We know that the concept of happiness is relative - if there was a one-size-fits-all quick fix to make us feel good then you wouldn't be reading this. But there are small things we can all strive to incorporate into our daily lives in the New Year to help improve our emotional wellbeing.
According to Dr Mo Zoha, consultant psychiatrist at Nightingale Hospital, there are some common causes of unhappiness common to most of us: "With my patients, I have seen an increase in work-related stress. Poor work-life balance is often a major aetiological factor in the development of unhappiness, resulting in people neglecting important areas of their lives, such as nurturing their relationships."
And it's not just important to stay happy for your mental wellbeing, Dr Zoha also notices a deterioration in people's physical health when they are unhappy.
He says: "On average, happier people are physically healthier, with fewer symptoms and episodes of illness and reduced death rates. They tend to be more optimistic, enthusiastic and enjoyable to be around and therefore more likely to have good families, friends and supportive relationships."
The most important thing is to understand what happiness is and, just as importantly, what it's not.
"Happiness is not just about experiencing hedonistic pleasure or positive emotions," he says. "Although they are important, our happiness is more linked to a range of other factors, such as our lives having a sense of purpose, participating in worthwhile activities, undertaking challenges and achieving goals."
Check out Dr Zoha's 12 tips for achieving happiness in 2015: