Whenever the immune system is attacked by infections (viruses or bacteria), toxins, or even physical injury (such as a knee injury), it creates an inflammatory response — sending out messengers known as cytokines, which are either pro-inflammatory or anti-inflammatory. Damaged cells release chemicals including histamine, bradykinin, and prostaglandins, which cause blood vessels to leak fluid into tissues and create tissue swelling. While acute or short-term inflammation is a protective feature of the immune system, chronic inflammation can cause simultaneous destruction and healing of the tissues, ultimately wreaking havoc on your body long-term.
It’s not only physical injury or infections that can trigger an immune response; stress and emotional trauma cause inflammation as well. Long-term or chronic stress has actually been shown to change the gene activity of immune cells before they enter the bloodstream, priming them to fight infection when there is no infection. As a result, inflammation occurs unnecessarily but still wreaks havoc on tissues and body processes. Chronic inflammation is often associated with cancer and other disorders such as heart disease and high cholesterol. Brain inflammation, meanwhile, has been linked to several disorders, including Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis.