The Secondary Effects of Loneliness and Isolation

Loneliness and isolation have various secondary effects on long-term health. On their own, they are already challenging states to manage. This is most likely because, historically, humans have always been social beings, relying on communication and connections with others to further civilization. Loneliness and social isolation are not necessarily the same. As defined by the CDC, social isolation implies a “lack of social connections” or infrequent social contact, while loneliness refers to a feeling of solitude regardless of the number of social connections a person has. When loneliness and isolation persist for longer periods of time, they can be detrimental to both the mental and physical wellbeing of people of all ages. 

The Physical Effects of Loneliness and Isolation

Social isolation has been compared to smoking 15 cigarettes a day by the National Institute on Aging. That is, prolonged loneliness and isolation can have the same negative effects on health as smoking at least half a pack of cigarettes every day. The feelings of loneliness and isolation People who experience social isolation and loneliness are, on average, more likely to be admitted to both nursing homes and emergency rooms. Given the lifestyle associated with isolation and loneliness, people who experience these states may experience a 32% higher risk for stroke and a 29% higher risk for heart attack and/or death from heart disease, a 2022 report by American Heart Association states.

The negative effects of social isolation and loneliness impact adults aged 50 and older even more than they do younger people. Generally, persistent isolation and loneliness can increase the risk of premature death from all causes, according to the CDC. This is not only similar in risk to smoking, but also to obesity and physical inactivity. And, among heart failure patients aged 50 and older, loneliness was associated with a 68% higher risk of hospitalization and a nearly four times higher risk of death. A combination of feeling lonely and being socially isolated has also been associated with chronic inflammation.

Other studies have connected loneliness and social isolation to other physical health effects in middle-aged and older adults. Prevailing feelings of loneliness, experienced for years at a time, are strong predictors of an increase in blood pressure. Feeling lonely during the day has also been correlated with poorer sleep quality, including increased levels of cortisol upon waking up. This means the effects of loneliness and isolation impact not only physical performance but also the body’s restorative abilities. 

The Mental and Emotional Effects of Loneliness and Isolation

As mentioned earlier, the secondary effects of loneliness and isolation expand beyond physical health into mental and emotional health. One of the biggest impacts of prolonged social isolation is a decline in cognitive function. In fact, studies have shown that social isolation can result in a 40% increase in the risk of dementia, most notably in middle-aged adults and older. The impact of social isolation and loneliness on cognitive function are also observable in recall and verbal fluency.

Loneliness has also been linked to higher rates of depression, with higher levels of loneliness seeming to cause more symptoms of depression. This can also be said about anxiety and low self-esteem, which are often present alongside symptoms of depression. Not to mention, isolation can permeate existing depressive and anxious feelings, thereby worsening the decline in mental wellbeing.

Finally, social isolation has the potential to produce schizophrenia-related symptoms, in some cases acting as an early warning sign of the condition. While schizophrenia is often the result of genetic factors and early life events, social isolation can not only act as a catalyst for its symptoms, but also exacerbate them.

As social isolation and loneliness can have so many negative effects on both physical and mental health and wellbeing, it is important to take social connections seriously and encourage everyone, especially middle-aged and older adults, to foster and maintain meaningful relationships. 


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