Loneliness in our Human Code

Among social determinants of health, loneliness can hugely impact a person’s mental state, physical health, and overall wellbeing. In this brief, we explore how social determinants of health, with a focus on loneliness, affect health over the course of a lifespan, taking into consideration the unique circumstances and needs at each stage of life.

Social isolation costs us...

8 years

of life lost, or the equivalent of smoking 15 cigarettes a day1


dollars in additional federal spending, every year2

When we feel excluded, we lose our fight against disease.

It increases our risk for3,4

heart disease
type-2 diabetes
blood pressure
high blood pressure
metastatic cancer

It increases impacts for our body's functions4,5,6,7

blood vessel
narrowing blood vessels to preserve body heat
elevating levels of the stress hormone cortisol
reducing antibody protection
decreased cognition
decreasing cognitive function

It's not just a feeling.


Is a co-morbidity

We feel lonely when our current number of social relations (and the quality of those) do not match what we desire. This feeling can lead to a loss of our sense of belongingness, satisfaction with life, and is associated with the onset of co-occuring physical and mental illnesses.8,18

Manifests as physical pain

A broken heart exhibits similar physical pain levels as a broken limb because our nervous system processes social rejection in the same area of the brain as physical pain. Evolution has wired socialization into the brain’s automatic reflexes on account of human contact dramatically increasing our chances of survival.14,15

Is a dysfunction of the brain

The default for the human brain is to assess and respond to our social context and stimuli, otherwise known as our “default network". When we feel socially fulfilled, there is a boost in our brain’s reward center (activating dopamine and oxytocin) along with healthy function in the parts of our brain that process social exclusion.11,12,13

Can affect gene expression

Studies have found that there may be genomic and hereditary indicators for loneliness, including a study of older people that found 209 abnormally expressed genes in their lonely group. In the lonely people, genes in charge of activating inflammation were over-expressed while those regulating antiviral and antibody mechanisms w
ere under-expressed.6,9,10

The causes and consequences are unique to every person.

Take a look at how social connection varies across our lifespan

Resilience in Our Human Code

While these are statistically relevant, humans have the ability to survive and surpass their circumstances to live full and healthy lives. Loneliness, and other social, circumstantial, and behavioral determinants have as much impact on your health as your biology or genetics. If you or someone you know is feeling lonely, check out resources in your neighborhood or reach out to talk to someone. Sometimes a little bit of human contact can go a long way towards living a healthier life.

Take Steps Now34

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Vanessa Li, University of Washington

Vanessa specializes in health systems and public health modeling, with an emphasis in socio-structural factors of disease. At the time of this paper (2018), she received a Bachelor of Science in Public Policy with double minors in Business Economics and Global Health from the University of Southern California, and later a Master of Public Health from the University of Washington. As of 2020, Vanessa works as an epidemiologist at the MITRE Corporation.

Jen Patel, GoInvo

Jennifer is a designer-developer hybrid specializing in user interface design and front-end development. She creates beautiful designs using big and small data, often for health and enterprise services. Jennifer joined Invo in 2011 and is a graduate of the Rochester Institute of Technology.


Juhan Sonin, GoInvo, MIT

Juhan Sonin leads GoInvo with expertise in healthcare design and system engineering. He’s spent time at Apple, the National Center for Supercomputing Applications (NCSA), and MITRE. His work has been recognized by the New York Times, BBC, and National Public Radio (NPR) and published in The Journal of Participatory Medicine and The Lancet. He currently lectures on design and engineering at MIT.

Parsuree Vatanasirisuk, GoInvo

Parsuree is a user experience designer and illustrator with background in industrial design. She makes the complex beautiful and approachable through illustration and information design. Parsuree joined Invo in 2018, and has a BA in Industrial Design from Chulalongkorn University and a MFA from Rochester Institute of Technology (RIT).


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