It is estimated that the farmer uses about 20% of the energy used to produce the food in a grocery store. The other 80% is burned in the storage, transportation, processing, wastage and packaging by the distribution systems after the food leaves the farm.
Eating our food is not only healthy, it saves massive amounts of energy.
Since food production takes a large amount of the power (and water) consumed in the States annually, eating local food, grown and sold at a local farm, can save more energy than any other action you can take.