A study has shown that sociable and outgoing people tend to be overweight while anxious and worried ones are usually thinner.
Masako Kakizaki of Tohoku University and colleagues questioned 30,000 people, aged between 40 and 64, in northeastern Japan about their height and weight. The participants were also given a personality test.
The researchers found that extroverts had a greater chance than other people to have a body mass index (BMI) of more than 25, a commonly used definition of overweight.
After controlling for other factors, such as smoking, men in the most outgoing group were 1.73 times more likely to be obese than their most introvert counterparts.
Meanwhile sociable women were 1.53 times as likely to be obese.
On the contrary, those who had the most anxious personalities were twice as likely as the least anxious to be underweight, or have a BMI of less than 18.5, the researchers said.
"These results may provide clues to devising more effective measures for preventing overweight, obesity or underweight," News.com.au quoted the researchers, as saying.
The study is published in the Journal of Psychosomatic Research.