I went looking for the "fullness scale" that I used when I was doing Weight Watchers and I found this, which is more detailed and has lots of info:
From the Duke Diet & Fitness Center
The Hunger/Fullness Scale was developed by Barbara Craighead, PhD, to help people gauge their hunger to determine whether they need to eat or not. The next time you feel hungry or finish a meal, take a moment to rate your feeling of hunger or fullness on the scale
1 – Very Hungry
2 – Moderately Hungry
3 – Mildly Hungry
4 – Neutral
5 – Mildly Full
6 – Very Full
7 – Much Too Full
(The desirable zone is 2.5 to 5.5)
Here’s a little more about what the numbers mean:
1: Very hungry; starving; desperate. Your stomach is “screaming.”?
2: Moderately hungry; ready to eat. Your stomach is “talking.”?
3: Mildly hungry; beginning hunger. Your stomach is “whispering.”?
4: Neutral. You feel no sensations of hunger or fullness.
5: Mildly full. You feel satisfied.
6: Very full. Your stomach is beginning to feel a bit distended.
7: Much too full. Your stomach feels stuffed.
This is a subjective scale — it isn’t objective in the way that counting calories is. For that reason, it can be more difficult to use. However, continued focus and practice will help you become more sensitive to your body’s signals of hunger and fullness. Here are some tips:
• We recommend staying between 2.5 and 5.5.
• Never allow yourself to get down to 1. Have healthy snacks planned in advance and eat one if you fall below 2.5 on the scale. It typically takes three to four hours for the stomach to empty, so you should try not to go too much longer than that without eating.
• Stop eating at 5.5. Eat slowly — it takes 20 minutes for your brain to know your stomach is full.
Eating while watching TV is a huge overeating trigger for me, so I take a reasonable portion of whatever I want to snack on while watching something with DP and do not go back to the kitchen for more. No taking the whole bag of chips/container of dip/whatever into the living room.