When I was much younger, I always wondered why suddenly I feel so cold after taking supper (you can also call it dinner part-II). Within 20 mins from the moment I have finished taking supper, I start feeling cold. The only way I know to get rid of that situation is to jump under the blanket. I always wondered why that happens as I was under the notion that I put more energy in my body when I eat and I am supposed to feel strong and warm. I was slightly wrong. Here is why.
When you eat, a lot of energy is needed to digest the food properly. As a matter of fact, our body mechanism sends in a lot of blood to help that process. But body can't take blood away from the vital organs. So the mechanism borrows blood from those parts of the body which can still perform moderately with less blood. And our skin ("outer" surface) can perform very well with less blood except for the fact that lack of blood supply means less energy is being carried there. So there are fewer heat carrying elements. And we feel cold.
[pseudoscience: the information I write with the 'pseudoscience' title may or may not be correct. I simply write what I think and what I guess. The sole purpose I have is to analyze scientific issues in the simplest way possible. Trusting them is upon you.]