The link between stress and brain health

The effects of stress are well reported in relation to many health conditions, for example, cardiovascular health. What has received less media attention are the effects of stress on brain health.

Stress begins in the brain. As information comes in through our ears and eyes it travels to several parts of the brain. When an individual perceives stress (anything from pain to a maths test) the body interprets and processes the threat in an area of the brain called the amygdala. From there the amygdala switches on two other systems – the hormone system and a branch of the nervous system called the sympathetic nervous system.

Stress-mediated effects on brain function can be beneficial or detrimental, depending on the type of stressor and the duration of exposure to the stressor. Chronic stress may result in changes to neuronal (ie nerve) structure and function and also neuronal death, thus it may accelerate the process of brain degeneration that eventually leads to dementia, including Alzheimer’s disease.

In one study, there was a 65% increased risk of developing dementia from high stress levels. This blog discusses the effects of chronic stress on the brain and suggests practical ways to manage and reduce stress.

What causes stress?

We are all familiar with the causes of stress – work, relationships, money, house moves, exams and social gatherings for example. Less obvious but also important are anti-nutrients (caffeine, drugs, alcohol), poor diet, food intolerances, additives, toxins, infections, poor sleep, dehydration, pain, as well as thoughts, beliefs and perceptions. In short – 21st Century Living!

The hypothalamic-pituitary-adrenal axis (HPA axis) and the stress hormone cortisol

Levels of the stress hormone cortisol naturally follow a circadian rhythm, rising rapidly after waking, falling during the day, rising in late afternoon before dropping to lowest levels in the middle of the night.

Increased production of cortisol occurs during stress: the hypothalamus responds to stress by releasing CRF (corticotrophin releasing factor) which stimulates the pituitary to release ACTH (adrenocorticotrophic hormone). One of the actions of ACTH is to stimulate the adrenal cortex to release cortisol.

Increased production of cortisol has a number of actions including increasing the availability of glucose in order to ready the body for action, in other words, to facilitate the ‘fight or flight’ response. As well as increasing the body’s readiness for action, cortisol suppresses processes that are not needed immediately e.g the highly demanding immune system.

This is why stress can increase susceptibility to coughs / colds and other infections. Once the challenge has passed, the human body should release and relax. Of course, in today’s environment, there is often no recovery, just ongoing stimulation of the stress response.

 Detrimental effects of cortisol on brain health

Increases in plasma cortisol levels have been reported in patients with Alzheimer’s disease and a correlation has been found between increases in 24 h cortisol levels and the severity of cognitive defects in Alzheimer’s. Deficits in learning and memory have been reported in rodents after chronic stress. Chronic, ie long-lasting, increases in cortisol secretion have been found to:

  • Induce neuronal loss in the area of the brain important for short-term memory, the hippocampus. One of the functions of the hippocampus is to inhibit over-activity of the hypothalamic-pituitary-adrenal axis (HPA axis) and so stress could initiate a vicious cycle of HPA over-activity and neuronal loss in the hippocampus.
  • Stress suppresses neurogenesis and reduces the expression of Brain Derived Neurotrophic Factor (BDNF) – a growth factor produced in the brain, sometimes called ‘miracle-gro’ for the brain.
  • Stress increases inflammation and studies in mice suggest that stress hormones may increase the production and toxicity of beta-amyloid. It is also possible stress increases tau tangle formation. Both beta-amyloid and tau tangles are part of the pathology of Alzheimer’s.
  • Stress can cause high blood pressure and other vascular factors that are related to both Alzheimer’s disease and vascular dementia.

Stress can also have detrimental effects on brain function by:

  • Increasing blood sugar. This can lead to an increase in the production of advanced glycation end products (AGEs) which cause damage to cellular proteins, lipids and DNA. High blood sugar can lead to insulin resistance and the brain may become insulin resistant years before other tissues in the body. Insulin resistance can result in brain cells being ‘starved’ of fuel because glucose cannot effectively enter cells.
  • Affecting sleep and reducing both sleep quantity and sleep quality. Sleep is important for cell repair and regeneration and beta-amyloid clearance. Reduced sleep can impair brain function. It can also increase the hunger hormone ghrelin, making us hungrier the following day and leading to poor food choices and an increased craving for sugary and starchy foods.
  • Affecting gut health – cortisol suppresses gut immunity with the consequence of increased growth of undesirable gut microbes at the expense of the beneficial gut microbes. This imbalance in gut flora can contribute to the development of leaky gut; in turn leaky gut contributes to systemic inflammation in the body and ultimately brain inflammation. LPS (lipopolysaccharide) produced by some types of undesirable gut bacteria has been found in beta-amyloid and there is a suggestion that LPS triggers the production of increased beta-amyloid.

When experiencing stress, it can be difficult to make good lifestyle and diet choices – sugary foods may be used as a ‘pick me up’, there may be no time to cook, alcohol is used to relax, bedtimes are pushed later and we rob time from sleep; then stimulants such as coffee are used after a poor night’s sleep to get going in the morning.

This cycle can be broken, how can we do it?

The Upside of Stress

Firstly, rather than always focusing on the negatives of stress, perhaps we should also focus on the positives. Kelly McGonigal, a health psychologist, in her book ‘The Upside to Stress’ discusses how our belief about stress is a crucial factor in how we are affected by it. A 1998 study changed her perspective on stress and led to further exploration. In 1998, 30,000 adults in the US were asked how much stress they’d experienced in the past year and whether they believed stress was harmful to their health. Eight years later the researchers looked to see how many of the 30,000 had died.

The results showed high levels of stress increased risk of dying by 43%, but this was only related to people who also thought that stress was harming their health. The study concluded that it wasn’t stress alone that was killing people but a combination of stress and the belief that stress was harmful. A different message from what we are used to but an interesting one.

How to manage stress

Much has been written on mindfulness, yoga, tai chi, exercise and their benefits to manage stress and there are many excellent resources available. Other techniques that you can start using straight away:


Studies have shown that watching wildlife (eg birds), spending time in nature, or even watching natural history programmes can reduce stress and anxiety and improve mood. So try swapping high tension drama for David Attenborough on the television.


Certain types of breathing can stimulate ‘the relaxation response’. For example, breathing in through your nose for approx. 7 seconds, pausing, and then breathing out slowly through your mouth for approx. 11 seconds. Try 2 or 3 breaths to start with and build-up to repeating 12 times. Repeat at least once daily. While carrying out this exercise you can try visualising a word such as ‘CALM’ or a relaxing scene.

Happiness & gratitude journal

This relates to the fact that our thoughts, perceptions and beliefs can trigger the stress response or equally the relaxation response. A gratitude and happiness journal is a notebook that you can keep next to your bed and complete daily (only takes a couple of minutes). The key to this exercise is finding some positives from the day. It is particularly beneficial to do at bedtime as it will give a positive feeling to the end of the day as you get ready for sleep; reflecting and ‘framing’ your day in a positive way (even the worst days can be ‘reframed’).

So each night find and write down at least 3 positives from the day, they can be small eg it was a sunny day. This technique has been shown to increase happiness (and by association reduce stress levels) within 7 days!


Our emotional response to stress is important. Sometimes easier said than done, but try taking a “whatever” approach to stressful situations. Shrug and breathe out deeply as you say this. It works!

Eat dark chocolate

Dark chocolate (70% or 85% cocoa) can have a positive impact on cortisol levels. A Swiss study found that “the daily consumption of dark chocolate resulted in a significant modification of the metabolism of healthy and free living human volunteers with potential long-term consequences on human health within only 2 weeks treatment,” the researchers wrote, “this was observable through the reduction of levels of stress-associated hormones and normalisation of the systemic stress metabolic signatures.”

Blood sugar balance

Blood sugar crashes cause the release of cortisol, which helps raise blood sugar levels again when they crash. However, if poor diet is causing blood sugar crashes through the day then levels cortisol will be elevated for long periods – contributing to increased feelings of stress. Feelings of stress can cause cravings for high sugar foods, leading to a vicious cycle. Stress can be supported by eating a diet that keeps blood sugar balanced and which provides adequate nutrients for the adrenal glands, involved in the stress response. This is a low sugar diet, high in vegetables with adequate protein and healthy fats.

 Specific nutrients

There are a number of nutrients that are important for helping the body cope with stress – some nutrients are calming such as magnesium and pantothenic acid, others support the adrenal glands that produce the stress hormones, eg B vitamins, vitamin C (pantothenic acid is also used by adrenal glands). Foods that are good sources of magnesium and B vitamins include nuts and green leafy vegetables. Vitamin C – again, green leafy vegetables and fruit (but choose low sugar varieties).

There are also herbs that people use to help cope with stress. For example, ashwaganda is a herb that is used in Ayurvedic medicine to support sleep and calmness. Siberian gingseng and liquorice are often used in formulas to support the adrenal glands (glands that produce the stress hormones) and are often used when stress has been going on for some time and the person has started to feel fatigued (unremitting long term stress can lead to ‘burn out’ and exhaustion).

Teas – chamomile tea has calming properties and, of course, black tea contains L-theanine which increases levels of brain calming chemicals – may be why “a nice cup of tea” is offered as comfort.

The Action Against Alzheimer’s programme

For further support in maintaining good brain health, you may be interested in the Action Against Alzheimer’s Programme. This is for people BEFORE they develop dementia; it is a workshop programme based on the diet and lifestyle elements of the Bredesen Protocol™. The Action Against Alzheimer’s programme is being delivered by Cytoplan Licensed Nutritional Therapists to small groups of the general public through a series of 8 workshops. The workshops are designed to help people engage with each aspect of the programme and understand what they need to do to optimise brain function, thus the workshops cover: Nutrition, Gut Health, Stress, Sleep; Exercise & Brain Training.

If you would like to find a Licensed Action Against Alzheimer’s practitioner near you, then please contact me, and I will send you details when we have someone in your area.

If you have any questions regarding the topics that have been raised, or any other health matters please do contact me (Clare) by phone or email at any time., 01684 310099

The Cytoplan editorial team: Clare Daley and Joseph Forsyth

Relevant Cytoplan Supplements

Ashwagandha – used in traditional Ayurvedic medicine as an adaptogen by people experiencing stress and insomnia.

Biofood Magnesium – magnesium is used by the adrenal glands. It provides a role in contributing to normal psychological and muscle function (it is a muscle relaxant). If being used to support sleep it should be taken at bedtime.

Pantothenic acid – the adrenals use large amounts of B5 when responding to stress. B5 can be particularly useful if stress is accompanied by tiredness/ fatigue and/or anxiety.

Cherry C – used by the adrenal glands. Roles including contributing to normal psychological function and reduction of tiredness and fatigue.

Blood Glucose Support – contains nutrients involved in blood sugar control such as chromium and others.

Acidophilus Plus – live bacteria. Stress can create an imbalance in gut bacteria which can result in IBS-type or other gut symptoms, more frequent coughs/colds or worsened allergies.

5-HTP Plus – 5-HTP is the precursor to the ‘happy hormone’ serotonin. Serotonin is the precursor to melatonin (the sleep hormone). 5-HTP should not be taken alongside anti-depressants.

P5P Extra –  the B complex vitamins are involved in the stress response and energy production. May be useful if stress is resulting in fatigue.

Adrenal Support – a combination of vitamins and minerals, herbs and plant extracts including pantothenic acid, selenium, chromium, kelp, Siberian gingseng, suma root, Chinese red gingseng, tienchi root and licorice extract.

Siberian Ginseng – a herb which has traditional use as a harmony remedy – these were used by traditional healers in the Orient.


Anderson D C (2008) – Assessment and nutraceutical management of stress-induced adrenal dysfunction. Integrative Medicine, 7, 5

Dong H & Csernansky J G (2009) – Effects of Stress and Stress Hormones on Amyloid-β Protein and Plaque Deposition, J Alzheimers Dis, 18, 2, 459-469

Epel E et al (2004) – Accelerated telomere shortening in response to life stress Proc Natl Acad Sci, 101(49):17312-5.

Ishida R, Okada M – (2006) – Effects of a firm purpose in life on anxiety and sympathetic nervous activity caused by emotional stress, Stress & Health, 22, 4, 275-281

Johansson L et al (2010) –  Midlife psychological stress and dementia: a 35-year longitudinal population study Brain, 133, 2217-2224

Martin F P J et al (2009) – Metabolic Effects of Dark Chocolate Consumption on Energy, Gut Microbiota, and Stress-Related Metabolism in Free-Living Subjects. Journal of Proteome Research, 8, 12, 5568-5579

McGonigal K (2015) – The Upside to Stress. Vermilion

Last updated on 24th May 2017 by tarryn


3 thoughts on “The link between stress and brain health

  1. very helpful encapsulates all the snippets I have gleaned from elsewhere. Not sure how to stop worrying that stress is affecting my brain, though !

    I do seem to already be taking most of the suggested supplements, but with no discernable benefit. [perhaps I would be worse without them]

    One thing not mentioned is something I wish I had accesss to – quiet companionship. I react to/mirror whoever I am with, and as I am with my disabled Asperger husband 24/7 I am turning into a version of him = short tempered, irritable. Can anyone suggest a way of getting through, when his mind is always somehwere else and he fails to take in what I am saying – leading to more frustration?

    1. Thank you for your comment on our blog. I am not sure what suggestions to make in relation to your difficulties in communicating with your husband.

      You do also mention a desire for quiet companionship. Have you had a look on You can find local groups with shared interests – there are a huge range of meet-ups, activities and events included on the site. Many are free.

      Secondly as you are probably already aware, there are carer support services available that can be accessed via your GP.

      If you would like some specific diet and supplement advice, we do have a free health questionnaire service – if you complete and return a health questionnaire we will send you some written diet and supplement suggestions to support your specific health concerns.

      All the best,

  2. This was a great article for me because recently I’ve kept forgetting things, eg putting something on the stove to cook and just walking away and forgetting about it – I’ve done it several times recently – and I’ve been worried about dementia, but friends have said it’s because I’ve had so much stress to deal with recently that my brain is on overload.
    I can’t remember names any more, but I think that is part of ageing. I have had a massive amount of stress since mid-December and have also been ill with sinus and cold problems since then, but they are now clearing up, thank goodness as it’s now the end of March. I am 69, active, (I have three dogs) and look after other peoples’ dogs as well, so keep busy. I also sing in two choirs, which I believe is good for the brain, as well as being great company and gives a huge amount of happiness.

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