Nearly 2,000 years ago, the Roman poet Juvenal began to link physical health and mental health in his famous saying mens sana in corpore sano. 

It was not until the mid-20th century that the World Health Organization (WHO) came to define health as the state of complete physical, mental, and social well-being of a person and not merely as the absence of disease. This implies and recognizes that medical treatments should focus on the whole person and not only on the physical aspects of a disease.

However, up until a few years ago, doctors limited themselves to treating physical diseases. Nowadays, thanks to innovations and recent research, we know that patients’ mental health greatly influences their physical well-being.

What is the impact of mental health on physical health? Let’s look at a few examples:

Stress and the immune system

Recent studies in the field of psychoneuroimmunology have found some of the mechanisms by which the nervous system and the immune system interact. 

While some stress can be positive in specific cases—such as when it is a biological response to external threats—, suffering from chronic stress weakens our immune system. Chronically stressed people show consistently high levels of cortisol, which impacts our immune system by reducing its ability to function properly.

Anxiety and heart diseases

It is well known that psychological factors such as stress and depression play an important role in both the onset and progression of heart diseases. Moreover, we are currently aware that anxiety is a potential risk factor for heart disease, on par with another significant factor: high blood pressure. A 2010 meta-analysis indicates that patients with anxiety are 26% more likely to suffer from heart disease and 48% are more likely to die from it. 

According to the same study, a person’s anxiety levels can serve as a marker to prevent the possible onset of heart disease in the future.

The brain and the digestive system

The brain and the digestive system are intimately connected and influence each other. While digestion can have an impact on our mood and emotions, stress and anxiety can aggravate inflammatory diseases such as gastritis or colitis. 

Therefore, watching our diet will improve our emotional well-being, just as taking care of our mental health will have a positive effect on our digestive processes.

Mental health and cancer

Although much progress has been made in recent years on the treatment of oncological diseases, cancer is still one of the most dreaded diseases due to its very nature and its high mortality rates. 

It is not surprising, then, that cancer has a close relationship with the mental health of patients. 

On the one hand, people diagnosed with cancer may suffer from stress, depression, or anger management issues. On the other hand, psychological factors influence the patient’s well-being during treatment and the progression of the disease. In fact, it is not uncommon for patients to suffer from the side effects of chemotherapy (nausea and vomiting) even before they have received it.


Mental and physical health are closely linked. This link has become particularly relevant in the last two years and especially during the COVID-19 lockdowns. During this time, many people have experienced increased levels of anxiety and stress, which have also had a negative effect on their physical well-being. 

Taking care of our mental health is critical to maintaining our overall well-being. Although it may often seem difficult, we should try to manage our stress levels and avoid stressful situations whenever possible. 

If we pay more attention to our mental health, we could achieve greater physical and emotional well-being.