The term "neurotic" is often haphazardly thrown around with the likes of other psychological disorders like OCD and psychosis, but this presents a large issue: Being occasionally worried or biting your nails doesn't necessarily equate to mental disorder. According to Gregg Henriques, professor of psychology at James Madison University, "A person high in neuroticism is someone who is a worrier, easily upset, often down or irritable, and demonstrates high emotional reactivity to stress."
They'll also likely exhibit behaviors such as social repression and ritualized habits like hair-pulling, ordering and cleaning, and in more severe physiological cases, drinking or binging and purging. You can also be low in trait neuroticism, exhibiting less extreme versions of these behaviors and thought patterns. The diagnosis, however, should be left up to a mental health professional.
For a group of UK residents who identify as neurotic and completed an assessment to test their levels of neuroticism, a silver lining was found within their diagnosis: After being followed by researchers for six years, those who rated their health as fair or poor and were high in neuroticism had a "small protective effect against dying prematurely." Those who scored highest in neurotic tendencies related to worry and vulnerability also had a lower risk of death, regardless of their perceived state of health. Interestingly, however, those with high levels of neuroticism who rated their health as excellent had no relationship with their risk of death.
Lead researcher, Catharine Gale, a faculty member at the University of Edinburgh and University of Southampton, suggested that the reason death rates were lower among those who perceived their own health as poor was because these individuals probably preventatively met with physicians more often and could get earlier diagnoses and treatment plans than those who didn't.
However, their neurosis didn't prevent them from taking part in unhealthy behaviors: Many subjects still engaged in smoking, being sedentary, and eating unhealthy foods. So while researchers are confident in the correlation between neuroticism and death rates, Gale says being neurotic isn't grounds for a healthy life overall. She notes that positive thinking has a far better effect on your health.