Most of us would think that filling our bellies would leave us satisfied.
So, why, after a late night biscuit binge or a ginormous burger lunch do we still want to eat more?
Before you write yourself off as greedy, science may have an explanation that might make you feel slightly better about yourself.
A new study by researchers at the University of Vermont has revealed that we might be psychologically conditioned to want seconds, even when we feel physically full.
Turns out that when we associate fullness with having more food, it can actually make us feel even more hungry.
The 12-day-long study was carried out by Dr Mark Bouton and Dr Scott Schepers on 32 rats.
In the first test, the rats were placed in a box in a satiated state and learned that they would be fed treats if they pressed a lever inside the box.
Then the rats were placed in the same box when they were hungry, but pressing the lever no longer produced treats.
Therefore, the rats began to associate fullness with receiving treats and hunger with an absence of food.
When the experiment was repeated, the researchers found that the rats pressed the lever more frequently when they were full than when they were hungry.
“Rats that learned to respond for highly palatable foods while they were full and then inhibited their behaviour while hungry, tended to relapse when they were full again,” Bouton explained.
This relapse pattern emerged even when food was removed from the cage before both the learning and unlearning sessions, indicating that the rats’ internal physical states, and not the presence or absence of food, cued their learned behaviour.
The results could indicate that the idea of getting food when we’re full could be a stronger impulse than actual feelings of hunger.
So next time you reach for that second slice of cake after a whopping great roast with all the trimmings, don’t beat yourself up about it, science made you do it. Sort of.
Read more from Yahoo Style UK: