This time of year it's always the same story: too much good food and not enough exercise.
Even if you indulge only occasionally in mashed potatoes, bread, dessert and calorie-filled alcoholic drinks, it's still enough to increase your body fat.
Many people gain a kilo or two during winter - but there are seasonal things you can do to help you stay in shape.
Winter's cold weather alone makes you burn extra calories to stay warm. You can use the season to lose fat, and also add techniques to keep your appetite in check so that you bounce into spring without gaining even half a kilogram.
Here are some tips:
Go for a quick jog outside without enough clothing: A 10-minute run on a cold day without a jacket will force your body to produce heat faster. As you move your arms and legs, you'll be burning calories at a higher rate. Even shivering will help you burn extra calories.
Don't overdo it - 10 minutes outdoors in chilly weather will boost your metabolism and burn a lot more calories than just walking around inside. Do this in the morning, rather than before bedtime. The extra calorie burn will last for most of the day.
Fill up before a party: Parties offer many fattening treats and drinks. Curb your appetite by taking its edge away.
Eat a snack of low-fat protein - such as a few slices of packaged deli turkey - about 15 or 20 minutes before entering the party.
Make your stomach feel full with a veggie snack - something like a dozen or so baby carrots; in fact, buy a big packet of tiny carrots, and repackage them into small plastic bags that you can carry them with you. That way, whenever you feel hungry, you've got something healthy and filling at hand - making it easier to resist the chocolate cake.
Use hot water for eating emergencies: Just before sitting down to dinner or being exposed to a table of treats, drink a big glass of hot water or artificially sweetened tea. The hot liquid fools your appetite into feeling satisfied. You'll eat or drink a lot less after swallowing a warm drink.
Wait for food to catch up to your appetite: There's a lag time between eating and feeling full, which is why you can eat so much that it actually hurts. Make a deliberate practice of eating slowly. Start with much smaller portions than you want.
Take a few minutes after cleaning your plate before grabbing a second helping. What this does is minimise the time between your desire for food and the feeling of satisfaction that comes from eating.
Which leads us to the final and most important part of not gaining winter weight: Don't eat if you don't feel hungry.
We're all so accustomed to the social act of eating that it becomes almost automatic - and that is the main source of winter weight gain. So before putting anything in your mouth, think about it. Do you really want that lolly? Are you truly hungry for those bits of cheese or slice of ham? Are you loading up on appetisers or biscuits just to have something in your hands?
If you don't really feel an urge for food, don't take any. If you use your head instead of your eyes, it becomes much easier to resist taking in calories that you really don't want - either now, or later, when they come to rest on your hips and thighs.