I’ve gone completely overboard with New Year’s Resolutions this year. I’ve sworn off three illicit substances — alcohol, chocolate and ice cream — and vowed to eat an apple every day.

I’ve given up alcohol before. The first time was when I was living in New York in the 1990s, though the episode that prompted it happened in Switzerland. I got spectacularly drunk at a nightclub in Verbier and woke up the following morning without my signet ring. This was a family heirloom given to me by my mother so I was understandably distressed. It turned out I’d given it to a young Swedish woman who I’d proposed to the night before. I didn’t drink again until I got married, more than two years later — not to the Swedish woman, obviously. I never saw her again.

There are some advantages to not drinking. You lose weight, save money, work harder and sleep better. You feel more clear-headed, and I don’t just mean in the evenings, when you’d normally start drinking. Alcohol has an anaesthetising effect that lingers after the other, more tangible effects have worn off. At least, it does for me. After you’ve stopped for a few days, the mist begins to clear and you experience a kind of awakening. You feel fully in control of yourself in a way you haven’t for a long time.

At first, that’s a welcome change, but it isn’t long before boredom kicks in. One of the shocking discoveries you make when you become teetotal is the extent to which your moods are dictated by alcohol. Typically, I would wake up with a hang-over, full of shame and remorse, then, over the course of the day, my self-esteem would recover until, by 8p.m., I had no qualms about opening a bottle of wine. The first glass would produce a welcome flush of euphoria, my sense of contentment would peak at around 11p.m. and after that it would be a gradual descent into the Slough of Despond. Poor me, poor me, pour me another.

Without alcohol, you don’t have these ups and downs. You feel neither euphoric nor depressed. No intoxicating sense of freedom as your inner policeman is locked away for the evening, but no guilt and self-loathing either. It’s a flat line — one mood, all the time. Which is a bit boring, obviously.

Eventually, if you stick with sobriety, you become attuned to a different cycle and your sense of well-being does begin to ebb and flow again, but over the course of months rather than a single day. It’s hard not to feel nostalgic about the more dramatic mood swings induced by alcohol. You miss the rollercoaster.

I gave up again midway through last year, started again at Christmas, and have now sworn off it again. The reason I’ve added chocolate and ice cream to the list is because when I stopped drinking I immediately substituted one bad habit for another, eating a bowl of vanilla ice cream with homemade chocolate sauce every night. You develop a craving for sugar when you stop drinking and, as Caroline never ceases to point out, sugar is even worse for you than alcohol.

Unless it’s accompanied by plenty of fibre, which is where the apples come in. According to some research published last month in the British Medical Journal, if everyone over 50 ate an apple a day, 8,500 deaths a year in the UK from heart attacks and strokes would be averted. They have the same effect as statins, apparently, but without the side effects.

The other advantage of giving up chocolate and ice cream is that they will serve as a first line of defence if I’m tempted to become less abstemious. Instead of simply taking up drinking again, as I did in December, I can break one of my other resolutions. Worth a try, anyway.

To anyone who has an uncomplicated relationship with these simple pleasures, my self-denial may seem a bit weird. After all, it’s not as if I’m suffering from alcoholism or diabetes. Why not just enjoy life?

The answer has to do with my mother, who strongly disapproved of self-indulgence of any kind. She wasn’t a religious person, but her paternal grandfather was a Methodist missionary and his puritan blood flowed through her veins. I wouldn’t say I’ve inherited a full dose of this asceticism — just enough to counter-balance my epicurean appetites. At the age of 50 I’ve come to the reluctant conclusion that I will never be truly happy until I forswear pleasure of any kind.