A young adult's personality may hold clues to his or her health later in life, so perhaps doctors should assess their patients' personalities during checkups, a new study says.

In the study, people who were more conscientious — a personality trait that indicates a tendency to be self-disciplined and orderly — at age 26 were in better health 12 years later than people who were less disciplined.

Among those who were the least conscientious as young adults, 45 percent went on to develop health problems by age 38, such as high cholesterol, high blood pressure and gum disease, while just 18 percent of the most conscientious people developed one of these health problems, said study researcher Salomon Israel, of Duke University. [10 Fitness Apps: Which Is Best for Your Personality?]

Another personality trait, called "openness to experience," was also linked with better health later in life. People who score high in this personality trait tend to be curious, imaginative and prefer variety to routine.

The findings held even after the researchers took into account factors that could affect a person's health, such as socioeconomic status, weight and smoking habits, according to the study.

Personality check

The study involved more than 1,000 people living in New Zealand. Participants' personalities were assessed twice: once by a person who knew the participant very well — such as a best friend, family member or romantic partner — and once by a nurse and receptionist who'd only just met the participant. These two assessments tended to match up, and the results of the study were similar regardless of which assessment was used.

The findings suggest that brief personality measures may help doctors anticipate which young adults are at greater risk of developing poor health, the researchers said.

"Integrating personality measurement into primary care may be an inexpensive and accessible way to identify which young adults are in need of their doctors’ attention to promote a healthy lifestyle while they are yet young, in time to prevent disease onset," the researchers wrote in the March issue of the Journal of Personality and Social Psychology

Previous studies have linked personally traits with health outcomes later in life, but many of these studies relied on participants' self-reports. The new study adds to the research by showing that a person's personality, as measured by someone else, also predicts future health, the researchers said.

Personality and health

Being conscientious may lead to better health because people with high levels of this personality trait tend to have a lot of self-control, and are less likely to smoke, abuse drugs or alcohol, or engage in risky healthy behaviors, the researchers said. Conscientious people are also more likely to have an active lifestyle and healthy diet than those with lower levels of the trait.

People who are more open to experiences also tend to have higher IQs, which may explain the link between this trait and health, the researchers said. People with high IQs may be more likely to have knowledge about how to prevent disease as they get older, to seek medical attention if they get sick and to adhere to complex treatments, the researcher said.

Interestingly, the personality trait of neuroticism, or a tendency to feel anxious and moody, was not linked with future health, even though people have theorized that stress and anxiety may translate to ill health.

More research is needed to study exactly how personality assessments could be integrated into health care, whether reports by the patient or the observer are better, and whether knowing a patient's personality really does improve the patient's health.

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