Why you should ask your friends how long you will live.

1. Introverts versus extroverts

Outgoing, sociable people have the strongest immune systems, a recent study finds.

Those who are the most careful, though, are more likely to have a weaker immune system response.

The research found no evidence, though, that a tendency towards negative emotions was associated with poor health.

2. Optimists versus pessimists

Optimists have healthier hearts than pessimists, a study of over 51,000 adults has found.

Professor Rosalba Hernandez, who led the study, said:

“Individuals with the highest levels of optimism have twice the odds of being in ideal cardiovascular health compared to their more pessimistic counterparts.
This association remains significant, even after adjusting for socio-demographic characteristics and poor mental health.”

Optimists also had healthier body mass indexes, were more physically active and less likely to smoke.

Researchers found that the more optimistic people were, the greater their overall physical health.

The most optimistic people were 76% more likely to have health scores that were in the ideal range.

3. Conscientiousness

Men with conscientious personality traits and those who are open to experience live longer, a study has found.

For women, those who are more agreeable and emotionally stable enjoy a longer life.

This means that for women the best personality traits for a long life are:

1. Extroversion
2. Optimism
3. Agreeableness
4. Emotional stability

Whereas for men, the best traits are:

1. Extroversion
2. Optimism
3. Conscientiousness
4. Openness to experience

Ask your friends how long you will live

The kicker is that it’s your friends — not you — who are better at judging these personality traits from the outside…

…and consequently predicting how long you will live.

Dr Joshua Jackson, the author of a study on the subject, said:

“You expect your friends to be inclined to see you in a positive manner, but they also are keen observers of the personality traits that could send you to an early grave.
[…]
Our study shows that people are able to observe and rate a friend’s personality accurately enough to predict early mortality decades down the road.
It suggests that people are able to see important characteristics related to health even when their friends were, for the most part, healthy and many years from death.”