Take a look at the table below to determine how many calories a typical male needs. For women, subtract about 200 calories. 

You will notice that up until age 20, we will require more and more calories. But then our metabolism starts to slow down. By the time men reach their 50s, they rarely require more than 2200 calories per day if they are sedentary.

How much do we actually eat? Take a look at the below graphic to get an idea of how many calories we think we eat, compared to how many we actually eat.

As you can see, most people think that they only eat about 1000-1200 calories per day, while really consuming 2000-2500 calories per day.

Further, most people severely underestimate the amount of calories they actually burn.

Let's be realistic and realize how much we are really eating and how much we are burning. Do we really need all those calories?