There are various ways of reducing Food Consumption without reducing the amount of Units you maintain. This can be achieved by building certain Buildings, acquiring certain Items, and mastering Abilities that affect Food Consumption. The formula for calculating Food Consumption Reduction is as follows:
Firstly, the Food Consumption statistics of all your Units are added together. The resultant number is your Castle’s Base Food Consumption.
Following this, the reductions from the Spring of Life and the Food Consumption Enchantment at the Obelisk of Power are applied to Base Food Consumption. These percentage reductions are added together and applied as one reduction, rather than applied cumulatively in sequence. This creates Adjusted Food Consumption.
The following reductions are then to Adjusted Food Consumption: Hero Abilities, League Knowledge, Consumption Reductions from high-Level Farms, and Food Consumption Reduction Items. These items are applied one after another, meaning that the number affected is the number resultant of the previous reduction, not the Adjusted Food Consumption calculated from the first stage.
This resultant total is your Castle’s Actual Hourly Food Consumption.