The science

good, driving individuals to work harder, smarter and longer, but it can have a toxic impact on a person’s life.

Happiness researcher Andrew Oswald, from the UK, found the intensity of a person’s envy is associated with a slower growth of psychological wellbeing as their life goes on.

Cutting envy may mean toning down your social media use, and exposure to advertising.

Adverts tend to show happy people, with their happiness linked to the consumption of products or services, or the ownership of an item such as a car or new clothes. Oswald, in a joint project with other researchers, found increases in advertising spending within a country led to declines in life satisfaction.

International research has established that the depth of a person’s social connections, and whether they have people to call on in times of trouble, is important for happiness.

Marriage, and stable, longterm relationships, are predictors of happiness.

Harvard University has run one of the longest studies on a group of people. Starting in 1938, Dr Arlie Bock studied a cohort of 268 Harvard graduates, and 456 men who grew up in inner-city Boston.

He found health and education were very important, but concluded: ‘‘Warm, intimate relationships are the most important prologue to a good life.’’

Social support also comes from outside the home. And, as recent research from the Pew Foundation in the US found, it can come from being active in religion.

This was an effect that was also measurable in New Zealand. Simply being religious did not seem to be associated with higher personal happiness. It was being ‘‘active in a congregation’’ that was linked to greater personal happiness.

The Pew Institute stressed this finding could be interpreted in different ways. People who were active and healthy might be more able and inclined to participate in religious congregations, for example, than people who were unhealthy and disengaged with their local communities.

Health is one of the most influential predictors of happiness, research shows, and while New Zealand may score highly for obesity, we do have long health expectancies compared to many other countries.

Exercise is important, but being super-fit is not.

The available evidence supports the idea that people who are active and physically fit are at a lower risk of developing depression.

In April, the Journal of Happiness Studies did a huge literature study of research into the link between exercise and happiness.

It concluded: ‘‘All the observational studies reported