The pursuit of happiness is a modern phenomenon that, you could argue, may not serve to make us happier at all. If the self-help book category is anything to go by, we are a bit obsessed with being happy.
But I wonder if we really know what "happy" means. And how do we know happy when we haven't been sad?
Perhaps we need light and shade in life.
You could apply this same thinking to health. The dogged pursuit of good health, to the point of obsession, may cause more stress than it solves.
And there's nothing like a bout of ill-health to make us appreciate that feeling well is not a given. Being human, we take health for granted. We toddle along, feeling fine, not caring much, until something wallops us and we wish we'd paid attention when we had the chance to eat better or get fitter.
We are not great at taking action now to solve theoretical future problems.
We tend to respond better to immediate gratification than to long-term payoff.
Which is why new research about health, happiness and vegetables offers great news.
Researchers at the University of Warwick in the UK have found eating more fruit and vegetables can substantially - and quickly - increase people's happiness levels.
Happiness benefits were detected for each extra daily serving of fruit and vegetables up to eight portions a day. The researchers reported people who changed from almost no fruit and veges to eight portions a day felt an increase in life satisfaction equivalent to moving from unemployment to employment.
This study is one of the first times scientists have looked at the benefits of fruit and vegetables beyond what we traditionally know: that fruit and vegetables can reduce the risk of cancer and heart disease.
We all know about those long-term benefits, but because of that instant gratification thing, it's quite hard to convince people to eat more veges.
The benefit, though real, is in the future.
The great news is this study found feelings of happiness developed relatively quickly from eating fruit and vegetables. Within two years of starting an improved diet, the authors found "large positive psychological benefits" in the subjects.
Researcher Dr Redzo Mujcic said: "Perhaps our results will be more effective than traditional messages in convincing people to have a healthy diet.
"There is a psychological payoff now from fruit and vegetables - not just a lower health risk decades later."
It's great to see scientific proof for a positive health message - adding to your diet rather than cutting something. Those of us who eat lots of plants already know it makes us feel good, but now there's evidence.
I can feel my self-help book writing itself. Maybe the title will be Veg Out and Find Happiness. Or The Life-changing Magic of Vegetables.