If you've lost weight recently, you're no doubt giving yourself a pat on the back. But for your achievement to really count, you have to keep the weight off.
Trouble is, once you've lost weight it's easy to be lulled into a false sense of security. You might think that now you've reached your target weight, you can go back to eating what you want, when you want.
But it's not that easy. If you want to maintain your weight, you need to adopt a lifelong change to your habits.
Psychologist Dr Mike Green from Aston University, who specialises in the psychology of eating, says that changing your eating habits to allow for long-term weight loss means a 'massive' shift in behaviour over a long period of time.
He says that often people who have had a chaotic approach to eating can struggle to lose weight, or keep weight off.
"It's important to regulate your eating patterns. This certainly can't happen by a quick fix approach," says Dr Green.
"You're trying to change attitudes to food that you've built up across a lifetime, including the idea that to lose weight, you need to suppress hunger.
"In fact, research has shown that the reason overweight people eat often has little to do with biological hunger. More often it depends on mood and habit, which means that 'comfort eating' can be sparked by stress, boredom or a desire for a reward."
"If dieters fail to deal with this, as soon as they stop dieting, the weight will go back on."
Lyndel Costain, nutritionist and spokeswoman for the British Dietetic Association, says, "Some people find losing weight harder than others. Genetic influences and learnt eating and exercise habits both play a part. But, in every case, it's crucial to avoid fad diets that promise the earth but are impossible to stick to across a lifetime.
"People who have struggled with their weight are more prone to the dangers of 'all or nothing' thinking. This means that if they eat a 'bad' food, or miss the gym a few times, they start to tell themselves that they've failed, and may as well give up. Changing this thinking is the key to success.
"If you follow a rigid weight-loss programme, the risk of 'all or nothing thinking' is greatly increased. That's why fad diets usually fail."
"When the diet is broken, the dieter feels like a failure and gives up. Really it was the fad diet that was the failure."
While research shows that people may lose weight using a variety of approaches, says Costain, there are common factors that lead to long-term weight loss. And they are all about achieving a healthy diet and active lifestyle in the long term, and not just short-term calorie counting.
"Most people who want to lose weight know what they need to do," says Lyndel. "But more often than not something stops them from maintaining healthier habits.
"When a diet comes along that makes tempting promises, it's easy to jump on board. But always ask yourself: will your chosen approach help you recognise and change the behaviour that has stopped you losing weight, and keeping it off, in the past?"
Group support is an important part of many effective long-term weight-loss programmes. Good slimming organisations take a long-term approach to weight loss, which means that even once you've lost weight, they continue to provide support through group meetings to help you keep it off. The days of encouraging people to lose as much weight as possible, as quickly as possible, are long gone.
Weight-loss expert Jenny Caven says members of her slimming organisation are encouraged to find the motivation, confidence and support they need in order to make healthy and highly effective lifestyle changes for life. Members attend weekly meetings, where a group leader and fellow slimmers can provide support.
Don't forget that at reputable slimming groups, the leader has successfully lost and kept off weight with the particular organisation.
Nicola Wraight, weight-loss expert with another slimming organisation, adds, "We encourage small and achievable changes to physical activity levels, which can then be built upon to create a regular exercise regime: whether that's walking a bit further each week, taking fitness classes or going to the gym. An exercise regime is much more likely to last if it's something you enjoy."
Nutritionist Lyndel Costain says a few key factors are crucial for long-term weight-loss success: