December often sees a surge in our alcohol consumption—whether it’s an extra glass of mulled wine after a festive concert, shots and vibrant cocktails at the office party, or catching up with friends over drinks.

Suddenly, you might find yourself exceeding the advised weekly limit of 14 alcohol units within just a few days.

But does this occasional overindulgence really matter? To explore this, I decided to conduct a simple experiment. Though it lacked scientific rigor and wasn’t particularly challenging, it proved insightful.

For a week, I would drink more than the NHS-recommended maximum by attending a series of holiday gatherings and accepting every drink offered to me.

I didn’t set out to binge drink nor did I attend any events outside my usual December schedule. Essentially, I continued my typical December routine—darting between family gatherings and colleague meet-ups before the Christmas holiday.

The scientific part was that I didn’t drink for ten days before this merry bout of socialising and I underwent various medical, cognitive and physical tests at the start and end of it.

What I wanted to find out was whether as few as seven days of festive partying would make any difference to my health, both physical and mental. I would also keep a log of all the alcoholic drinks I consumed.

The experiments were conducted by a team at Hooke, a private clinic that specialises in anti-ageing treatments. Jean-Marc Sobczyk, one of the doctors there, who has spent time working at an alcohol addiction clinic in Switzerland, warned me beforehand: ‘Regular drinking or binge drinking – both are bad.’

His view is backed by Dr Samantha Wild, a GP at Bupa: ‘There is no safe level of drinking – you really have got to get that into your head. Even if you are drinking no more than 14 units, week after week, that’s not good for you.’

Yes, that feels like a Grinch-like attitude at this time of year, but for most men my age, it should also sound an alarm.

I’m 51 and became an adult at the time the chief medical officer recommended that men should avoid drinking more than 21 units of alcohol a week.

In 2016, that guidance was tightened to a maximum safe amount of 14 units week – but I am probably one of the 32 per cent of adult men in England who, according to the NHS, consume more than that.

Fourteen units may sound a decent amount; it is the equivalent of a touch over nine glasses of wine. But that is only true if those glasses are a standard pub measure (125ml) of a 12 per cent ABV (alcohol by volume) wine, which is the level of most white wines or light red wines.

Yet most bars (and indeed most households) would consider such a glass to be ‘small’. A large glass (250ml) of a heavy red wine can be 3.6 units. Four glasses of that and you’ve already hit your weekly limit.

The tests I underwent at Hooke included a ‘grip test’ – I had to squeeze the handle of a machine as hard as possible – which is an excellent way to ascertain your fatigue levels as well as your strength.

I also had to balance on one foot with my eyes closed, a way of finding out how likely I am to fall over as I age, as well as my general athleticism.

I wore an EEG skull cap, which recorded my brain’s electrical activity through electrodes placed on my scalp, while clicking a computer mouse every time I heard a beep, repeating numbers backwards and calculating the next pattern in a sequence. Plus, I had blood tests done. It was a full examination, lasting two hours.

Once finished, it was time to start drinking…

Day one

After a busy day at work, I rewarded myself with a spritz – some sweet vermouth with sparkling water. It’s a delicious and only moderately alcoholic way to start the evening – just three-quarters of a unit of alcohol. Unfortunately, it slipped down so easily that I had two as I prepared to go out to a Christmas party: ‘festive networking drinks’ hosted by the British Retail Consortium.

As a journalist, I get invited to quite a few of these types of events, and I knew there would be lots of people I had not seen for a long time as well as possible new contacts – a task made easier with alcoholic lubrication.

I drank three glasses of the white wine on offer: the ‘chicken wine’ by La Vieille Ferme.

It was also my eldest son’s 23rd birthday so we had arranged to meet later at a Thai restaurant close to my work event.

Foolishly, perhaps, I carried on drinking, having two bottles of Singha beer with my meal. By the end of the evening I was tiddly but not drunk.

Units: 11.2

Day two

By chance, I had to interview a man who runs co-working spaces – communal offices – in London, Paris and Berlin, which attract workers by offering free coffee in the morning and free beer after 3pm. The company, Beyond, says alcohol gives people a reason to commute into an office. Anyone can pour themselves a glass of beer from the tap.

The boss insisted I join him for a drink – just a small glass – at 4pm.

I then went to a Christmas concert at the school of my youngest son, Arthur, who was performing.

It’s a big festive event with lots of Santa hats and cheese and biscuits as well as wine laid on for the parents. I partook (but not in the Santa hat wearing).

Units: 7.9

Day three

A Friday evening and Arthur’s 14th birthday. He had some friends over after school and my wife and I took them to the local pizza restaurant, where we had a couple of glasses of wine each.

Back home, while the boys played computer games, my wife and I watched a (not very good) Diane Keaton Christmas movie, The Family Stone. I took the edge off my disappointment with a double whisky.

Units: 7.1

Day four

A busy day: a morning run, a trip to the tip, buying the Christmas tree, rooting around the attic for baubles, untangling the lights, which required a deep breath and a sloe gin.

Then in the evening I went to a Christmas party hosted by a former colleague who is now a neighbour.

I was fairly tired (the alcohol or just a busy week, hard to say), so I wasn’t really in the mood. But, as so often, after the first glass of wine, I had a lovely time and enjoyed catching up with people I had not seen for a long time.

I drank too much and stayed too long.

Units: 12

Day five

Sunday and I felt the worse for wear, so thought I’d give myself a day off the alcohol. Dr Wild says: ‘We tell patients who drink to have a good three or four days off from drinking a week, because we want their liver to recover.’

But my wife (who had been sensible the day before) opened a bottle of wine and I joined her for one glass.

Units: 2.1

Day six

A Monday and a long day of work.

I have been wearing an Oura ring, a wearable fitness device, which measures heart rate and the quality of your sleep, among other things. When I woke up it told me: ‘Time to ease up. Your resting heart rate shows that you might not be fully recovered. To help recharge your energy levels, take it easy today.’

I took this advice and gave myself a day off from drinking.

Units: 0

Day seven

I adore the music of Radiohead, a band I have listened to since I was a student 30 years ago.

When they announced they were touring for the first time in seven years, I was desperate to buy tickets – but failed to get any for their UK shows. Instead I got some for one of their dates in Berlin.

Arthur is even more of a fan, and the tickets were his surprise birthday present.

I attempted to make the flying 18-hour trip educational (to justify taking him out of school for the day), so in the afternoon we visited the Berlin Wall, as well as an excellent museum chronicling life in East Germany. We then toured a Christmas market. He had a hot chocolate and crepe; I had a warming Gluhwein.

Like most of the fans, we arrived early, an hour before the concert. I got overexcited and had two pints before Radiohead had even started. I bought another in the brief interval before the encore.

A final indulgence in an indulgent week.

Units: 10.7

Total units for the week: 51

The results

It was only after the end of the week that I tallied all the alcohol units and discovered that I had consumed 51.

I was genuinely shocked.

I knew I had drunk quite a lot, well over the NHS recommended limit, but at no point did I feel as if I was properly drunk. Nonetheless, I had what many doctors would consider a dangerous amount of alcohol.

But how did this festive excess affect my health? I went straight to Hooke to find out.

First the good news: my blood tests indicated that my liver enzymes were ‘all comfortably within the healthy range’, meaning there was no obvious short-term liver damage, despite the heavy alcohol load.

The physical and neurological testing, however, showed that my week of drinking had caused a significant decline in my physical and mental capacities.

At the start of the week I could grip 39.7kg in my left hand; this had dropped to 34.3kg seven days later, which the report said suggested ‘reduced muscle activation and overall fatigue’.

I found the test when I had to balance on one leg with my eyes closed hard enough after ten days of sobriety, managing just ten seconds on my left leg. But this fell to a mere three seconds after my week of drinking.

The time it took to click on a computer mouse when hearing a series of beeps in my headphones went from 238 milliseconds to 353 milliseconds. The doctors said this result showed ‘reduced alertness, slower brain processing, and poorer motor response’.

My ‘after’ results for deciphering codes, patterns and repeating strings of numbers backwards all worsened, too.

‘Memory function and processing speed dropped, indicating poorer short-term memory and speed of processing when completing tasks,’ I was told.

Finally, my heart rate dipped slightly from 70 bpm to 61 bpm, ‘likely due to alcohol’s short-term dampening effect on the nervous system rather than improved fitness,’ the doctors concluded. Alcohol can affect the heart rate in several ways – speeding it up and potentially causing palpitations in the short term, as you drink, or acting as a depressant on the central nervous system and temporarily slowing it down, when you consume a large amount.

In short, just one week of fairly routine Christmas party activities had dramatically hit my ability to think clearly and to function on all cylinders.

The data from my Oura ring showed I often slept worse than normal. Not only that, my ‘Readiness score’ – a measure of how well recovered you are after each night’s sleep, and a proxy for your overall resilience, fitness and stress levels – had fallen from an average of 90.5 out of 100 during my ten days of sobriety to 73 during my week of drinking.

I was less good at concentrating and focusing. I was weaker in terms of strength, and my core stability had decreased, making me more likely to fall and significantly ageing me in general.

I was less fit both physically and cognitively. My brain had aged, though hopefully not irreversibly.

Dr Sobczyk says: ‘If we were being purists, we would drink zero alcohol. Why? Because it affects our brain health and as we get older we need to protect our brains.’

Will I give up booze? No, I enjoy it too much. But this has been an important wake up call. 

I will try to say ‘no’ to that second and, certainly, that third drink when out at a party.