Loneliness may lead to depression, especially where loneliness becomes prolonged. In particular, loneliness predicts subsequent increases in depression. Therefore responding to signals of loneliness are important. However, depression does not predict escalation of loneliness. Furthermore, loneliness has been found to be a mediator from anxiety to depression.
Feelings of loneliness might increase the risk of the onset of dementia, and other mental illnesses. The increased risk of dementia is less related to being socially isolated, and more related to missing quality relationships. Without perceived meaningful connections our immune system is lowered.
Loneliness can go away. While most people experience some form of loneliness you can conquer loneliness by increasing the number of meaningful quality relationships. You need people you can trust and depend on in a variety of settings. If you are unable to develop those meaningful relationships get professional help.
Loneliness does affect our health, especially when the loneliness becomes prolonged. Physically, loneliness can cause high blood pressure, coronary heart disease, stroke, metabolic syndrome, high stress-sensitive hormone cortisol, and altered gene expression. Mentally, loneliness can cause social anxiety, depression, paranoia, dementia, and obsessive compulsive symptoms.