New Year's Resolutions. Who'd make 'em, eh? Those promises of restriction, denial and February failure, all couched in the optimistic terms of self-improvement and future glory.

Despite consistently failing to achieve my own resolutions, I at least never fail in setting them - and I'm pretty sure that neither do you. One of the most popular resolutions is to overhaul the food we put in our mouths and lose weight.

However, dieting is notoriously tricky. Many people fail to lose any weight at all and those who do often gain it all back at a later date. These cycles of weight loss and weight gain can then lead to physiological changes in the body that make future weight loss even harder. Ouch.

So diets don't work and instead we need to work on creating healthier eating habits. When trying to do so, our greatest enemies are old habits and cravings. Whilst our long-term goals are regulated by conscious brain processes, habits and cravings are largely driven by automatic brain processes which we have much less control over. When we are confronted by a food "cue" (anything that we associate with eating - be it our kitchen, sitting on the sofa in front of the telly, the golden arches of the McDonald's logo, a smell, an image etc...), it automatically triggers food cravings. If we're not consciously paying attention or if we've run out of willpower for the day, our automatic habitual system will take over and before we know it, we'll have scoffed all the biscuits.

This then creates a vicious cycle - by following our cravings, we reinforce the food cue - eating association, meaning that over time, our cravings in response to that cue will get stronger. Even worse, when we overeat typical Western diet foods (those high in fat and sugar), it can lead to small cognitive impairments that make resisting those foods even harder. In short, it's not just our waists on the line when it comes to January's healthy eating goals.

Most healthy eating interventions for overweight and obese people fail simply because they do not take these automatic processes (and their devilish hold on our behaviour) into account. Whilst it's taking a long time for research to translate into practice, I've done the slogging through academic journals so you don't have to. Here are my top tips for manipulating your unconscious brain in your favour:

1. Pay attention to what you eat. If you're distracted whilst eating, not only will your unconscious brain be able to take over and guide your eating, you'll also lose track of how much you've eaten. Whilst we may think our portion sizes are guided by hunger, research suggests that if you don't remember how much you've eaten, you're more likely to eat more later on. Amnesiacs often show hyperphagia (overeating) and this is thought to occur because they don't remember what they've already eaten. Activities like watching TV and using computers have been shown to increase the amount we eat at a later point - so put the screens away!

2. If you really must watch TV whilst eating, skip the ads. As well as distracting us, screen time is also more likely to lead to food cue exposure in the form of adverts. Research has shown time and time again that adverts showing images of food (or even just food brands and logos) can increase the amount we eat and the effect is particularly strong for children. And adverts don't just push us towards the featured product - it makes us eat more of any food we have to hand.

3. Set achievable goals. Our ultimate aim might be to lose 20lb and get back to the weight we were five years ago - but that's going to take a long time. Such distant goals can lead us to lose motivation when we don't see immediate results. Instead, it's better to create more immediate goals that are a series of small steps towards an ultimate end goal. Perhaps you might set a goal to always take the stairs - once you've gotten into that habit, you can set another goal of eating a healthier breakfast and so on and so on...

4. And choose them for the right reasons. Another thing that causes us to lose motivation is the feeling that a goal is extrinsic to us, rather than intrinsic. What this means is that we feel pressured to do something by outside forces rather than choosing something for ourselves. Weight loss for appearance is often ultimately experienced as an extrinsic goal - we might convince ourselves that we want to lose weight for ourselves but later on we might start feeling that our weight loss goal actually comes from a societal pressure to look a certain way. Health goals can end up the same way too if we feel that health professionals have imposed it on us (in the case of those told to lose weight by their doctors). Wellbeing goals tend to be better for us in this respect - by focusing on the effects a healthy diet has on our day-to-day wellbeing and energy levels, we can start appreciating food as something to lift our mood and make us feel better - which is a goal that can only come from us. These effects are also more immediate so we feel a greater motivation to pursue further lifestyle change.

5. Have a "hot state" contingency plan. We often make resolutions and goals in a "cold" state - when we're not feeling the temptation of our favourite foods. But as soon as we catch the smell of pizza and our cravings leap into action, we find ourselves in a "hot" state that quickly kisses all our good intentions goodbye. Implementation intentions (or "if-then" plans) are a way of recognising these situations in advance and coming up with contingency plans. For example, as I write this I'm not hungry and so am quite happy leaving the nearby box of After Eights on the table. In this cold state, I can quite easily contemplate the idea of giving up snacking on chocolate as a resolution. But later this evening, I know I will be tempted to gorge on the entire box as soon as I see them. By setting myself the implementation intention of "if I have a craving for After Eights, then I will eat two maximum and put the box away", I've created a plan in advance for tackling my "hot state" future self. Believe it or not, this works.

6. Confront your eating triggers. If you know you can't resist dark chocolate digestives (guilty), you might think that the best strategy is to stop buying them and stay away from the biscuit aisle. But this kind of avoidance is counterproductive in the long run. Despite our best efforts, we can't stay away from biscuits forever. In order to truly combat our bad habits, we need to confront them head on and learn new responses to the triggers. Our brains are like probability calculating machines - repeated biscuits = eating incidences means that when we see the biscuits again, our automatic brain kicks in and tells us to eat, regardless of our dieting goals. Keeping away from the biscuits isn't going to teach our automatic brains any differently so the next time we're offered some at our friend's house, those old biscuit = eating associations will come right back into action. Instead, we need to teach our brains new associations through a process called extinction. This is commonly thought of as "unlearning" the biscuits = eating association but it actually involves creating a new biscuits = no(t necessarily) eating association instead. Unfortunately, this means exposing yourself to the trigger and trying your absolute hardest not to give into it. But over time, our calculating little brains will learn that these triggers do not have to mean overeating and so it will slowly become easier to resist.

7. Don't give up! Well, duh. But one of the biggest problems dieters can face is what to do when an inevitable lapse occurs. Changing habits is hard, especially when those pesky reward centres keep lighting up every time you walk past a takeaway. We all fail at maintaining self-control and motivation and that's ok - one binge isn't going to undo all the good work you've done so far. It's how we respond to these lapses that's important. Some people give up as soon as they've lapsed, taking it as evidence for their lack of control over their eating. However, successful dieters put the lapse behind them and continue in their efforts. After all, it's the long-term behaviour change that matters!

I hope you've found this interesting and perhaps even useful! I'm absolutely obsessed with the psychology of eating behaviour so if you fancy a chat about it, drop me a comment or a tweet and I will talk about it for hours with you.

Happy New Years (resolutions)!