Probably everyone has had a moment in their life when their vision suddenly seems to go dark.
Moreover, the darkness in the eyes can be different: sometimes it is simply a sharply thickening darkness, which is accompanied by dizziness and even loss of consciousness, and in simpler cases the world “turns grey” a little.
In fiction, this state is described very poetically, but in reality, there is nothing romantic about this gray fog that envelops reality.
It is not necessary to have serious diseases, almost everyone experiences darkening in their eyes from time to time, and in most cases this is observed if you stand up abruptly. Why does this happen?
In most cases, this is a warning of possible fainting: the brain suddenly experiences a serious lack of oxygen, and hastily turns off all functions that are not directly related to the life support of the body.
This energy-saving mode may be justified from a biological point of view, but it can really be scary.
Since oxygen is delivered to the brain along with the blood, then in a technical sense the pre-fainting state is explainable: the blood flow to the brain has decreased, there is less oxygen, and that is why it gets dark in the eyes.
When you suddenly stand up and change your body position, the blood flow to the brain can actually decrease for some critical moments, but this can also be caused by illnesses of varying degrees of severity.
Why don't the required volumes of blood reach the brain, and if they do, are they not sufficiently saturated with oxygen?
For example, it could be hypotension - low blood pressure, and this condition in turn could be a symptom of a more serious disease.
Another reason for oxygen starvation of the brain is that there is no one to transport oxygen. That is, there are not enough red blood cells, hemoglobin, in the blood. This condition is called anemia.
Narrowing of blood vessels can also provoke pre-fainting conditions, and it is imperative to check what exactly is causing this narrowing.
It may be a side effect of taking certain medications or a symptom of atherosclerosis.
Literally anything can affect the condition of the body: an incorrectly chosen fasting diet, excess physical activity, hormonal imbalance, age-related changes.
This is why regular medical examinations are essential, because any problem is easier to treat when it has not yet become chronic.
We previously reported on why you should yawn and not hold back .