THE festive season is meant to be a time of guilt-free indulgence, but when a few days off your healthy eating regime at Christmas becomes a month-long excuse to eat and drink what you want, it could spell bad news for your waistline.

With Christmas celebrations getting earlier and earlier, and a myriad of treats, social occasions and parties to tempt us off course, it can sometimes feel like an impossible task to stay healthy in the run up to Christmas Day.

Terri Ann, founder of the Terri Ann 123 Diet Plan, believes it does not have to be this way.

She said: “Christmas is a time to celebrate with friends and family, and of course we should all enjoy our favourite foods and spend time with loved ones at this time of the year.

"The problem starts when you start over-indulging too early in December, and use the festive season as an excuse to binge on food and drink that would usually be an occasional treat.

"This approach can very easily result in weight gain, and it makes it all that harder to start a healthier lifestyle in January.”

Here, Terri-Ann shares a few indulgences that could be knocking you off course, and how you can still treat yourself without piling on the pounds this December.

Advent calendar treats - up to 5,184 extra calories a month

A chocolate advent calendar is one of the best parts about December, but with a range of novelty advent calendars now on the market, many of us are no longer treating ourselves to just one mini chocolate a day.

A gin or beer advent calendar, which treats you to a bottle of your favourite tipple behind each door could see you knocking back an extra 137- 216 calories a day, while food advent calendars, such as cheese calendars, adds up to an extra 2,160 calories over the month.

While these advent calendars can be fun, a traditional chocolate calendar is actually better for your waistline - coming in at just 20 calories a day - so is actually the healthier option if you want to stay on track with your diet this Christmas.

Christmas drinks - up to 3,990 extra calories a month

There is no escaping the fact December is a boozy month, but do you know how many calories those extra drinks are adding to your daily intake? Whether it’s the Christmas party, a catch up with friends or a bottle of wine with Christmas lunch, alcoholic drinks soon add up.

If you go out twice a week during the run up to Christmas, and drink every day from Christmas Eve to Boxing Day, you could soon put away an extra 3,990 calories, depending on what your tipple of choice is.

Christmas coffees - over 4,184 extra calories a month

From gingerbread lattes to salted caramel hot chocolates, coffee shops pull out all the stops to tempt us with their festive drinks specials. But, be warned - swapping your usual coffee for a Christmas themed drink could lead you to piling on the pounds this Christmas.

Even if you only drink two of these special Christmas coffees a week, this could add up to a whopping 4,184 calories over the month.

Festive lunches - up to 19,952 extra calories a month

Whether it’s a pub lunch with work colleagues or a long awaited catch up with a friend, we all know that it’s not just one festive lunch you’ll be expected to have in December.

Eating out can be a big obstacle when it comes to achieving a healthy diet, with a lack of transparency on menus, restaurant cooking techniques and a lack of healthy options making it difficult to make balanced choices.

You might be tempted to order the traditional turkey on many restaurant menus this Christmas but, with the average turkey dinner coming in at 2,128 calories, if you eat out twice a week this festive season, you could soon put away an extra 17,024 calories a month.

Add on a dessert or starter and it soon adds up to 19,952 calories over the month.

If you know you’re going to be eating out multiple times this December, try to go for the healthier choices in at least some of your meals.

Try soup for a starter rather than deep fried items, and go for lower carb options for your main for a lighter option.

Christmas treats - up to 2,604 extra calories a month

In the run up to Christmas, the shops are full of sweet treats, and whether it’s in the office or out and about, it can feel like mince pies, chocolate and other festive treats are offered to you at every turn.

The constant temptation, as well as the knowledge that festive treats are only on sale for a limited time, can easily lead to food items that would usually be an occasional treat, being consumed multiple times a week.

A little bit of what you fancy won’t hurt, but it’s important to be aware of the calorie content of these indulgences and how they might be impacting on your daily intake.

As an example, if you eat three mince pies a week in the lead up to the festive period, this could lead to an extra 2,604 calories being consumed in a month.