Modern scientific research reveals that mental health and physical health are mutually influenced, restricted and dialectically unified. Physical health is one of the basic conditions of mental health. Only with a sound body can we talk about a sound spirit. "A healthy mind resides in a healthy body" is the truth. The most obvious influence of physical condition on psychology and behavior is the acute and chronic diseases of the brain, which can cause some psychological diseases. Some studies in recent decades have confirmed that the main causes of some psychological diseases really belong to brain diseases. For example, the main cause of alcoholic psychosis is brain diseases caused by alcoholism; The main cause of senile psychosis is brain diseases caused by arteriosclerosis. Clinically, it is also found that when a person's brain is damaged by trauma or disease, his psychological activities will be completely or partially unbalanced.
In addition to the nervous system, the endocrine system will secrete a very small amount of hormones, but it also has a great impact on psychological function. For example, the main function of thyroid is to control the metabolism of individuals. When the thyroid gland secretes too much, the metabolism will be accelerated, accompanied by nervous reactions such as limb trembling, emotional excitement, anxiety, insomnia, inattention, and even thinking and cognitive activities will be affected. On the contrary, when thyroid gland secretion is insufficient, metabolism will be reduced, and the whole mental activity will tend to be dull, slow to respond, memory loss, mental retardation and frequent depression.
2. The influence of mental health on physical health
The above example is about the influence of physical condition on mental condition, but of course we can also learn many facts to illustrate the influence of mental condition on physical condition. The influence of emotion on physical condition is the most studied and easily seen in daily life at all times and in all countries.
When people are angry, afraid or anxious, their appetite often decreases, but the peristalsis of the stomach, congestion of the stomach wall, secretion of gastric juice and acidity increase. If this reaction continues, the stomach wall will be partially eroded by gastric acid, forming an ulcer. For another example, when people are angry, the increase of blood pressure is a normal physiological process. If anger can erupt, the nervous mood will be relaxed and the elevated blood pressure will drop to normal level. If such anger is suppressed for a long time, it can't break out, and the nervous mood can't be calmed down for a long time, then it may cause obstacles to the blood pressure regulation mechanism and form functional hypertension.
Long-term negative emotions can lead to organ dysfunction or tissue damage, which is called "psychosomatic disease" in modern medicine. These diseases mainly include coronary heart disease, arrhythmia, anorexia nervosa, bronchial asthma, migraine, neurodermatitis, other allergic skin diseases, diabetes, hyperthyroidism, menstrual disorders and so on.