The Relationship Between Stress and Diseases

Stress is linked to disease in two main ways: it can worsen existing conditions, and long-term or chronic stress can increase the risk of developing some diseases in the first place. The strongest evidence is for cardiovascular problems, mental health conditions, sleep disturbance, digestive issues, and immune-related effects. Stress activates the sympathetic nervous system and the HPA axis, which raises stress hormones such as cortisol and adrenaline. In the short term, that response helps you cope, but when it stays activated, it can disrupt nearly every system in the body. Chronic stress is associated with inflammation, immune dysregulation, and changes in blood pressure, heart rate, and metabolism.
 
Diseases most linked to stress:
Heart disease, heart attack, high blood pressure, and stroke;
Anxiety, depression, and other psychiatric disorders;
Digestive problems and stomach ulcers;
Sleep problems and impaired concentration or memory; and
Higher susceptibility to infections, including the common cold, in chronically stressed people.
 
One important pathway is inflammation. Stress can raise inflammatory activity, and chronic inflammation is tied to age-related diseases such as cardiovascular disease and type 2 diabetes. Stress can also affect behaviour, making sleep, exercise, eating, and substance use patterns less healthy, which adds to disease risk. In the relationship between stress and depression, these effects can overlap and amplify each other. While acute stress is not automatically harmful, it is part of normal adaptation. The bigger health risk comes from chronic, repeated, or intense stress that keeps the stress-response system switched on. That is why stress management can be a real part of disease prevention, not just comfort care.
 
Stress has the clearest and strongest disease link with heart disease and type 2 diabetes, while the evidence for causing cancer is much weaker and more mixed.
 
Heart disease
Chronic psychological stress is associated with higher rates of coronary heart disease, hypertension, stroke, and other cardiovascular outcomes. Large cohort and review data suggest the risk is especially notable when stress is long-lasting or tied to a diagnosed stress-related disorder. One summary of the evidence reported that people with high stress were about 27% more likely to develop heart disease or die from it.
 
Diabetes
Stress can raise cortisol and catecholamines, which can increase insulin needs and insulin resistance. This makes chronic stress a plausible contributor to type 2 diabetes risk, especially when it interacts with obesity, poor sleep, and reduced activity. The relationship is biologically credible and supported by reviews, but stress is usually one factor among several rather than a sole cause.
 
Cancer
The stress-cancer link is more controversial. A recent systematic review of prospective studies found no consistent evidence that psychological stress clearly increases cancer incidence, and the certainty of evidence was rated very low. Some older and mechanistic papers argue stress may influence tumor progression, immunity, and treatment response, but that is different from proving it causes cancer.
 
For heart disease and diabetes, chronic stress is best understood as a risk amplifier rather than a single direct cause. For cancer, stress may matter more for coping, immune function, and quality of life than for cancer initiation itself. Reducing chronic stress can therefore support overall health, even if it is not a guaranteed way to prevent any one disease.
 
References
 
Anate, M., Citro, M., Caputo, M., Pisanti, S. & Martinelli, R. (2020, October 1). Psychological Stress and Cancer: New Evidence of an Increasingly Strong Link. Translational Medicine @ UniSa

​Ajibewa, T.A., Kershaw, K.n., Carr, J.J., Terry, J.G., Gabriel, K.P. et al. (2023, December 23). Chronic Stress and Cardiovacular Events: Findings from the CARDIA Study. American Journal of Preventive Medicine.
 
Chu, B., Marwaha, K., Sanvictores, T., Awosika, A.O. & Ayers D. (2024, May 7). Physiology, Stress Reaction. National Library of Medicine.
 
Golden, S.H. (2007, November). A Review of the Evidence for a Neuroendocrine Link Between Stress, Depression and Diabetes Mellitus. John Hopkins University.
 
Jaremka, L.M., Lindgren, M.E. & Kiecolt-Glaser, J.K. (2013, February 14). Synergistic Relationships Among Stress, Depression, and Troubled Relationships: Insights from Psychoneuroimmunology. Depression & Anxiety.
 
Mayo Clinic Staff. (2023, August 1). Chronic Stress Puts Your Health at Risk. Mayo Clinic.
 
Pacheco, S.I.G., Petrova, D., Garrido, D., Catena, A., Perez-Esparza, B.M., et al. (2025, December 3). The Relationship Between Psychological Stress and Cancer Incidence: A Systematic Review and Meta-Analysis. Health Psychology Review.
 
Sharma, K., Akre, S., Chakole, S. & Wanjari, M.B. (2022, September 13). Stress-Induced Diabetes: A Review. Cureus.
 
Shchaslyvyi, A.Y., Antonenko, S.V. & Telegeev, G.D. (2024, August 16). Comprehensive Review of Chronic Stress Pathways and the Efficacy of Behavioral Stress Reduction Programs in Managing Diseases. International Journal of Environmental Research and Public Health.
 
Song, H., Fang, F., Arnberg, F.K., Mataix-Cols, D., de la Cruz, L.F., Almqvist, C., et al. (2019, April 10). Stress Related Disorders and Risk of Cardiovascular Disease: Population Based, Sibling Controlled Cohort Study. The BMJ.
 
(2022, October 21). Stress and Cancer. National Cancer Institute. https://www.cancer.gov/about-cancer/coping/feelings/stress-fact-sheet