Went to a thanksgiving celebration the other day. There was loads of food of course, so I thought well I could eat everything but then I realised. I do not necessarily need to eat so much. That's why we eat large portions, because we do not think about the possible and excess calories we could be putting into our bodies.
Overall the more eat, the more unnecessary weight we can be putting on.
So eat when we are hungry, and try not to eat far too much large amounts of food.