It's one of those unexpected emergencies: you are walking down the street, on your way to meet a friend for dinner. You are already thinking about what you would like to eat, savoring your hunger. Come around the corner and -- oh no, YOUR EX!
As we know activities throughout your body shift immediately to meet crisis: your digestive tract shuts down and your breathing rate increases. Secretion of sex hormones in inhibited, adrenaline, noradrenaline, and glucocorticoids pour into the bloodstream. Your goal is to move as fast as you can so that your ex doesn't spot you so if you need to move as fast you can, one of the most important additional things that better be going on is an increase in your cardiovascular output, in order to deliver the oxygen and energy needed to move those muscles faster.
Never is the maladaptiveness of the stress response during psychological stress clearer than in the case of the cardiovascular system.
You sprint through the streets terrified, and you alter the cardiovascular functions to divert more blood flow to your thigh muscles. In such cases, there is a wonderful match between blood flow and metabolic demand. In contrast, if you sit and think of major deadline looming next week, driving yourself into hyperventilating panic, you still alter cardiovascular function to divert more blood flow to your limb muscles. Crazy. And, potentially, eventually damaging.
How does stress induced elevation of blood pressure during chronic psychological stress wind up causing cardiovascular disease, the number one killer in the UK and developed world? Basically your heart is just a dumb, simple mechanical pump, and your blood vessels are nothing more exciting than hoses. The cardiovascular stress-response essentially consists of making them work harder for a while, and if you do that on a regular basis, they will wear out, just like any pump or hose you would buy at B&Q (other stores are available).
THE FIRST STEP IN THE ROAD TO STRESS RELATED DISEASE IS DEVELOPING HYPERTENSION.
(Hypertension: Resting blood pressure where systolic pressure, the upper number, reflecting the force with which blood is leaving your heart, is above 140. or when diastolic pressure, the lower number, reflecting the force with which blood returns to your heart, is above 90, is considered elevated. NHS recommends Blood Pressure optimal levels to be 120/80).
Couple social stress with a high calorie diet and the effects synergize, and plaque formation goes through the roof. Form enough atherosclerotic plaques to seriously obstruct flow to the lower half of the body and get claudication, which means that your legs and chest hurt like hell for lack of oxygen and glucose whenever you walk; you are then a candidate for bypass surgery.
Increase stress and increase blood pressure, and, as the blood moves with enough force, increase the chances of tearing that plaque loose, rupturing it. So maybe you have had a plaque being way too small to cause trouble. But tear it loose now, form what is called a thrombus, and that mobile hairball can now lodge in a much smaller blood vessel, clogging it completely.
Clog up a coronary artery and you have got a myocardial infarct, a heart attack. Clog up a blood vessel in the brain and you have a brain infarct, a stroke.
If the above does not scary you I don't know what will! I for one learning this stuff really made me realise how fragile we are and if we put our body under chronic stress be it phycological, physical or through poor diet it will only respond one way, by making US SUFFER.
A lot of this information was taken from the book Why Zebras Don't Have Ulcers by Robert M Sapolsky