Food is a representation of how fed you currently are. You will gradually become more hungry over time, but actions that consume Stamina or regain Health also drain your food. The more thermally insulated your character is will reduce your consumption rate. If your character is Cold and/or Injured, they will become hungry faster. If your Food reaches 0, you will Starve, draining your Health at approximately 1 hp per 5 seconds, and gradually increasing Torpidity. Food can be restored by eating Berries, Meat, Crops, Jerky, Eggs, or Custom Consumables.
At times, the Food-icon will turn pale/grey. When this occurs, your character is in the hidden "constipated" state and needs to poop. While "constipated," your character will lose food at a greater rate than normal, and any factors draining food will be amplified (i.e. get hungry more quickly). Pooping (default: + or + ) will cease this hidden status effect and your food consumption will return to normal. If left ignored, constipation will eventually reach its critical/breaking point and your character will automatically poop for you. If you do not properly manage your character's constipation, you could drain an entire Food-bar during one Stamina-bar regeneration; this is especially true for characters with high stamina. Sometimes, such as when Cold and/or Injured, your character may even need to poop 3 or 4 times in just a couple of seconds. So don't just press the poop key once and stop; keep pressing it! If managed properly, what would normally drain an ENTIRE Food-bar might only drain 30% leaving you with 70/100 food (and 2 or 3 human feces) instead of 0 food and Starving. This can be an incredible way to conserve your food resources because if you don't know about this trick or don't pay attention you will burn through food like crazy.
Note: Although tames show the same pale/grey food icon, they do NOT suffer the same food draining consequences as the player's character does. This means they do NOT get a hidden constipated status; they are simply ready to produce feces
Putting a point into Food increases your maximum Food by 10. This does not have any effect on the nutrition or food values of what you eat, but allows you have more digested food at once, which therefore takes longer to deplete to 0.
When you eat food (excluding Rare Mushroom), your hunger is not immediately refilled. It instead gives you a hunger regeneration effect, the total amount of which depends on what you eat.
Eating more Food than your Food bar can hold will not hurt you, but it will not carry over either. It will simply waste food.
Some foods will constipate you more than others. Rare Mushrooms being the worst culprit (i.e. they make you poop a lot!), because of their instant food replenishment mechanic and its interaction with the hidden food saturation mechanic. Cooked Fish Meat and Custom Consumables are amongst the highest saturation (i.e. you rarely poop)
Some players never invest any points in increasing the Food stat at all. It is usually considered a low-priority stat, as food sources are plentiful and easily obtained in ARK.
You can also eat Raw (Food= +10 & Health= -5) or Spoiled (Food= +3.5 & Health= -12) meat, but this will lower your health and only provide a slight Food increase.
Enforcer is currently the only creature to have Energy in place of food.
When regaining stamina or healing, going prone can greatly reduce the consumption of Food and Water. This can be extremely useful in very cold or hot environments. This is also useful if you need to go AFK. Remaining prone while being idle can prevent you from starving or being dehydrated while you are away.