Here's how we scaled back and made diets work

Our post-festive promise to kick the sugary treats, cut down the fatty foods and actually fit into our summer swimwear may be well-intentioned, but it's a harsh fact that up to 90 per cent of us will fail as the reality of trying to keep up a strict regime kicks in.

According to Weight Watchers, 13 January is the day when most of us will decide to start our New Year diet – right after we've finally managed to polish off the Christmas treats and suddenly discover the motivation to start shedding all those excess pounds.

With the slimming organisation's research revealing that 74 per cent of women expect to put on around half a stone during the festive period, there's plenty to lose.

For those who succeed, there's not only a new wardrobe of smaller clothes to enjoy, but there's also the added benefits of improved health, more confidence and the smugness of knowing they did it while the rest of us succumbed to the biscuit tin.

But why is it that they manage to reach their goals and slim down, while the rest of us simply give up and head to the chip shop?

What can we learn from our most successful slimmers to help us on hit our own target weight?

The Post Office counter assistant and mum to toddler Ellie used to love to snack on high-fat cashew nuts in front of the TV. Now she still loves to snack, but on carrots and celery.

"I'd buy a tin of nuts, sit in front of the TV and eat them all – now I can't bear to think how many calories that would be.

"I still wanted something to snack on so I'd chop up carrots and celery and open a low-fat dip.

"My other tip would be not to be too embarrassed about joining a class and to go regularly."

She loved her "designer" coffees, but with a full-fat latte stuffed with 350 calories, washed down with a sweet treat, the weight piled on.

Now, she's swapped those high-calorie coffee breaks for a slimline alternative.

Alison, who went from 21 stones and a size 28-30 to size ten in two years and is now about to become a Weight Watchers leader, says: "I loved cinnamon swirl pastry, then discovered that one of those with a latte was the equivalent of a meal, so now I have a biscotti instead."

She also swaps after-dinner desserts for another coffee on nights out. "You have something to occupy you."

Alison also ensures she has "me time" to enjoy some indulgent treats. "Every Sunday, I'd eat what would become known as my single 'Sunday Choc'. Everyone knows not to disturb me until after this important ritual!"

Karen, a pharmacy technician, saw her weight soar to 20st 2lbs after a diet of takeaways and nights out as a student. Eating multi-packs of crisps in one sitting didn't help.

"I was obsessed by crisps. But if I swapped the bags of crisps for rice cake Snack-a-Jacks, I got the savoury thing that I craved but without the big calories.

"As the weight came off, I made sure I rewarded myself by buying new clothes in smaller sizes."

The singer from Leith got to the "boot camp" stages of the competition after wowing the judges with her determination to get from 29.5 stones to just 11.

Size ten Lisa says her tip involved her favourite treat, chocolate. "My trick was freezing chocolate," she says. "It is harder to eat and therefore lasts longer, so you can't wolf it all in one go."

She suggests we eat more "chips", but only if they're made from butternut squash.

"Butternut squash is fabulous," she says. "For a long time, no-one really knew what to do with it, you'd see it in the supermarket but didn't buy it.

"But it makes great 'chips'. Chop it up, spray on some light oil – try Frylite – sprinkle on some cajun spices and roast in the oven. They might not crisp up exactly like potato chips, but they are delicious and much healthier."

Her other top tip is obvious but often tricky to stick to: "Don't buy in things you can't resist. If you have it, you'll eat it."

Along with colleague Julie McKay, she has helped hundreds of slimmers hit their weight targets. Their top tips are: "Take control, small steps make a difference, remember you will never fail unless you stop trying. One way to start taking control is to record everything that you eat and drink, be honest with yourself and success will follow."

Like most men, he used to enjoy a pint at the pub and a takeaway – but the calorie-laden evenings out piled on the pounds.

"I didn't want to give up my nights out," says Phil, who works at the Edinburgh Dungeon.

"But a pint of lager has around 250 calories. So now I swap that for a lower calorie spirit – something like vodka or gin has around 70 calories – and top it up with lots of diet cola."

Weight Watchers: www.weightwatchers.co.uk Scottish Slimmers: www.scottishslimmers.com Rosemary Conley: www.rosemaryconley.com

Falling off the weight loss wagon is as easy as pie. Weight Watchers has listed the top five reasons why diets fail and advice on how to beat them.

DIET BUSTER: You can't stop picking at snacks at your desk or in front of the TV.

SOLUTION: Control hunger by including filling foods (such as vegetables, low-fat diary products and lean meats) at meal times to keep you fuller for longer. If you still need to snack go for healthier choices like natural popcorn or vegetables and low-fat humus.

DIET BUSTER: You opt for a takeaway rather than cooking when tired.

SOLUTION: When you do cook make extra and freeze it for instant meals.

DIET BUSTER: One biscuit isn't enough - you just can't stop yourself eating your way through an entire packet.

SOLUTION: When you feel the urge to eat, distract yourself by calling a friend or going for a walk.

DIET BUSTER: You find the pressures of family life means you can't stay on track.

SOLUTION: Opt for a flexible weight-loss plan that fits in around your lifestyle.

DIET BUSTER: You feel a bit down – and eat a whole tub of ice cream.

SOLUTION: Gain emotional support by talking to friends, family, and colleagues around you when you decide to lose weight and look to them for comfort, not the ice cream.