Sunday is the start of October, which means that people across the country will be attempting to give up bad habits; some will try to give up smoking for Stoptober, while others try to quit drinking for Sober October. We asked readers to tell us what enabled them to give up a longstanding bad habit, and how their life changed as a result.

Ruth, 53, Nottingham: ‘I read Allen Carr’s The Easy Way to Stop Smoking and gave up cigarettes three days later’

I had recently started a new job and there were two staff rooms: one was large and inviting, bright, light and airy; the other was a cramped, rancid-smelling box room with a large, overflowing basin of stubs and fag butts on a low table in the middle. Yes, the gossip in the box room was juicier, and the camaraderie more cosy, jammed shoulder-to-shoulder as we were in the smog, but it was all tinged with ... well, just what was it? I found myself, not for the first time in 18 years of smoking, questioning my predicament.

A colleague who frequented neither staff room enthused about a book called The Easy Way to Stop Smoking by Allen Carr, and said I should read it. I dismissed the idea. “I don’t do self-help books,” I said, with obstinate pride and lofty disdain. I didn’t like the colleague much, so was not disposed to listen to him. But a week later I noticed the book on sale, and bought it. I went home, made a cup of tea and settled down, with my cigarettes at my side, to read it. What happened was a surprise rewiring of my brain. Myths were exploded. Truths were exposed. A shift in my consciousness changed my life as a smoker and set me free. I stopped smoking for good three days later.

Lisa, 54, Birmingham: ‘I used to binge drink but now I’m about to do a half-marathon’

Every time I went out socially it would involve drinking and late nights, and I would often have a feeling of remorse the morning after because of what I might have said or done. I used to drink either sauvignon blanc or prosecco and quite often shots would follow. Drink is great when you’re in control – but I often wasn’t.

I broke the habit by nursing a drink sometimes, but not drinking it all. It meant people couldn’t refill it and it looked like I was still drinking. I would also buy a much bigger drink, but make it last the whole evening. I now consume less alcohol and save money as a bonus. I am outgoing and sociable anyway, but it took me a long time to realise heavy drinking did nothing to improve my evening. My partner of 11 years doesn’t drink at all, so that makes it easier.

The past three years I have taken up running: I started with 5k races, then 10k and now I’m about to do a half-marathon in three weeks. I go out and have fun but I rarely get drunk and I wake up fresh and energised.

Harry, 23, Beckenham: ‘A small anniversary gift enabled me to give up biting my nails’

I wanted to give up biting my fingernails because of the pain that accompanied biting too much off, how my nails looked and its association with my anxiety.

After starting to work in the mental health sphere, I began making associations between my thoughts and behaviours. I tried going cold turkey with the nail biting but I would always find myself with my finger in my mouth, playing with any extra bit of nail.

My girlfriend suggested a nail file and gave me a metal one as a little anniversary gift. Immediately I liked the fact that it gave me something to distract myself with while also keeping my nails strong. It was a bit embarrassing to begin with, but has proved a solid investment. It has been well over three months now since I stopped biting my fingernails, and my life has changed in ways big and small. I can now peel off a label, and have a crack at tough knots without my teeth getting involved. My confidence has also increased and I feel better about my ability to kick other annoying habits.

Rob, 65, Durham: ‘I made a tape-recording of myself citing all the reasons to stop drinking. I played it once and stopped’

I woke up one day and knew I had hit rock bottom with my drinking. I had had an attack of gastritis a few days before and been told my liver function was not so good. Basically, I was in hell.

In an attempt to give up I made a tape- recording of myself talking to my unconscious, citing all the reasons to stop drinking. I played the tape once and stopped drinking and haven’t had any kind of alcohol since. That was 21 April 2005.

I don’t have hangovers any more or depression. I’ve also managed to save a lot of money. At the same time, giving up was the hardest thing I have ever done. Now that I can’t use alcohol as an escape route, I have to face my anxiety, fears and weaknesses head-on.

Lauren, 27, Leeds: ‘A book by Marie Kondo helped me kick my hoarding habit’

I had brought a boyfriend back to my flat and he accidentally opened the door to my hoarding cupboard and got a shock. He was good-natured about it and laughed it off but I was so embarrassed that I realised if I wanted to really let anybody in emotionally, I’d have to kick the hoarding.

I bought the book The Life-Changing Magic of Tidying Up by Marie Kondo, and made the decision to throw away everything that wasn’t reusable. By the end of this process, I still had a lot of stuff, but only about a third or a quarter of what I had before. I’ve been working on reviewing my possessions a couple of times a year since then, and getting rid of anything that doesn’t work for me.

I feel more emotionally stable now. Although I still suffer from anxiety from time to time, it is actually easier to deal with without all that clutter holding me back.

Donald, 55, France: ‘A diagnosis of tongue cancer led me to grab the nicotine gum and patches’

In 2011, I was diagnosed with tongue cancer, so gave up the cigarettes, cold. I had been a heavy smoker, about a pack a day, starting when I was 13 or 14, so had been smoking for more than 35 years.

I announced my condition to everyone, and told them I had given up smoking, grabbed nicotine gum, puffers and patches and went for it hell for leather. After about three weeks of tension I relaxed, and have not had a moment of missing cigarettes since. When I had given up in the past, the desire was a real problem. I would dream of smoking, and the feeling was so real that I would wake up with the smell in my nostrils.

I noticed no real effects from not smoking. Having said that, this year I was diagnosed with lung cancer and have had surgery to remove a lobe containing it. My surgeon, commenting on my long recovery time despite keyhole surgery, said my lungs were a mess from long-term smoking. But outside of lung function, the benefits are that I no longer smell like an ash heap, I don’t get so many colds, and my sense of smell is better. My taste buds are better too, but that may be recovery from the tongue cancer radiotherapy, which destroyed them. The last thing I would want anyone to experience is having no taste buds; everything tastes like ashes in your mouth and it is so depressing. But when they grow back, they are young again, like a baby’s and so you taste things afresh. The first few days after they came back I couldn’t suck a Polo mint – it was too strong.

Some names have been changed

• This article was amended on 28 September 2017. An earlier version referred to a reader as ‘Luke, 53, Nottingham’. This has been change to ‘Ruth’ as the reader got in touch after publication to say that she would like her real name to be used.