Christmas really can be the worst time for putting on weight, the calories just seem to creep into our diets; hot chocolates appear on our lunch breaks, fried foods do the rounds at the office party and then there's the worst culprit of all - the box of chocolates.

According to dietitian and Operation Transformation expert Aoife Hearne, each individual chocolate comes in at a heavy calorie cost. Watch the full interview with Aoife Hearne in the video above.

"I would say, the biggest pitfall for people is the boxes of Roses, Heroes, Celebrations - whatever - they are literally everywhere, you'd nearly see them in your dentist's office coming up to Christmas.

"We know that each sweet is 50 calories, right? So, if you're only having ten a day - which is a very conservative estimate - that's 500 calories, that's an extra meal in the day."

"People are having ten, 20, maybe 30because they're picking mindlessly at them, so again, the message comes back to be connected with what you're eating but really to pick your treat and enjoy it but don't mindlessly munch through two meals worth of eating without realising it"

Operation Transformation returns this January 

To put that into perspective, it would take five full minutes of intense exercise to burn off fifty calories.

That's five full minutes of running for just one measly chocolate! 

Operation Transformation returns to our screens on Tuesday, January 2nd on RTÉ One.