The Food Programme on Radio 4 this afternoon was about how being in contact with where their food comes from makes people measurably happier. They interviewed the academics who are doing the research along with a variety of people who rent apple trees and get to pick the fruit, allotmenteers, and members of a CSA food scheme where people part pay for their meat and veg by doing a bit of weeding or packing. http://www.bbc.co.uk/radio4/factual/foodprogramme.shtml
It is a good idea - but then all the people interviewed had ample leisure time, were increasingly fit due to all that digging and had enough spare cash to pay for all their apples in advance. These things would all help on the road to happiness I think.