How does stress affect your body?

Find out more about why and how high-stress levels can have a negative effect on your health.

Stress is the body’s way of responding to a demand or threat. In the right circumstances, stress can help you to stay focused, energetic, and alert. It helps you keep on your toes at work, drives you to study for an exam, or gives you extra strength to defend yourself.

Beyond a certain point, constant day-to-day pressures can lead to unhelpful levels of stress that can cause damage to your health, mood, productivity, relationships, and quality of life.

You may be sitting at your desk and the stress response is triggered by yet another task on the never-ending to-do list. Instead of responding to what our bodies instinctively tell us to do (run away), we sit there, and the symptoms of stress take over.

Many of us find that our stress response is triggered too often, and we enter a constant state of stress, known as chronic stress. Chronic stress can affect how you feel, think, behave, and even how your body works.

Effects of chronic stress

If you get stressed out frequently, it can start to take a toll on your body. Chronic stress can disrupt nearly every system in your body, including the following:

  1. Insomnia

Insomnia is when you have difficulty getting to sleep or staying asleep for long enough to feel refreshed in the morning [1]. It’s a common problem and roughly affects one in three people in the UK.

You may struggle to sleep if you are lying awake worrying about issues with money, housing, or work. If you are experiencing any problems with sleeping, Mind and the NHS, have some great tips on how to relax and get a better night’s sleep.  

  1. Loss of appetite

When the stress response is triggered, your body releases stress hormones. Research suggests that one of the hormones released, the corticotropin-releasing factor (CRF), affects the digestive system and can suppress the appetite [2].

Cortisol increases the secretion of stomach acid to help speed up digestion, making it easier to run away. However, this can also cause constipation and indigestion, which may also cause a loss of appetite.

Eating small meals more frequently and making sure what you eat is rich in nutrients can help if you’re experiencing a loss of appetite.

Food to eat when you have lost your appetite [3]:

  • Soup
  • Meal-replacement shakes
  • Fruit-filled smoothies

Seek advice from your GP if you have a loss of appetite for two weeks or more or if you are losing weight rapidly.

You can also find ways to manage your stress in our ten ways to de-stress section.

  1. Impaired regulation of blood sugar

When your body enters the stress response, it releases the hormone cortisol. Cortisol is responsible for increasing sugars (glucose) in the bloodstream [4].  

When the body experiences high levels of chronic stress, it releases more cortisol. High levels of cortisol can cause the body to decrease insulin secretion [5].

Insulin helps bring sugar into the cells from the bloodstream, where it’s used for energy. Without the proper release of insulin, sugar can remain in the bloodstream, and blood sugar levels can become imbalanced.

Some research indicates that prolonged high levels of cortisol in your system will leave you with a higher risk of developing diabetes [6].

  1. Migraines

Migraines are moderate or severe headaches felt as a throbbing pain on one side of the head. It is a common health condition, affecting around one in five women and around one in fifteen men [7].

Research has found that one of the main triggers of migraines is stress [8]. A 2014 study showed that reducing stress levels can reduce the chance of having a migraine the following day [9].

  1. High blood pressure

It is normal for your blood pressure to increase for short periods when feeling stressed. Adrenaline can make your heart beat faster, and your blood pressure rise. Once the stress response has resolved, your blood pressure should return to normal.

However, chronic stress can cause unhealthy lifestyle changes such as eating unhealthily and drinking too much alcohol, which can cause long-term high blood pressure.

High blood pressure can be detrimental to your health and damage major organs and arteries over time. It is best to try and get your blood pressure back within a normal range.

Lower your blood pressure by:

  • Eating a healthy diet
  • Reducing alcohol intake
  • Exercising regularly

Find out more about your blood pressure on the NHS website.

  1. Impaired immune system

Chronic stress can affect the components of the immune system in a potentially detrimental way [10].

When your body creates cortisol (the stress hormone) it can lower the number of lymphocytes present in the blood, interfering with normal white blood cell communication. If your white blood cells are not working correctly, it will affect how your immune system fights viruses.

Keep your stress levels low to help your immune system work well and keep those common colds at bay.

See our how to reduce your risk of flu blog for more information on steps you can take to reduce viruses.

  1. Increased risk of cardiovascular diseases

Stress alone won’t cause heart and circulatory disease [11]. However, similarly to blood pressure, your risk of cardiovascular diseases increases with unhealthy lifestyle changes such as smoking, high sugar intake, and drinking too much alcohol.

Eating a tub of ice cream, drinking a bottle of wine, or smoking a pack of cigarettes may make you feel less stressed in the short term, but if you continue for too long, then it can damage your heart health.

If you are struggling with stress, the NHS’s Mind Plan Programme can help you better your mental health. The Mind Plan gives you tips to help you to de-stress and get you feeling positive and energised.

Are your cortisol levels affecting your health and wellbeing?

If you’re unsure whether your cortisol levels could be affecting your wellbeing, our Cortisol Saliva Stress Test can help.

These simple at-home saliva tests can measure your cortisol levels, helping you to understand whether your stress levels are having a negative impact on your health and wellbeing.


  1. 2021. Insomnia causes and treatments. [online] Available at: <> [Accessed 21 December 2021].
  2. Ans, A., Anjum, I., Satija, V., Inayat, A., Asghar, Z., Akram, I. and Shrestha, B., 2018. Neurohormonal Regulation of Appetite and its Relationship with Stress: A Mini Literature Review. Cureus,.
  3. 2021. Does anxiety cause a loss of appetite?. [online] Available at: <> [Accessed 21 December 2021].
  4. Mayo Clinic. 2021. Chronic stress puts your health at risk. [online] Available at: <,fight%2Dor%2Dflight%20situation> [Accessed 21 December 2021].
  5. Kamba, A., Daimon, M., Murakami, H., Otaka, H., Matsuki, K., Sato, E., Tanabe, J., Takayasu, S., Matsuhashi, Y., Yanagimachi, M., Terui, K., Kageyama, K., Tokuda, I., Takahashi, I. and Nakaji, S., 2016. Association between Higher Serum Cortisol Levels and Decreased Insulin Secretion in a General Population. PLOS ONE, 11(11), p.e0166077.
  6. Kamba, A., Daimon, M., Murakami, H., Otaka, H., Matsuki, K., Sato, E., Tanabe, J., Takayasu, S., Matsuhashi, Y., Yanagimachi, M., Terui, K., Kageyama, K., Tokuda, I., Takahashi, I. and Nakaji, S., 2016. Association between Higher Serum Cortisol Levels and Decreased Insulin Secretion in a General Population. PLOS ONE, 11(11), p.e0166077.
  7. 2021. Migraine. [online] Available at: <> [Accessed 21 December 2021].
  8. Maleki, N., Becerra, L. and Borsook, D., 2012. Migraine: Maladaptive Brain Responses to Stress. Headache: The Journal of Head and Face Pain, 52, pp.102-106.
  9. Lipton, R., Buse, D., Hall, C., Tennen, H., DeFreitas, T., Borkowski, T., Grosberg, B. and Haut, S., 2014. Reduction in perceived stress as a migraine trigger: Testing the "let-down headache" hypothesis. Neurology, 82(16), pp.1395-1401.
  10. Segerstrom, S. and Miller, G., 2004. Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry. Psychological Bulletin, 130(4), pp.601-630.
  11. 2021. Stress. [online] Available at: <> [Accessed 21 December 2021].

Related tests

Cortisol Saliva Stress Test

Our popular cortisol saliva test helps you understand your stress levels and adrenal function by testing your cortisol levels 4 times over the course of a day

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