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If you are lonely, you will probably die earlier than other people. If you are unhappy, you need to exercise more. Chocolate won't help.
If you are saddened, frustrated or angered by that information, perhaps you should eat more fruit.
Emotions and their causes - and the things you can do to make unpleasant moods go away - were the subject of an International Science Festival panel discussion in Dunedin yesterday.
The event filled the Hutton Theatre, almost 90 people turning up to hear the thoughts of University of Otago department of psychology researcher Dr Tamlin Conner and visiting University of North Carolina professor Paul Silvia.
Hosted by Dr Christine Jasoni, the event heard sleep, exercise and diet were three major factors in keeping the ship of emotion in calm waters, although genetics played an important part in people's emotional make-up.
And the world needed both people who spent time worrying about the future, and those who did not - they just ended up with different jobs.
''You don't want to be happy all the time,'' Dr Conner said.
''Some times, you need to be stressed, and need to be anxious.''
But if that was an issue, Prof Silvia said there was ''an enormous amount of research'' showing people who were more physically active were happier.
Dr Conner said communing with nature, and with other people, and eating well, were also shown to help.
''Walk to work through the botanic garden while eating fruit and engaging with friends.''
Studies had shown loneliness, on the other hand, led to an earlier death.
''Loneliness is a really strong predictor of early death,'' Dr Conner said.
''Not only does being with people make you feel good, it's good for you,'' she said.
Prof Silvia said an experiment in which people were required either to eat a chocolate bar or go for a walk found those who went for a walk ended up happier.
''People who went for a walk perked up,'' he said.
Exercise led to a lift in mood that was ''more durable and longer lasting''.
Dr Conner said another thing that helped on the happiness front was developing an active interest.
That could be as simple as developing an interest in a movie genre, and seeking out examples to watch.
The more challenging the interest, and the more effort involved, the more sustainable the happiness that resulted.
The discussion ended with some good news - people became happier as they aged.
Older people - particularly those over 65 - were better at managing their emotions, and staying away from activities they did not enjoy.
''It gets better,'' Dr Conner said.