Because the Brain is in charge of assessing whether a Threat exists and on that basis decides on how much Adrenaline and Cortisol hormones are produced to meet the danger and protect the person, and in ordinary non-threatening situations it is the job of the Brain to manage and synchronise the Body part functions, like regulating heartbeat, like sending sufficient blood to your abdomen after you have eaten in order to be able to digest your food, and so on, if the Brain decides that there is what it deems as a Chronic on-going threat, then it takes away most of the blood to send it to the arms and legs in order for the person to be able to engage with Fight or Flight.  This means that most bodily functions will be stopped to allow all the strength to go to the parts that can fend off the danger.

Moreover, the hormones that are produced that go round the body in the blood as it circulates, cause damage to the body organs and can cause the following illnesses

• High Blood Pressure
• Thyroid Dysfunctions
• Heart Problems and Various Dysfunctions
• Liver Dysfunction
• Kidney Dysfunction
• Arthritis and Joint Problems
• Shoulder and Back Pain
• Cancers
• Asthma and Lung Problems
• Renal Dysfunctions

And a lot more.