Maximum regeneration duration (100%) is 1200 seconds in game.
Several combinations can be used to achieve maximum or near maximum fullness which is useful for bedmages for example 3 ham and 1 white mushroom/corncob gives 99 mana.
Sleeping will grant you up to 100 mana and 100 HP over 100 minutes (1h40), regardless of class.Is there a timing issue with reaching 100%?(TBC).
Characters dedicated to making runes this way are called bedmages. Characters dedicated to making runes generally are called makers.
Brown mushrooms are the best low weight food, costing 10g in Edron magic tower, weighing next to nothing and giving regen between a ham and a meat.
Hams are the cheapest food source but are heavy to carry. If you are not near a house or depot but want cheap food it can be beneficial to have multiple food sources i.e. cheap food you eat first and expensive food as a back up if you are out longer than expected.
Some foods strike a good middle ground between regen/price and regen/weight, such as bananas. These often have lower regeneration and need more clicks which can be annoying.