Colonist nutrition

I couldn’t find it documented in the Rimworld Wiki, but it appears that humans require 1.6 units of nutrition per day. Since both simple and fine meals provide 0.9 units of nutrition, they eat two meals per day. In a normal maintenance scenario, the extra 0.2 units of nutrition is wasted. But when the pawn is below full food saturation, the extra units of nutrition allow them to catch up.

Ok, after further research, the 1.6 units of nutrition per day is roughly accurate but not the whole picture. Here’s the basic rundown:

  • All needs are a scale from 0 to 100, expressed in the needs view as a percentage
  • The absence of the food need is called “saturation”
  • Saturation decays every tick at a variable rate, but when well-fed it is 160 units per day
  • One unit of nutrition creates 100 units of saturation
  • So a simple meal, that contains 0.9 nutrition (or 90 units of saturation), will fill an empty food need 90% of the way to full

Non-humans have a “hunger rate” that is a multiplier of the human saturation decay:

  • A muffalo with a hunger rate of 0.85 would have a normal saturation decay rate of 136 per day and require 1.36 units of nutrition
  • A chinchilla with a hunger rate of 0.30 would have a normal saturation decay rate of 48 per day and require 0.48 units of nutrition

Since animals eat mostly raw foods which all have a nutrition value of 0.05. This means that the number of raw food items per day required to keep a single animal fed is:

\begin{align} i & = \frac{160 \times h}{5} \\ i & = 32h \end{align}

where:

  • i is the number of items of food
  • h is the animal’s hunger rate