
How Bright Light Therapy Improves Moods, Focus, and Sleep
Bright light therapy boosts moods and more—plus, it may increase brain volume. Discover how this simple treatment improves mental health.
What’s stressing you out? If you’re like most Americans, you deal with numerous stressors in life, from personal hardships to world events. In fact, a certain level of stress is normal and natural—it can even be helpful.
But studies show that stress is problematic when it’s prolonged and persistent. Chronic stress takes a devastating toll on the brain, and therefore mental health. Even physical health can decline as a result of high stress levels.
In this blog, you’ll learn more about the connections between chronic stress and brain health, symptoms to watch out for, and how to reduce stress in your everyday life for improved well-being and longevity.
Stress responses are the body’s finely tuned, intelligent ways of facing and overcoming difficulties. But chronic stress is harmful to both mental and physical health.
The American Psychiatric Association’s 2024 mental health poll found that 43% of American adults are feeling more anxiety than the previous year. And they were most likely to cite stress as the #1 factor affecting their mental health, with 53% saying it plays a role.
Stressful events, of course, are unavoidable. Difficulties like the death of a loved one, coping with an illness, changing jobs, or relationship struggles can generate stress. So can positive changes, like welcoming a new child or retirement.
Fortunately, some degree of stress can benefit the brain. A 2022 study found an association between low to moderate stress levels and increased neural activation related to working memory. This improves working memory performance, which may help protect against severe stress. Furthermore, coping with stress makes humans better equipped to handle future stressors.
However, this study also found that high stress levels were found to be harmful to the working memory. And the benefits of low to moderate stress were more pronounced among those who possessed certain resources. These include self-belief, social connections like friendship, and enjoying meaning and purpose in life.
But without helpful resources to handle stress, it can take a serious toll. And when stressors pile up—either in a short amount of time or over many years—they can be damaging. For example, those who faced multiple traumas as children may be at greater risk for succumbing to stressors or mental illness later in life.
Some mental health conditions associated with stress include:
An acute stressor—for example, being attacked—kicks off a complex chain reaction in the body. The sympathetic nervous system is activated, which creates a stress response. In the brain, the amygdala (which plays a role in emotions and fear) signals the hypothalamus, which controls brain chemicals, as well as the pituitary gland.
The adrenal glands then generate chemicals such as cortisol (often called the stress hormone) and adrenaline. Meanwhile, the frontal lobes—involved in executive functions like judgment, decision making, and rational thinking—decrease in activity as the amygdala takes over. We recognize this process as the fight-or-flight response.
Stress responses are the body’s finely tuned, intelligent ways of facing and overcoming difficulties. But if stressors or trauma are frequent or last over time, the stress response can feel “stuck” in place. Chronic stress can negatively impact the immune system and lead to numerous other physical, psychological, cognitive, and behavioral symptoms.
For example, studies have found that when cortisol production is excessive, the body is more susceptible to neurodegenerative diseases, such as Alzheimer’s and Parkinson’s. Neuroinflammation, chronic pain, and mental health conditions like major depressive disorder are also possible complications.
Meanwhile, persistent feelings of anxiety, panic, hypervigilance, or restlessness can contribute to sleep issues, brain fog, or exhaustion. Some individuals then self-medicate with harmful coping strategies, like using drugs (including alcohol), smoking, or nail biting.
Ultimately, chronic stress slowly erodes the body and brain over time. Additional symptoms of chronic stress can include:
Multiple studies have examined the effects of long-term stress on the brain. A 2017 article in the journal Chronic Stress pointed to various stress-induced brain changes:
In 2018, another study noted that chronic stress has been linked to reduced volume of the hippocampus. Authors added that “chronic stress can modulate volumes of both the amygdala and frontal cortex, suggesting neurotoxic effects of stress hormones on the brain.”
And a 2023 study examining the neurocognitive effects of stress reported cellular-level changes, like neurodegeneration and alterations in the plasticity of synapses in the hippocampus. Stress has also been found to impair learning and memory for cognition-related tasks while facilitating emotion-based fear responses.
Fortunately, you can bring your body back to a calmer state after a threat has passed, or to simply reduce stress levels overall. Here are some strategies to try:
have been widely studied and acclaimed for their positive effects on stress. For example, one study of more than 400,000 people who participated in a six-week mindfulness course reported lower levels of stress and better work performance. Mindfulness can also incorporate movement (such as yoga) and/or diaphragmatic breathing techniques.
helps boost mood and improves depression and anxiety disorders. It stimulates feel-good chemicals, such as endorphins, and creates positive ripple effects, like promoting sleep and healthier dietary choices. Moreover, exercise helps build emotional resilience to better cope with future stressors.
networks is beneficial for the brain and mental health. The COVID-19 pandemic illustrated how social isolation can negatively impact health, increasing the risk of cognitive decline, psychiatric disorders, and more. In addition to connecting with friends and family, joining support groups and seeking therapy can be effective for reducing stress.
has been shown in numerous studies to boost well-being and lower stress. A 2018 study evaluated the effects of positive affect journaling (writing about the positives in life) among those with elevated anxiety. After just 1-2 months of practice, participants reported less mental distress, increased well-being, reduced depressive symptoms and anxiety, and greater resilience.
With its far-reaching impacts on the brain and body, chronic stress is worth preventing. While some stress is a normal part of life, it can prove dangerous or even deadly if it’s not kept in check. Take steps today to reduce your stress levels and enjoy the full-body benefits it offers—in the moment and, with consistent practice, for years to come.
American Psychiatric Association, American Adults Express Increasing Anxiousness in Annual Poll; Stress and Sleep are Key Factors Impacting Mental Health, https://www.psychiatry.org/news-room/news-releases/annual-poll-adults-express-increasing-anxiousness
Assaf Oshri, Zehua Cui, Max M. Owens, Cory A. Carvalho, Lawrence Sweet, Low-to-moderate level of perceived stress strengthens working memory: Testing the hormesis hypothesis through neural activation, Neuropsychologia, Volume 176, 2022, 108354, ISSN 0028-3932, https://doi.org/10.1016/j.neuropsychologia.2022.108354.(https://www.sciencedirect.com/science/article/pii/S0028393222002135)
Knezevic E, Nenic K, Milanovic V, Knezevic NN. The Role of Cortisol in Chronic Stress, Neurodegenerative Diseases, and Psychological Disorders. Cells. 2023 Nov 29;12(23):2726. doi: 10.3390/cells12232726. PMID: 38067154; PMCID: PMC10706127.
McEwen BS. Neurobiological and Systemic Effects of Chronic Stress. Chronic Stress (Thousand Oaks). 2017 Jan-Dec;1:2470547017692328. doi: 10.1177/2470547017692328. Epub 2017 Apr 10. PMID: 28856337; PMCID: PMC5573220.
Kim, E.J., Kim, J.J. Neurocognitive effects of stress: a metaparadigm perspective. Mol Psychiatry 28, 2750–2763 (2023). https://doi.org/10.1038/s41380-023-01986-4
Bartlett Larissa , Buscot Marie-Jeanne , Bindoff Aidan , Chambers Richard , Hassed Craig. Mindfulness Is Associated With Lower Stress and Higher Work Engagement in a Large Sample of MOOC Participants, Frontiers in Psychology, Vol. 12, 2021, https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2021.724126, DOI=10.3389/fpsyg.2021.724126, ISSN=1664-1078
Childs E, de Wit H. Regular exercise is associated with emotional resilience to acute stress in healthy adults. Front Physiol. 2014 May 1;5:161. doi: 10.3389/fphys.2014.00161. PMID: 24822048; PMCID: PMC4013452. \
Smyth JM, Johnson JA, Auer BJ, Lehman E, Talamo G, Sciamanna CN. Online Positive Affect Journaling in the Improvement of Mental Distress and Well-Being in General Medical Patients With Elevated Anxiety Symptoms: A Preliminary Randomized Controlled Trial. JMIR Ment Health. 2018 Dec 10;5(4):e11290. doi: 10.2196/11290. PMID: 30530460; PMCID: PMC6305886.
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