Four medium bananas are surprisingly filling because they're high in fiber and volume.

Approximate comparison:

Food Calories Filling (roughly)

4 medium bananas ~420 kcal High

2 plain pancakes (6-inch, no syrup/butter) ~300–350 kcal Moderate

Cheeseburger (fast-food size) ~300–450 kcal High

In terms of satiety:

4 bananas will usually keep you full about as well as or better than 2 plain pancakes, because they contain around 12 g of fiber and a lot of water.

Compared with a cheeseburger, it's more variable. The cheeseburger's protein and fat tend to keep many people satisfied for longer, even if the calories are similar.

So, if you're just trying to avoid hunger, 4 bananas are roughly comparable to a cheeseburger in immediate fullness, though the cheeseburger may provide longer-lasting satiety because of its protein and fat.

(http://www.autoadmit.com/thread.php?thread_id=5886336&forum_id=2#50024733)