk for age-related diseases like Alzheimer’s, heart disease, diabetes, and cancer than conventional diagnostic tools.
- Stress Contributes to Brain Inflammation and Depression
A little-known fact is that the brain has its own immune system.
Special immune cells called microglia protect the brain and spinal cord from infections and toxins.
Unfortunately, a microglial cell has no on or off switch, so once it is activated, it creates inflammation for the rest of its lifespan.
Chronic stress is one of the factors that increases the risk of activating your microglia, thus producing brain inflammation.
It’s generally believed that depression is caused by serotonin deficiency, but there’s a growing body of evidence that brain inflammation may be the root cause of depression instead.
This theory is called the “cytokine model of depression.”
Activated microglia produce cytokines — proteins that turn on the inflammation response in the brain.
Cytokine production is linked to depression, including major depressive disorder and increased thoughts of suicide.
It’s also associated with anxiety, memory loss, and inability to concentrate, as well as some serious mental disorders such as schizophrenia, Parkinson’s, and Alzheimer’s.
Tags: brain health, clinical research, emotions, stress