Why stress is making you sick

New research explains why pressure attacks our cells and makes us more vulnerable to disease

Stress can cause physical illness by hijacking the immune system, according to a new study.

Researchers at the University of Michigan have identified how stress interacts with cells that are supposed to protect the body against infection diseases and manifests into physical illness.

The study revealed stress can impact the response of 'defence chemicals', or substances that fight off bacteria or viruses, amplifying inflammatory and allergic reactions such as irritable bowel syndrome, asthma and autoimmune disorders such as lupus.

Doctors could start prescribing stress management tools like breathing exercises and yoga to treat disorders like asthma and symptoms of irritable bowel syndrome.

The study, published in the Journal of Leukocyte Biology, revealed stress receptors, known as corticotropin-releasing factor (CRF1), send signals to certain immune cells, called mast cells, and control how they defend the body.

Mast cells, a type of white blood cell, are involved with inflammatory responses such as hypersensitivity and allergic reactions when the immune system fights off a perceived threat. These cells are also triggered during stressful situations.

Researchers conducted a mouse study to examine the immune cell responses to psychological and allergic stress. One group of mice had stress receptors on their mast cells, while the other group had no stress receptors.

They discovered that the mice with stress receptors had high levels of disease, while the mice without stress receptors had less disease and were protected against both psychological and allergic stress.

Adam Moeser, an associate professor who specialises in stress-induced diseases, said when mast cells are triggered during stressful situations they are vulnerable to being controlled by stress receptors.

'When this happens, CRF1 tells these cells to release chemical substances that can lead to inflammatory and allergic diseases such as irritable bowel syn-

drome, asthma, life- threatening food allergies and autoimmune disorders such as lupus,' explained Moeser.

This means chemical substances like histamine, which is produced by mast cells and known to help the body get rid of invading allergens like pollen, can become life-threatening.

In a normal response to an allergen, histamine would cause an allergic reactions such as inflammation, itching, sneezing and runny nose.

Researchers said this response can be intensified when someone has a severe allergy or is under a lot of stress, causing severe symptoms such as trouble breathing, anaphylactic shock and even death.

'This work is a critical step forward in decoding how stress makes us sick and provides a new target pathway in the mast cell for therapies to improve the quality of life of people suffering from common stress-related diseases.'

A 2017 study published in the journal Psychiatric Services has found that 8.3 million adults in the US suffer from stress, anxiety and depression.

'In the past, you may go out and meet with your friends and talk about something, but when you got home you'd go to sleep,' Dr Harsh Trivedi, president and CEO of Sheppard Pratt Health System, a Maryland mental health provider, told CBS News. 'The difficulty now is you can't really turn things off. We don't necessarily have downtimes to recharge and get our bearings straight again.'

Sleep and stress are intertwined, according to the American Psychological Association. They say when stress increases, length and quality of sleep decreases.

And when people aren't getting the minimum recommendation of seven to nine hours of sleep at night, they feel even more stressed.

Stress, a physical response to feeling threatened or anxious, has been the root of many health concerns including, insomnia, depression and high blood pressure.

One 2016 study published in the journal Personnel Psychology followed more than 2,000 people for 36 years and found people with stressful were more likely to have health issues and die early.

Another study published in a 2013 issue of PLOS One revealed stress is linked to an increased risk of heart attack, heart disease and an increased risk of death.

In addition to sleep problems, common signs and symptoms of stress include depression, difficulty making decisions and trouble concentrating.