A first-of-its-kind original, scientific study showed that Personality Type is strongly correlated with certain health-risk factors and may predict susceptibility to specific chronic illnesses. These findings may help patients with innate predispositions to avoid developing serious medical conditions. 

About five years ago, I decided to apply my expertise and experience with personality type to help reduce untold suffering due to chronic disease. The stars lined up when I was invited to join a team of leading health researchers to collaborate on a large (n = 16,700) national study to better understand medication adherence. The study revealed such a strong correlation between personality type and medication adherence, that personality type analysis became a central feature in three subsequent studies. One of these studies was to determine if there is a relationship between personality type and modifiable health-risk factors.

Participating in this study was very attractive to me because, unlike inherited genetic conditions, modifiable risk factors can be mitigated when patients change certain behaviors.  And when they do, they may be able to avoid developing serious chronic diseases such as diabetes, heart disease and hypertension. Like our other research, this study involved a large (n = 10,500) representative national sample.

The Cost of Chronic Diseases – $3.6 Trillion Annually

Before I share which health risk factors people of different personality types may be susceptible to, I think it’s important to explain the relationship between personality type, risk factors and chronic diseases.

Chronic disease is an epidemic which affects approximately 133 million Americans – about 40% of the total population. In addition to incalculable and often needless human suffering, the economic cost is staggering. Chronic diseases – most of which are preventable through simple lifestyle changes – account for 86% of the 3.6 trillion dollars spent annually on healthcare in the US (CMS).

The CDC estimates that eliminating just three risk factors—poor diet, inactivity, and smoking—would reduce 80% of heart disease and stroke, 80% of type 2 diabetes, and 40% of cancer. 

It is estimated that 84 million Americans are pre-diabetic. Roughly half will develop type 2 diabetes, costing the US economy approximately $327 billion dollars, annually…and this is only one chronic disease!  Other largely preventable diseases also have staggering price tags: cardiovascular, $317B; smoking-related, $300B; obesity, $264B; alcohol-related, $250B and stroke, $33B.

How Personality Type Can Impact Chronic Disease

Once I started researching chronic disease, I was troubled and frankly shocked that so much misery could be prevented. As I dove deeper, I was surprised to learn that despite the enormous cost to patients and numerous healthcare stakeholders, no one had yet “cracked the code” and figured how to get people to change unhealthy behaviors. This revelation became the motivation for my research.

In our Modifiable Heath Risks study, all 10,500 subjects completed a validated personality type assessment. We also collected relevant demographic information which included age, gender, race / ethnicity, education level and geographic location. During our analysis, we sliced and diced the data many ways, including looking at whole four-letter types. But the single most powerful variable turned out to be Temperament (as described by David Keirsey). In this blog, I’ll share some of what we learned, and my thoughts as to the reasons for these findings.

The following table lists some of the risk factors we examined in our study: medication non-adherence, anxiety, depression, alcohol abuse, smoking, lack of exercise, poor nutrition, and sleep issues. The color coding identifies the number and type of risk factor associated with each temperament. Green = fewest, red = the most, and orange, those in between. (Please note: In my books and in this table, I call SJs “Traditionalists”, SPs “Experiencers”, NTs “Conceptualizers and NFs, “Idealists”). 

An algorithm developed to calculate the number of risk factors for each temperament and type revealed some dramatic findings: tests for statistical significance showed that Traditionalists (SJs) had virtually no risk factors, while Experiencers (SPs) had every single one!  Idealists (NFs) had four risk factors, and Conceptualizers (NTs) only two.

What are YOUR Health Risk Factors?

Traditionalists (SJs)

I wasn’t surprised to learn that Traditionalists had virtually no risk factors, which I believe, is due to a confluence of factors. By their nature, Traditionalists tend to be responsible, reliable, systematic, conservative, organized, practical, self-disciplined, like to follow rules and respect authority. As a result, they are more likely to schedule (and show up for!) regular medical checkups, get yearly flu shots, faithfully take prescribed medications, follow treatment plans, stick with exercise regimens, and live by the axiom “everything in moderation”, which means they consume less alcohol and watch what they eat.

Although a few of the Traditionalist types (ESTJ, ISTJ, ESFJ and ISFJ), did have some risk factors, none rose to the level of statistical significance.

Here is a finding that should make healthcare providers, health plans and health systems sit up and take notice: while Traditionalists comprise about 46% of the population, they only account for only about 5% of health risk factors. This means that roughly half of the population is responsible for only a very small percentage of healthcare costs. Fun fact: a disproportionate percentage of healthcare providers – especially those providing hands-on care – are Traditionalists. This makes sense because healthcare is all about being of service and demands strict attention to protocols, something Traditionalists’ value and are comfortable doing.

Experiencers (SPs)

Experiencers are a very different story. By their nature, Experiencers tend to be fun-loving, playful, casual, adaptable, practical people who like to live in the moment. Not especially impressed by authority, they cherish their freedom and chafe at rules that constrain their actions. 

Although they comprise about 27% of the population, they account for almost 50% of health risk factors. Because Experiencers typically “don’t sweat the small stuff”, they are less likely to schedule (and show up for) routine checkups and less likely to take medications as prescribed. Many – but not all – Experiencers enjoy the adrenaline rush that often accompanies taking risks, which also results in more injuries. But because they prefer to live in the moment, Experiencers don’t spend a lot of time worrying about the future consequences of their present behavior. This, combined with a tendency to procrastinate, means they typically don’t spend a lot of time thinking about their health.  

A close relative of procrastination is lack of self-discipline – another risk factor identified in our study. Once again, Experiences scored highest in this category.

While many Experiencers are also drawn to work in healthcare, they are most often found, and get the most satisfaction from being where the action is – as surgeons, EMTs or trauma nurses. 

Conceptualizers (NTs)

Conceptualizers tend to be logical, confident, competent, assertive, intellectual, strategic, and competitive. Because they place such a high value on competency, they are lifelong learners who are usually well read and enjoy acquiring knowledge. Their combination of Intuitive perception and Thinking judgement (NT) gives them an affinity for understanding complex subjects such as science, which is the basis for modern medicine. Many Conceptualizers love to conduct research and show up to doctors’ appointments armed with the latest scientific research about their condition (some of which the physician may not even be familiar with). 

According to our research, the two risk factors that most affect Conceptualizers are alcohol abuse and poor nutrition. While this research didn’t attempt to explain the underlying reasons for risk factors, a possible explanation consistent with personality type theory is that Thinkers tend to be more independent and may be less sensitive to the effect of their (potentially negative alcohol-induced) behavior on others.

The other risk factor reported by Conceptualizers was “poor nutrition”. One question in the study asked about fast-food consumption, which turned out also to be correlated with Extraversion and Perception. The two types with the highest scores were ENTP and ENFP. A plausible explanation for this finding is that both types like to be spontaneous and tend to avoid tedious, arduous tasks (such as tracking food intake and dieting). 

Idealists (NFs)

Idealists are typically empathetic, perceptive, sensitive, idealistic, compassionate, empathetic, communicative people. The first thing you notice when looking at the table is that their four risk factors – anxiety, depression, alcohol abuse and sleep issues – are all are related to mental health. It is not surprising that Idealists’ unique combination of characteristics make them most vulnerable in this area, since Idealists are “hard-wired” to be worriers. Their Intuitive perception (N) allows them to imagine possibilities. Their Feeling judgment (F) encourages (some would say “forces”) them to make decisions based on their deeply held values. As a result, Idealists see the way the world could and should be – but frequently, is not. The ultimate “empaths,” when Idealists say, “I feel your pain,” they mean it.

The finding of the Modifiable Health Risk study relating to anxiety and depression were so dramatic, I prevailed in getting the research team to perform a separate analysis focused only on these two risk factors. In addition to all participants being typed, they also completed the PHQ-4, a validated instrument that measures anxiety and depression. Taking this “deeper dive,” we were able to determine how prone each of the sixteen types are to anxiety and depression, based on their percentage in the US population. 

The results were dramatic and powerful. 

Traditionalists were the least prone to report depression, while all four Idealist types were significantly more prone. At the individual type level, the results were even more pronounced. At the extreme ends of the continuum, ISTJs were 25% less likely, and INFPs were 41% more likely to report depression. 

The results for anxiety were similar: ISTJs were 31% less likely, and INFPs 49% more likely to report anxiety. And with severe anxiety/depression, ISTJs were 36% less likely, and INFPs 86% more likely to report severe anxiety/depression.


Research with Practical, Far Ranging Implications 

Ever since I first learned about type, I’ve been amazed by how much of human behavior it helps to explain. I must admit that I love conducting research which involves personality type – but only if the results can benefit people in real and practical ways. While I’m not surprised that this study showed such a strong correlation between type and health risk factors, I am nevertheless gratified by how many different populations can benefit from these insights:

Adults who have a propensity for experiencing anxiety or depression can become aware of and avoid certain physical, environmental, or emotional triggers. Types at greatest risk tend to be hyper-sensitive and to put others’ needs ahead of their own. Such individuals may benefit from therapy and learning how to set healthy boundaries.

Parents of children prone to anxiety or depression can better understand and become sensitized to their needs, and help their children feel safe sharing their feelings.  

Healthcare providers – especially pediatricians – can help parents become aware of their children’s potential predispositions earlier and gain a heightened awareness of instances when referrals to a mental health professional may be more appropriate. 

And health plans can better allocate precious resources by quickly identifying patients at greatest risk and providing them with tailored approaches to staying healthier through tools like our research-inspired Individualized Wellness Plans (IWPs).  

Paul Tieger
Paul D. Tieger is the Founder and CEO of SpeedReading People, LLC. He is an internationally recognized expert on – and author of five breakthrough books about – personality type including The Art of SpeedReading People and the one-million copy best-seller Do What You Are. A jury consultant for twenty-five years, Paul pioneered the use of Personality Type to help trial attorneys understand and communicate with jurors and has worked on dozens of high profile civil and criminal cases including the first physician-assisted suicide trial of Dr. Jack Kevorkian. Paul holds a BS degree in Psychology and an MS in Organizational Behavior.