Everyone wishes others a "Happy Holiday", but I am going to take it a step further and wish all a Healthy Holiday.
Thanksgiving is an example of our, as a society, gluttonous nature at its max. How many times have you heard someone say tomorrow (the day after Thanksgiving) I'm going on a diet?
But it's not just the excess that is so unhealthy, it's what is being eaten. It's not as if the majority of people eat healthy 364 days a year and then let loose on 1 day; unfortunately most people eat far too much processed foods high in fat, refined flowers and sugars, and then look at Thanksgiving as a free pass to eat more of the same but in excess.
Most of the Thanksgiving favorites are those dishes full of heavy cream, butter, refined flower, and lots and lots of sugar. If all that was eaten was a meat (the turkey), a starch (the potato minus all that butter and cheese), and a vegetable (minus any that isn't) along with gravy made only from the juices on the turkey then you wouldn't have to feel so guilty when you eat that piece of pumpkin pie...
You can enjoy the holiday and eat healthy at the same time without sacrificing much at all. Limit your plate to a normal size portion making sure to reduce the amount of refined flower and sugar on your plate as well as the alcohol you drink... and eat slowly (some conversation during dinner helps there), and then wait a good 30min before going back for seconds (once again "conversation" is your best ally). That way you will allow your stomach some time to digest your first plate-full giving your brain a chance to get on the same page with your full belly.
By limiting the amounts of refined flower and sugar you will prevent your blood sugar form spiking and by eating slowly you will allow your stomach to begin digesting. If you still want seconds you will most likely be fuller than if you woofed down your first helping, greatly reducing the chances of you diving back in with hungry eyes.
Add a little more conversation between those seconds and desert and I can assure you, you wont be looking at that smorgasbord of deserts like an oasis in the middle of a desert.
Have a healthy Holiday!