People are happier if they are able to feel emotions they desire - even if those emotions are unpleasant, such as anger and hatred, a study suggests.
The results of the study, compiled by an international team of researchers, found happiness is "more than simply feeling pleasure and avoiding pain".
Researchers asked participants what emotions they desired and felt.
This was then compared to how they rated their overall happiness, or life satisfaction.
The researchers found that while people overall wanted to experience more pleasant emotions, they had the greatest life satisfaction if the emotions they experienced matched those they desired.
The cross-cultural study included some 2,300 university students from the United States, Brazil, China, Germany, Ghana, Israel, Poland and Singapore.
"If you feel emotions you want to feel, even if they're unpleasant, then you're better off," lead researcher Dr Maya Tamir from The Hebrew University of Jerusalem told the BBC News website.
Surprisingly, the study also found 11% of people wanted to feel less of positive emotions, such as love and empathy, while 10% of people wanted to feel more negative emotions, such as hatred and anger.
Dr Tamir explained: "Someone who feels no anger when reading about child abuse might think they should be angrier about the plight of abused children, so want to feel more anger than they actually do in that moment."
She added that a woman who wants to leave an abusive partner but is not willing to do so may be happier if she loved him less, for example.
'Feeling bad can be good'
Dr Anna Alexandrova, from the University of Cambridge's Wellbeing Institute, said the research challenges how people think of happiness.
This study nicely calls into question a traditional measure of happiness that defines it as a ratio of positive to negative emotions, she said.
But when it came to unpleasant emotions, this study assessed only anger and hatred, which Dr Alexandrova said is a limitation.
"Anger and hatred may be compatible with happiness, but there is no indication that other unpleasant feelings, such as fear, guilt, sadness and anxiety, are," she said.
Prof Tamir said the research does not apply to those with clinical depression: "People who are clinically depressed want to be more sad and less happy than other people. That only exacerbates the problem."
She said the study sheds light on the downsides of expecting to always feel happy.
"People want to feel very good all the time in Western cultures. Even if they feel good most of the time, they may still think that they should feel even better, which might make them less happy overall."