Stress causes constricted blood vessels, higher blood pressure, and thicker blood, all of which increase the potential for plaque buildup and clogged blood vessels
Chronic stress can cause problems with cardiovascular health. In stress, blood vessels constrict and blood pressure increases, resulting over time in chronic high blood pressure. In addition the blood gears up for clotting, which has a very clear survival function in case of a critical bleeding wound where blood flow needs to be stopped right away. However, the blood is also thicker and stickier, which increases potential for clogging in the blood vessels. Meanwhile, the increased blood pressure can cause damage to blood vessel walls. This is particularly true in the arteries, as they branch into smaller and smaller tunnels; the point where they split can be particularly vulnerable to damage as pressure increases. The areas that are damaged then become vulnerable to things in the blood sticking to them and creating clots. For example, the stickier ready-for-clotting blood might do this, as well as the excess circulating fat and cholesterol, which the body has released for quick access to lots of energy. This brings us to a second notable issue: atherosclerosis, which refers to the buildup of plaque in the arteries. All this creates increased potential for clogged blood vessels – the plaque can continue to stick to the blood vessel walls, or it can be come mobile and get jammed in a blood vessel somewhere else. This leads to blocked blood flow, which in some cases might manifest as a stroke (lack of blood flow to the brain) or heart attack. Some of this information comes form Robert Sapolsky’s book Why Zebras Don’t Get Ulcers, and this is an excellent resource for greater detail on stress-related cardiovascular problems and their causes.
As is mentioned in the how to reduce stress section, it is possible to de-couple the fight or flight response from anxiety-provoking situations in which there is in fact no physical danger present. These cardiovascular changes are preparing the body for action, so this is really not necessary for times that we are sitting at a desk worrying about bills, feeling overworked, or anything else that does not include immediate physical danger.
By decreasing the time we spend unnecessarily in the fight or flight nervous system, and increasing our time in the parasympathetic nervous system, we are taking a huge step toward preventing a number of cardiovascular problems.