Is a full fridge more efficient?

What is the most energy efficient setting for my home fridge & freezer, yet still keep the high life for food?

• I have a thermometer in both. Fridge is 38 degrees and freezer is 20 degrees. Would I save energy if these numbers were a bit higher? (But of course I do not want to lose food early either)

• Answer:

  Usually each one comes with the booklet which tells us. I keep my own on the dial provided inside it, at 3+ and the freezer has it's own dial. If after adjusting it one way or the other notice if frost accumulates in the freezer, *(then go down a bit,) & if the eggs seem to freeze; put it down to the 3 mark, & then check for the box area, (beneath where the majority of milk, foods go) make sure ,that stuff dose not freeze.