Q: Is winter weight a thing? 

A:  Yes, and no. Humans have a set weight range that is determined by their genetics. 

While activity levels and food intake can affect these, your DNA usually dictates how much fat your body retains; unless you are doing something excessive to either gain or lose weight. 

There is, however, some truth to being exposed to extreme cold that causes a temporary rise in body fat called "brown fat". 

This is easier for your body to burn and is used to make sure that you maintain body heat. This fat burns quickly and is unlikely to be the reason for weight gain. 

However, with the holidays and the low  temperature, people tend to eat too much and exercise too little. This is the main reason for the extra pounds gained during the cold season.

Q: Is there anything that can be done to prevent it?

A: Keeping up with your regular exercise year around will help circumvent this. The Center for Disease Control recommends that 

the average adult participates in at least  2 hours and 30 minutes of moderate activity or 75 minutes of high intensity activity every week.

Keeping tabs on what you eat will also help. It's tempting to binge during the winter months with all the parties and holidays, but 

some things should be enjoyed in moderation. There is no shame in indulging every now and then, but eating over 4,000 calories 

a day will catch up to you if you’re not doing the extra work to burn it off. 

If your area experiences extreme cold, try taking an indoor exercise class during the winter months. 

Variation in your routine can help you from plateauing in your fitness goals. 

Always consult your doctor before starting any exercise program.