Christmas is to health what a sledgehammer is to kneecaps – likely to turn the whole thing into a pulpy and unsightly mess. The culprits are numerous: cold, booze, loneliness, congealing meat, damp, brandy butter, family arguments, icy pavements, open flames, late nights and sharp knives. Looked at that way, the standard yuletide shindig starts to sound more like a medieval test of strength than a midwinter holiday. But these tips should help you to get through to January without too much damage.

You don’t have to stuff yourself like a turkey

One Christmas, I watched a woman scream – actually open her mouth and cry out in pain and fear – at the amount of butter going into my grandmother’s cooking. There was an ashtray beside the Aga and a large sherry by the chopping board, so perhaps she had a point, health-wise.

When it comes to Christmas, eating is a marathon, not a sprint. Think of what you’re eating over the whole day, not just an individual meal. As the British Heart Foundation puts it: “A one-off celebration meal probably won’t make any difference to your health in the grand scheme of things, so enjoy it. However, if you’re having a few, try to scale back what you’re eating in your other meals.”

Also, remember that it takes about 20 minutes for your brain to catch up with your stomach and make you feel full, so perhaps build in a pause – even a walk or a game – between your main course and pudding.

Finally, as with the rest of the year, try to get as much fresh food, fibre, fruit and vegetables in your diet as possible. Maybe even try to eat them without cooking them in butter?

Cleanliness is next to healthiness

Want to avoid food poisoning? “For heaven’s sake, make sure you’re cooking food properly,” says Sarah Jarvis, a GP. “Even if you’re running late, do not be tempted to put a half-raw sausage on the table.” You must also separate raw and cooked meat and put ingredients back in the fridge as soon as you’ve finished with them. “Don’t leave them on the side for the next eight hours – very, very common – because that’s when germs multiply.”

Jarvis adds: “There’s often a huge increase in norovirus in the last two weeks of the year. Tummy bugs, the winter vomiting bug – all that.” These can be spread through food preparation. So, while it might sound obvious: wash your hands. “The faecal-oral route is every bit as disgusting as it sounds,” says Jarvis. “If you have a tummy bug, do not go near the kitchen for at least two days after your last symptom has gone. In fact, stay away from everyone else, too.”

You can avoid the Big Christmas Argument

For many of us, some sort of disagreement, shouting or squabble is as predictable a part of Christmas as pictures of robin redbreasts. The trick is to prepare yourself, says the psychotherapist Tina Chummun: “If you were to go into a big work meeting, you’d prepare for it. You’d write down your key points, you’d plan what you want to say, so you’re not thrown off when your body’s systems go into protection mode. When we’re going into a Christmas function with family, we have to put the same safety mechanisms in place.”

So if a relative is likely to do something that upsets you, have your strategy planned ahead of time. It might be counting to 10, changing the subject, reminding yourself of that person’s perspective, even leaving the room. If you know your brother will say something horrible at lunch, for example: “Think about that in advance. Tell yourself that he’s unhappy; that it’s about him, not you,” Chummun says.

Also, she suggests, practise the phrases you’re going to use, the words you want to say. “You could even say something like: ‘I love you. I don’t want to argue. Today is Christmas. I want it to be good. Let’s park this and I can come back to you when I feel safe and ready to talk about these issues.’”

Embrace the outdoors

How do you get up and move around when it’s so cold and dark outside? “I think it’s about being connected with what’s happening to the Earth,” says the psychotherapist Helen Edwards. “We’ve just come to the point of winter solstice before Christmas; the light’s just starting to grow again.” Rather than railing against cold and dark, we could try to focus on the change that is coming. “We’re through midwinter and now on this slow trajectory towards spring,” says Edwards. “Concentrating on that might help us with getting outside, sleeping, having calmness within.”

Of course, access to nature isn’t easy or equal for everyone. But if you can make it outside, there is beauty to be found. “The quality of the light is lovely in December and unique to that month because the sun is quite low in the sky. You might think of generic rain – grey, misty, cold – but there’s always a different character to that weather,” says Edwards. “Be curious: look at the way the seed heads are falling off the plants, the beetles under the bark of trees, the colour of the clouds.”

Take your focus smaller – to the fungi, puddles, decaying leaves – and cast your eyes up to the sky. “You can look at the moon every night. Or what time the sun comes up. Or just the way the clouds look; have that awareness of those greater constellations,” Edwards says. “People tell me that those things make them feel a little bit steadier. It’s like a scaffold.”

Do your bit to fight flu and Covid

“If you have been invited for a flu or Covid vaccine, then get it,” says Jarvis. “Unfortunately, we are now at the stage where it’s too late to be immune by Christmas if you haven’t had your vaccine, but it’s not too late in the bigger picture. Flu usually peaks around December and January, so it’s still a good idea to get a vaccine.” If you’re spending Christmas with someone who is clinically vulnerable, make sure any children in the house are up to date with their vaccinations, and if someone turns up at the door, streaming with snot and coughing like a newfoundland dog, politely ask them to come back another time.

Try to be your own best friend

Mind’s website has a section on dealing with Christmas, which is proof that anyone struggling with loneliness at this time of year is far from alone. “Try to avoid comparisons with the Christmas you see in adverts and social media,” the charity suggests. “These often do not reflect reality and can make us feel bad about ourselves. It may help to take breaks from social media.” Hallelujah to that. “Remind yourself that it won’t last for ever. You could set a start and finish time for what you count as Christmas.” Also, feel free to distract yourself, even with something as simple as a film or book set in summertime.

“Loneliness is really a disconnection with yourself, so try to be your own therapist,” says Chummun. “Writing things down is a release but it can also act as a reminder of what you’re struggling with.” If you see a regular therapist but they take a Christmas break, these notes might show you what you need to discuss when they come back. “If you don’t want to write it down, you can make voice recordings on your phone,” she adds. “Finding a safe space, on your own, and speaking your thoughts aloud can release that energy out of your body.”

Don’t get too merry

When it comes to Christmas Day, Jarvis has some salutary advice: “What’s really important is to avoid overdoing the alcohol early in the day. There are lots and lots of accidents at Christmas, and a huge number of them relate to cuts, burns and other things that happen in the kitchen.” If you’re going to drink, try to leave it until after the food has been served, and the dishes washed up and put away (or hidden in the sink). Make sure anyone a bit tipsy is kept away from the sharp, hot, spiky and smashable things.

Give sleep a chance

Sleep is hugely important for your immune system, and ultimately it’s your immune system that’s going to guard you against all the nasties that other people will share with you over Christmas. The Royal College of Psychiatrists’ tips include making sure that your bedroom and bed are comfortable (not too hot, cold or noisy), getting regular exercise, writing down anything that’s troubling you and, if you can’t deal with it right away, telling yourself you’ll deal with it tomorrow. Obviously you should avoid stimulants such as ecstasy or amphetamines, but don’t let the Christmas bingeing lull you into drinking too much caffeine (which lurks in some fizzy drinks as well as coffee and tea).

Finally, don’t be afraid to reach out

If you are feeling ill but are struggling to talk to a doctor, then out-of-hours pharmacists are trained to give out medication, treat minor illnesses and spot any red flags that indicate you might need more serious help.

You can also phone 111 or 999 as usual over the holidays, and call Samaritans any time, day or night, on 116 123, including Christmas Day. For older people and their families, carers and friends, the Age UK advice line is open from 8am to 7pm every day of the year, on 0800 678 1602.