How is loneliness harmful to your health?
Lonely people have differences in their biology that can make them more vulnerable to disease. Lack of social connection and subsequent loneliness affects the immune system and promotes inflammation. Inflammation is necessary to help our bodies heal from injury, but when it goes on to long, it may raise the risk of chronic diseases. People who feel lonely are at a higher risk of many diseases including heart disease, high blood pressure, and Alzheimer's disease. Some of the increased risk of disease may come from changes in behavior. People who feel isolated may not have friends or family encouraging them to eat right, exercise, or see a doctor.
What does it mean to have healthy social connections?
The quality of our relationships matter and if a relationship isn't going well, it can result in negative health-related consequences. Married couples tend to live longer and have better heart health than unmarried couples. Studies have found that when one spouse improves his or her health behaviors - such as by exercising, drinking or smoking less, or getting a flu shot - the other spouse is likely to do so too. However, when marriages are full of conflict, these health benefits may shrink.
Other relationships (friends, family, neighbors, co-workers, clubs, and religious groups) are important too. People who have larger and more diverse types of social ties tend to live longer and have better physical and mental health than those with fewer such relationships.
Social support may be especially protective during difficult times and the act of hugging appears to shield against stress.
Social ties can have mixed effects on our health but overall, research suggests that the benefits of interactions with other can outweigh any risks. Involvement with other people across diverse situations by belonging to different groups, volunteering in different ways, being involved in a church, or involved in your neighborhood can clearly have a very positive effect on health.
Strategies for Improving Social Health
Kiecolt-Glaser JK, Loving TJ, Stowell JR, et al., Arch Gen Psychiatry. 2005 Dec;62(12):1377-84. PMID: 16330726.
Cohen S, Janicki-Deverts D, Turner RB, Doyle WJ. Psychol Sci. 2015 Feb;26(2):135-47. doi: 10.1177/0956797614559284. PMID: 25526910.
Cohen S, Doyle WJ, Skoner DP, et al. JAMA. 1997 Jun 25;277(24):1940-4. PMID: 9200634.
National Institutes of Health