How many % of human energy is spent on digesting cold food. Is there differences in eating cold and warm?

Answer 1

I have never seen any figures, but I do not think it takes any more energy to actually digest cold food than warm food. It is all the same biochemical reactions and mechanical activity in the stomach and intestines.

There is probably some slight theoretical lose of body heat to the cooler food. But I think it would be of no more consequence than drinking a cool glass of water..