Ciaran Willis asks the experts to explain whether bingeing on sleep during the holidays does more harm than good

We all know Christmas is a time to slump on the sofa in front of classic festive films, argue with family over the TV schedule and drift sweetly into a mince pie coma.

More importantly though, it's also a chance to enjoy a much-needed break and catch up on all the sleep we've missed after the whirlwind work and party schedule of the previous months.

Experts tell us that it's beneficial to have seven or eight hours sleep each night, but we all know that life often gets in the way. Thankfully though, the relaxed lack of routine around Christmas - with the freedom to drink Baileys and stay in bed as long as we want the next morning - is a great time to even the score.

But while banking those extra hours might feel good at the time, it could actually have a negative effect on your health. Instead of not getting enough sleep, there's a risk of having too much.

How does oversleeping affect us?

According to physiologist Andrea Houston, oversleeping can have a negative effect on our circadian rhythm - the body's internal clock that makes us feel energised and drowsy around the same times every day.

She explains: "Oversleeping can impact the production and release of serotonin and melatonin, hormones that control things like mood, appetite, and our sleep and wake cycle."

Houston, who specialises in respiratory and sleep at London Bridge Hospital (hcahealthcare.co.uk), says that tampering with this can make us feel out of sorts, and can lead to bigger problems in the long run, such as depression, heart disease and diabetes.

Dr Nerina Ramlakhan, a sleep expert for Silentnight (www.silentnight.co.uk) says that too much sleep can also encourage bad lifestyle habits, which can contribute to low drive: "If you're oversleeping, you're less likely to be exercising regularly and eating healthily."

Sleeping for longer, she says, can actually be a source of fatigue in itself.

So, why exactly do we oversleep?

There are a variety of reasons we oversleep, but Dr Ramlakhan says that our mental wellbeing can play a crucial role.

"Mental health problems can have a big impact on sleep, as lacking motivation and purpose - along with low mood - can make it harder to get out of bed.

"Obesity is another factor," she adds, as "when people are obese, they are less likely to exercise, less likely to eat healthily and consequently are more tired.

"For some, Christmas can be a sad time, and there's a lot of pressure for people to be happy, which can cause low morale. Many people try to escape these feelings by oversleeping."

If oversleeping persists, it could be part of a medical condition, such as sleep apnoea, where a person stops breathing momentarily when they're asleep, or periodic limb movement disorder, where those affected have cramping and jerking of their legs during sleep.

Narcolepsy is another sleep disorder which can cause 'sleep attacks', where a person suddenly falls asleep, and it generally causes excessive sleepiness.

Though, for many of us, oversleeping can simply be a symptom of our all too busy lives. "An important factor in today's society is insufficient sleep, due to our work and social lives," says Houston, "which is why we may then try to play 'catch up' at weekends."

How can Christmas contribute to the problem?

Perhaps the biggest reason we oversleep during Christmas is the change in our routine, says Dr Ramlackhan. Insufficient sleep and an inconsistent pattern are the two main factors.

"Our normal routine becomes off balance in the Christmas hype," she says.

She adds that overeating - or getting stuck in a 'food coma' - as well as too much alcohol and socialising, can also play a huge role.

"Alcohol can affect our sleep architecture, causing us to have less REM sleep, the dreaming stage of sleep," says Houston. "This will make us feel drowsy, and we'll struggle to concentrate the following day."

How can I quit the oversleeping cycle?

It's understandable for everyone to want a break every now and again, as well as a few glasses of wine to celebrate the holidays. No one would begrudge that.

However, limiting oversleeping is a good way to avoid going back to work in January feeling worse than you did before the Christmas break.

Here, Dr Ramlakhan explains a few ways you can stay on top of your sleep this December:

1. Set some goals: "If you have New Year resolutions, now is the time to action them. Maybe these are health and fitness goals, or maybe it's about getting out into the fresh air."

2. Plan activities: "It's very easy to get stuck in a rut at Christmas, becoming bored and, ultimately, spending too much time in front of the TV. Planning helps us to keep focused and ensures our energy doesn't become stagnant."

3. Keep your mood up: "You can do this by exercising to reduce stress hormone levels, spending more time outdoors, exposing yourself to sunlight (it increases the brain's release of the happy hormone serotonin) and eating a balanced diet."