Satiation is the opposite of hunger and the body measures satiation by several different avenues; amount of chewing, the weight of food in the stomach, and the amount of stretch the stomach experiences as it fills with food. Unfortunately the signals from these different monitoring systems have about a 20 minute lag-time getting notifications to the brain.
Most people can sympathize with the following example: You had a first serving and didn’t realize that it was enough to satisfy you until 20 minutes later, by which time you already ate a second portion, which you won’t realize was too much until 20 minutes after that when you begin to feel uncomfortably full.
The best way to avoid overeating due to the 20 minute messaging delay is to stop eating when you are 80% full.
What does 80% feel like?
80% full is the place where you no longer feel hunger pains, yet you don’t feel full; you feel fine, you feel satisfied. At 60% and 70% your sense of hunger has decreased significantly since you started eating but is still slightly present. At 90% you feel full, and at 100% you feel stuffed (Thanksgiving Dinner).
Eating beyond 80% will likely result in fat storage as well as a slight numbing to your ability to accurately sense your body’s hunger and satisfaction cues in the future.