Well, that doesn't sound too hard!

Do five simple things a day to stay sane, say scientists - Times Online

5 Steps to happiness

1. Connect: Developing relationships with family, friends, colleagues and neighbours will enrich your life and bring you support.
2. Be active: Sports, hobbies such as gardening or dancing, or just a daily stroll will make you feel good and maintain mobility and fitness
3. Be curious: Noting the beauty of everyday moments as well as the unusual and reflecting on them helps you to appreciate what matters to you
4. Learn: Fixing a bike, learning an instrument, cooking – the challenge and satisfaction brings fun and confidence
5. Give: Helping friends and strangers links your happiness to a wider community and is very rewarding

More green funny business (although I can't vouch for the info in this article as I just sped-read it)

Blow to image of ‘green’ reusable nappy - Times Online

So hopefully when we know this we can do something about it?

Obesity, Abnormal 'Reward Circuitry' In Brain Linked: Gene Tied To Dopamine Signaling Also Implicated In Overeating