A study in the European Journal of Social Psychology found it takes an average of 66 days to make a new behaviour automatic. But it varies according to the behaviour – drinking a daily glass of water became automatic very quickly, doing 50 sit-ups before breakfast took much longer.

A few years ago, I decided I wanted to start flossing. My dentist had always encouraged it, I’d read plenty about its benefits for gum health and yet, for some reason, I’d never been able to stick at it.

The first few times I slid the twine between my teeth were unpleasant. My gums bled so badly I looked like a vampire fresh from a feed. This sucks, I thought, and not in a way that would please a pasty immortal being. But I was determined. I knew, like eating fibrous greens and knocking out burpees, that flossing was good for me.

Gradually, the daily blood bath began to dissipate. At the same time, I started to get a perverse pleasure from dislodging particularly stubborn scraps of food from behind deeply set molars. And, afterwards, I enjoyed feeling like my gums were getting healthier.

Researchers at Duke University found up to 45 per cent of daily activities stem from habitual behaviour

Fifty metres of floss later and flossing had become part of my daily dental routine. One I no longer dreaded but almost relished. And perhaps most importantly of all, one I no longer really thought about. It was as habitual as, well, brushing my teeth.

Researchers at Duke University found up to 45 per cent of daily activities stem from habitual behaviour. If you think about your day so far, from shaving, to your morning coffee, to maybe even reading this magazine on the dunny, you’ll find that much of it was the result of unthinking routine.

There are good reasons for this. Habits promote efficiency, eliminating pesky decision-making and freeing us to devote precious mental energy to more important tasks, like inventing fire, mastering agriculture and landing a red leather ball on a good length. It’s why habits, both good and bad, can come to define our lives. We are what we do over and over again. It’s also why it’s so important for us to pursue positive habits.

The trouble for many of us is that, not only do our brains seek comfort in ritual and routine, they also seek reward. That’s a problem because we live in an environment specifically designed to satisfy our desires.

A perfect storm of kilojoule-rich foods, around-the-clock convenience, marketing, advertising and the accelerating pace of technological development are all conspiring to entrench bad habits. How often have you dialled a pizza because you couldn’t be bothered cooking? Been sucked in by an ad for a new flavour of Magnum ice-cream, or spent a commute keeping track of your likes on Facebook while the latest Tim Winton novel lies unread in your bag?

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But what if there was a way to increase your chances of locking in life-shaping habits so that you could tilt the balance back in your favour? And what if, rather than being a slave to your desires, you could be master of them? It’s a tantalising prospect, because as researchers gain a better understanding of the way our brains work, the real secrets of sustained drive and motivation, and the true levers of transformation may be within your grasp.

Did you clean your teeth this morning? Silly question, right?

Not if you’d lived in the Twenties. As Charles Duhigg writes in The Power of Habit, back then in the US, tooth-brushing was regarded as flossing is today, with only around seven per cent of the population practising it regularly.

The reason tooth-brushing became popular is due to an advertising executive named Claude Hopkins. He successfully marketed a brand of toothpaste called Pepsodent by taking advantage of the way our brains work, specifically how they respond to cues and rewards.

A behaviour only truly locks in once your brain starts anticipating the reward.

The problem for toothpaste manufacturers previously was that not only was there no cue to trigger the practice of brushing, there was no reward afterwards. Hopkins addressed this problem, writes Duhigg, by focusing on the furry feeling on your teeth caused by the buildup of plaque. That was the cue. The reward was a beautiful smile.

But that still wasn’t enough to create a strong habit. A behaviour only truly locks in once your brain starts anticipating the reward.

“When you have a behaviour that leads to a dopamine response frequently, you come to experience the reward state before you’ve actually engaged in the activity,” says Dr David Neal, a leading behavioural scientist and director of market research firm Empirica Research. In short, you create a craving for it.

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In the case of toothpaste, explains Duhigg, it emerged that the tingling sensation caused by ingredients such as citric acid and mint oil, which was unique to Pepsodent at the time, was a powerful neurological carrot.

The process of cue, routine and reward propelled by cravings is known as the habit loop and is the behavioural blueprint for almost all our actions. It certainly worked with toothpaste. Within a decade of Hopkins’ marketing campaign, Pepsodent was among the most popular products in the world.

The principles of the habit loop can be used to make many desirable behaviours automatic. If you want to start lifting weights, for example, focus on the endorphin hit and sense of accomplishment you’ll feel afterwards. Do it enough and you’ll start to crave those feelings.

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But the habit loop also highlights a broader problem in terms of health and fitness – some behaviours target the reward centres of our brain more directly than others.

“Things like smoking, drinking and junk food are extremely habit producing because they tap directly into the reward system, giving you an immediate hit,” says Dr Martin Hagger, a professor of psychology at Curtin University. With something like exercise, adds Hagger, the effects are more long term and less direct.

This reality underscores a rather inconvenient truth in habit formation: it’s driven by human nature. If a habit is easy and rewards us quickly, we adopt it swiftly. If it requires work, our brains start to protest. The problem in modern society is that the environment – the one we created – is geared towards convenience and gratification. It encourages and enforces bad habits.

What’s the solution? “Environmental re-engineering,” says Neal. “Successfully changing our habits requires us to alter the environment in ways that cue healthy behaviours and disrupt unhealthy ones.”

That means increasing the “behavioural friction” surrounding bad habits, says Neals, like putting your phone in another room when you go to bed so you’re not tempted to stare at its bright screen when you wake up in the night. And decreasing friction around good habits, like packing your gym gear the night before.

What you’re really doing here is decreasing your reliance on willpower. It’s slightly counter-intuitive, because it means in order to be master of your domain, you have to acknowledge your weaknesses.

82-year-old Tom Hafey does 350 push-ups every morning.

Every morning at 5.20am Tom Hafey’s alarm clock goes off.

The 82-year-old former AFL player and coach rises and, as he has done almost every day for 50 years, he heads out the door for a five-kilometre run around the bay in Melbourne’s St Kilda.

When he returns, he does around 10 minutes of stretching. He then does 350 push-ups before going for a dip in the ocean. Finally, he returns home and does 700 abdominal exercises.

Hafey is a popular after-dinner speaker, and sometimes doesn’t get back from engagements until 1.30am, yet when that alarm goes off, he still leaps out of bed.

“If you don’t do it you’re a wimp,” says Hafey, whose leathery old body still ripples in all the right places. “It’s about pride in yourself. I’m always hearing people say they’re gonna do something. Talk is worth nothing, it’s action that counts.”

“Your habits are the pillars that hold up your willpower, developing good habits takes the pressure off willpower.”

Hafey is a no-nonsense type of guy. You can imagine him flogging himself and his players back in his coaching days, not brooking argument or excuse. You’d assume the man must be blessed with enormous reserves of willpower. You’d be right. Hafey’s pride in himself and his innate work ethic were both crucial in giving him the motivation to begin the routine in the first place.

“Habits are the residue of past goal pursuit,” confirms Neal. But it’s been a long time since Hafey actually had to rely on willpower to drag himself out of bed.

The truth is, Tom’s routine is ingrained. There is no decision to be made each morning, no deliberation necessary. It is automatic.

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“Your habits are the pillars that hold up your willpower,” says Matt O’Neill, a nutritionist and founder of weight-loss program Smartshape.com.au. “Developing good habits takes the pressure off willpower.”

That becomes particularly important during times when your willpower is low, such as when you’re tired or stressed. In such times you’d expect good habits to go out the window. But in a remarkable study Neal conducted on college students during exam periods, he found they defaulted to existing habits, good or bad, when under pressure. Those who regularly ate a healthy breakfast were more likely to stick to that routine. But those who usually ate junk food continued that habit as their stress increased.

“We found that if behaviour is a really strong habit, it’s actually more likely to be performed when people lack willpower,” says Neal. “You act more habitually across the board.”

That’s bad news if you have a lot of negative habits. It means stress compounds and further entrenches toxic behavioural patterns that can precipitate a downward spiral. But good habits are not only protective, they actually get amplified when you lack willpower. It’s kind of like a mental insurance policy, says Neal. Only you don’t just come out of a stress cyclone with a house similar to the one you had before. Because positive habits are cumulative, you actually emerge with a better one.

Most nights during Craig Emery’s two-and-a-half years as general counsel for Telstra he would regularly wake at 2am

Craig Emery is a man who needs his sleep.

As general counsel for Telstra’s retail division, the 35-year-old father of two has one of the most high-pressure in-house legal jobs in the country. His 12-hour days involve negotiating contracts, ensuring compliance with fair-trading and consumer laws, and managing disputes and litigation for a company that pulls in over $25 billion in annual revenue and employs more than 60,000 people.

“There’s a bit on,” Emery deadpans as we chat in a meeting room in Telstra’s head office in Sydney.

Not surprisingly, it’s the kind of role that can keep you awake at night. Most nights during Emery’s two-and-a-half years in the job he would regularly wake at 2am, his mind springing into action, formulating strategies to deal with problems at work.

“I’d tend to play out what-if scenarios,” he says. “If I gave this advice what would happen; if I gave it this way, what would happen?”

“I’d get to Friday night and the only thing I could think about was having a beer.”

He’d lie awake until 4am then get up and go to work. Not surprisingly, this affected his mood, his productivity and how he engaged with his wife and two young children. “I was just too tired to be useful,” he says.

Emery’s coping mechanism was to attack his work even harder. As a result, his work week became an ordeal to get through. “I’d get to Friday night and the only thing I could think about was having a beer.”

The problem got progressively worse – until early last year when Emery took a guided meditation class that gave him a grounding in the mechanics of diaphragmatic breathing.

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The session was useful, but Emery remained unconvinced. “I kind of thought ‘That’s interesting, I wonder if I’ll ever do that again’.” Fortunately, he got an opportunity the very next day when a meeting with a high-level client saw him gripped with anxiety.

He decided to give mindfulness a chance to prove itself. Ten minutes before the meeting, he went into a quiet room, sat in a chair with his eyes closed and imagined his diaphragm was a balloon, slowly inflating in and out. “It worked wonders,” he says, citing improved sleep patterns, increased alertness during meetings and far better mood.

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That was in February last year. From there, he began using diaphragmatic breathing before all big meetings and whenever he woke in the night. Where so many people fail to adopt meditation as a habit, Emery succeeded for several reasons.

First, his work-related stress represented a strong cue, both in its intensity and its regularity. A study in the European Journal of Social Psychology found that, on average, it takes 66 days to make a new activity a habit. “I have significant opportunity to practise,” admits Emery. “It’s not like I’m in a stressful situation once a week or once a month; it’s almost daily.”

But habit formation is more than a simple matter of repetition. Also vital is the context in which you do it. “If you repeat a behaviour but you do it in different environments with different people, it may never become a habit,” says Neal. That’s because those little differences are enough for your brain to have to switch off the autopilot and actually have to work to establish the best course of action.

But the more “context stable” the environment, explains Neal, the easier it is for the brain to fall back on routine. “You want the same environment, the same time of day, in exactly the same way,” he says. For Emery that was easy. He practises mindfulness in bed or his office.

But context is a double-edged sword. It’s fine when, like Emery, you’re able to use cues and context to your advantage. More often than not, though, society, or “the house” has loaded the dice against you. And that’s when things get tricky.

Civil engineer Michael Smith was particularly vulnerable to cravings when bored or stressed, gorging on kilo bags of Snakes during his uni exam

Remember your last trip to the cinema? If you managed to get out of there without forking out for a giant box of popcorn, cola and a choc-top, you’ve done pretty well.

Perhaps more than any other setting, the cinema, with its overt external cues for consumption, personifies what researchers refer to as an “obesogenic” environment. Just how powerful these cues can be was demonstrated in a study Neal published in the 2011 issue of the Personality and Social Psychology Bulletin, in which subjects ate popcorn in a movie theatre, whether or not they liked it or were hungry. They only stopped when asked to switch to their non-dominant hand, a request that interrupted the pattern and context of the habit.

The fact is, without contextual cues and environmental reinforcements many bad habits would wither – most of us don’t eat much popcorn outside of cinemas. In terms of temptations, though, one thing we can’t escape is sugar.

This was the problem for Michael Smith, a 23-year-old civil engineer from Shellharbour on the NSW south coast. Five years ago, Smith was a slave to his sweet tooth. If he saw something that looked appetising he didn’t think twice about scoffing it down. Smith was particularly vulnerable to cravings when bored or stressed, gorging on kilo bags of Snakes during his uni exams.

“The cue might be the 3pm slump, but instead of eating a chocolate bar you go for a 15-minute walk and you come back feeling energised.”

After jumping on the scales in a surf shop and watching the needle rocket to 120kg, Smith decided to take action, cutting out added sugar and processed foods.

It wasn’t easy. Sometimes his mum would bake a tray of biscuits and sit them on the benchtop to cool, driving him to distraction. “You’d just crave it so much,” Smith says of sugar. “I was getting head spins it was that bad.” Plenty of times, he fell off the wagon and had a “massive binge session” when out with mates.

But over the course of a year, Smith was gradually able to ignore his cravings. How? He altered his habit loop.

“Often the key to behaviour change is to keep the cue and the reward but change the routine,” says Andrew May, director of The Performance Clinic. “The cue might be the 3pm slump, but instead of eating a chocolate bar you go for a 15-minute walk and you come back feeling energised.”

In Smith’s case, whenever he felt the craving for something sweet, he drank water. Lots of it. Up to a staggering 15 litres a day. If that didn’t work, he ate a piece of fruit, allowing himself up to three pieces a day but gradually scaling back to one. Or he went for a jog. “I found if you do cardio, the sugar cravings go away,” he says.

Again, Smith saw significant reward, which encouraged him to keep going. He dropped 40kg in 15 months. Importantly, the sugar cravings subsided to the point that now not even his mum’s biscuits pose a threat. “I wouldn’t even touch them,” he says. “The thought of eating sweet stuff makes me feel sick.”

Smith has replaced a bad habit with one that’s not only positive, but actually drives other constructive behaviours. Researchers call this a keystone habit. “That’s a major habit that can draw in a lot of other habits as well,” says May. “It’s a big lever.” If you exercise, for example, you’re more likely to eat cleaner, manage your time better and sleep more soundly.

The cumulative results can be nothing short of life changing. Don’t believe it? Just ask Smith. He regularly has conversations with people he went to school with who recoil in surprise when he mentions someone they know. The reason? They thought they were talking to a stranger.