There is theory currently being tested as to wheither or not we humans actually hibernate. The common connotation is that hibernation relatest to our understanding that the “long-sleep” is intended for recover and preservation in mammals such as in bears during winter season. However with us humans it doesn’t seem to be the case.
If you’ve ever noticed that you gain more weight during Christmas season is not due to the food that you normally consume but rather due to your lowered rate of metabolism that your body undergoes during the cold months, this is our body’s adaptation to the environment where we live and it varies in countries that do not have snow, but relatively speaking it applies to all humans in general; that is why its harder to tone down during winter.
Don’t be alarmed just remember that If you plan on maintaining your weight its not just your diet you have to look into controlling you have to exert a bit more effort than you normally would in exercise during normal months if you want to manage your weight that is.