Skip to main content

Verified by Psychology Today


How Do Your Family and Friends Affect Your Health?

Use the science of relationships to improve your mental and physical health.

Key points

  • Positive social relationships are associated with better immune functioning, responses to stress, and cardiovascular health.
  • Loneliness is related to earlier death and greater physical health problems.
  • The quality of one's social relationships matters more than the quantity.

When I’m feeling down, almost everything inside me wants to sit on the couch and watch a favorite show to relax and zone out. However, the social scientist voice in me always reminds me in these moments that social support is one of the best methods to start feeling better. Sure enough, when I reach out to my spouse, my mother, or a friend to connect, I almost always feel better after. The social scientist voice then reminds me that the power of social support is real and that there are many studies showing that positive relationships are beneficial for both our mental and physical health.

The science of loneliness

Some of the strongest evidence for the power of social support comes from research on social isolation and loneliness. We know that people who are socially isolated are more likely to have health problems and to die sooner than people who are more socially connected (Hawkley & Cacioppo, 2010). As unrealistic as it sounds, being socially isolated is about as bad for your health as smoking, having high blood pressure, and not exercising (Uchino et al., 1996).

Interestingly, your social relationships can actually change your underlying biology. Loneliness and the quality of our relationships both change how your body reacts to stress and how your body works even when there is nothing immediately stressful to deal with. We are a social species, and being lonely makes us more aware of threats in the environment (since we don't have anyone to help us out if something bad happens). Our biology can actually motivate us to seek out social connection for our safety and our well-being (Cacioppo et al., 2011).

Being lonely is related to many biological changes. Loneliness is associated with higher blood pressure with age and also greater resistance in your blood vessels when blood is traveling through the body (which increases pressure on your cardiovascular system). People who are lonely have a harder time appropriately responding to stress (Cacioppo et al., 2015). Often, the body's stress system (that produces the stress hormone cortisol) has difficulty responding to and then recovering from stressful situations, either responding too much or too little, both of which are not good for our health and safety. Loneliness is also associated with poorer sleep, which is bad for both mental and physical health.

Social connection and health

Interestingly, our social relationships can affect our immune system as well. One study showed that adults with more types of social relationships (spouse, parent, friend, coworker, etc.) were less likely to develop a cold when exposed to the cold virus (Cohen et al., 1997). Even among all the people who developed a cold, the people with more types of social relationships had less severe symptoms and had a better time containing their colds, which prevents it from spreading to others as easily.

On the other hand, people who are more socially connected live longer and healthier lives. To figure out what helps us live long and healthy lives, researchers study communities in which large numbers of people are known for living healthily past age 100. These communities are called blue zones. One of the major findings from studying these blue zones is that their residents who are 100 years old or older usually report a strong sense of community with a large amount of social support. Strong social relationships in the community are a major source of health and happiness, and this is important to remember when we're trying to build healthy lives and communities.

A major caveat to this research is that not all relationships are created equal. Abusive, unsupportive, and negative relationships are bad for your health. Individuals who are abusive, manipulative, make you feel unsafe and unsupported, or disregard your feelings and needs cause additional stress rather than relieve stress.

Is it about quality or quantity?

At this point, you might be wondering: How much social interaction is enough to positively impact your health? Unfortunately, we don’t know for sure. It likely varies between people because the level of support that's right for you is more subjective than objective. For example, some people may have one close friend or family member whom they rely on and have frequent contact with, and they may feel very loved and supported overall. On the other hand, someone may engage in social interaction all day without ever feeling supported and loved.

The most important indicator of social support is likely how you feel about your relationships. Feeling loved and supported by your social network is beneficial to your physical and mental health. Feeling lonely and unsupported is not. As a result, it's more about the quality of your relationships than the quantity.

How can we use social support to improve our lives?

  1. When you’re feeling down, try reaching out to someone who makes you feel good. You can reach out via text, phone, or in person, though research suggests you may get an added boost from hearing their voice via phone or hugging them in person versus texting.
  2. Focus on frequently contacting individuals who are important to you. Perhaps plan a weekly or monthly catch-up with them to remain connected.
  3. Reach out to connect with individuals who you believe may be lonely or isolated. Reaching out will likely improve mental and physical health for both of you.
  4. If you have a role within a community, implement ways to build social connections between people within it to strengthen relationships and improve the health of the group.

Knowing about the powerful effect of social support on health can help you and others around you. Checking in about how you feel after connecting with loved ones can help reinforce our tendency to reach out to others when we’re in need. And if you’re making any sort of plan to improve your health, make sure you include a plan for reinforcing your social support network. It may be as helpful as those extra trips to the gym.


Cacioppo JT, Cacioppo S, Capitanio JP, Cole SW. The neuroendocrinology of social isolation. Annu Rev Psychol. 2015 Jan 3;66:733-67.

Cacioppo, J. T., Hawkley, L. C., Norman, G. J., & Berntson, G. G. (2011). Social isolation. Annals of the New York Academy of Sciences, 1231(1), 17-22.

Cohen S, Doyle WJ, Skoner DP, Rabin BS, Gwaltney JM Jr. Social ties and susceptibility to the common cold. JAMA. 1997 Jun 25;277(24):1940-4.

Hawkley, L. C., & Cacioppo, J. T. (2010). Loneliness matters: A theoretical and empirical review of consequences and mechanisms. Annals of behavioral medicine, 40(2), 218-227.

Uchino, B. N., Cacioppo, J. T., & Kiecolt-Glaser, J. K. (1996). The relationship between social support and physiological processes: a review with emphasis on underlying mechanisms and implications for health. Psychological bulletin, 119(3), 488.

More from Jenalee Doom Ph.D.
More from Psychology Today