Despite pulling out all the stops — trading junk food for wholesome snacks, making your own meals, and regular kickboxing classes — you still struggle to shed those last few kilograms.

Don't assume that means you can't reach your goal no matter what you do. Experts say that in many cases, the smartest-sounding diet strategies can actually work against you.

Fortunately, if you adjust your approach to these healthy behaviours, you can move the scale in the right direction.

You're loading up on wholegrains

You've rid your pantry of snacks made with white flour, replacing them with heart-healthy wholegrain versions. "But many of these snacks may be high in fat, sugar and sodium — not to mention kilojoules," says dietitian Lisa Sasson.

Make this small change:

People who eat the greatest number of servings of minimally processed whole-grain foods — not snack foods, such as crackers, biscuits and chips — enjoy the biggest weight-control benefits, research shows. Increase your intake of brown and wild rice, oatmeal, quinoa and wholegrain breads and cereals.

"Not only do most of these foods contain fibre, which helps curb your appetite, but they're also low on the glycaemic index (GI)," says Sasson. "The carbs in low-GI foods are absorbed into your bloodstream slowly, allowing you to go longer without feeling hungry."

You allow yourself a cheat day, or two

You've probably learnt from experience that denying yourself all treats when you're dieting can set you up for a binge. Your solution? Being 'good' during the week and allowing yourself to splurge on weekends.

While this may seem like a moderate approach to weight loss, it's still a feast-or-famine mentality that can easily backfire. Dieters who shed a small amount of weight each weekday gained most of it back between Friday night and Monday morning, according to a recent study from the Washington University School of Medicine (US).

"When trying to lose those last few kilos, every kJ counts," says nutritionist Kathy McManus.

"By eating whatever you want for two days straight, it's almost inevitable that you'll undo the hard work you put in during the previous five."

Make this small change:

When it comes to shedding kilograms, consistency is key. One study in the International Journal of Obesity found that people who eat a similar number of kJ over seven days are 50 percent more likely to maintain their weight than those who diet more strictly on weekdays.

That means you'll be more successful if you allow yourself a 650—850kJ treat a few times a week, rather than waiting until Friday night happy hour to splurge.

You make your own meals

There's little dispute that frequently eating out can wreak havoc with a healthy eating plan.

Researchers found that restaurant chefs may serve dishes two to four times larger than the portion size recommended by dietetics associations. So it would seem that by grocery shopping and cooking at home whenever possible, you'd be doing your waistline a favour.

That may be true, but if you're not vigilant, this strategy can easily translate into extra kilograms. Habits such as picking at food while you cook, adding just a bit of extra butter or oil, using a heavy hand with dressings and sauces and nibbling leftovers as you're clearing the table can tack on hundreds of kilojoules to an otherwise healthy meal.

Make this small change:

"Pull out your measuring cups and spoons and use them throughout the entire cooking process," advises Sasson.

"That way the next time you're adding oil to a pan or pouring marinara sauce over your pasta, you'll have a better sense of the amounts you're using."

A food scale can help you weigh items that can't be measured in cups, such as poultry, fish and cheese.

When you're ready to eat, take a small portion of food (use a salad plate rather than a dinner dish), then put the rest of the meal into single-serving storage containers. Popping them directly into the freezer can deter you from polishing off a second dinner soon after finishing your first.

You squeeze in workouts

No matter how tired you are in the morning or after work, you still push through your cardio session. Better to burn a few kilojoules than none at all, right? Not necessarily.

"If you're feeling truly exhausted, it's more beneficial to ditch your workout," says Dr Alejandro Chediak, a sleep disorders specialist. Reprioritising to allow yourself an extra hour of shuteye may be a smarter move than lacing up your trainers.

"When you’re sleep-deprived, your hormone levels change, stimulating cravings for starches and sweets," says Dr Chediak. Your willpower diminishes too. One recent study from the University of Chicago (US) found that people who had just a single night of poor sleep upped their intake of carb-rich snacks the next day by more than 830 kJ.

Another reason you might want to put off your workout: "You may not be able to exercise at the same intensity or for as long when you're tired," says personal trainer Jessica Matthews.

"You're also more likely to compromise your form, increasing your risk for injury."

Make this small change:

Few of us can get eight hours of sleep and have the time for an hour-long workout. Dr Chediak suggests getting at least seven hours of sleep and scheduling workouts earlier in the day, as exercising within four hours of your bedtime may hinder your ability to fall asleep.

You eat slowly, savouring every bite

It might just be the world's most oft-repeated diet advice — eat slowly and you'll consume less. But while this may work well when you're alone, lingering in a group situation seems to have quite the opposite effect.

A review from the Proceedings of the Nutrition Society found that people take in 40 to 70 percent more kilojoules when they're dining with family and friends.

"People tend to eat more when they're in pleasant surroundings, such as at a restaurant or dinner party," says assistant professor of marketing, Collin Payne. "Socialising serves as a distraction, making it hard to monitor what's on your plate."

Make this small change:

When going out with friends, have a dining strategy in place so you don't have to think about kilojoules at the table, says Payne.

"For example, decide whether you'll have a slice of bread or a glass of wine. You might also order an appetiser as your main dish instead of an entrée."

You enlisted a friend to help

Teaming up with a girlfriend seems more fun than trying to eat healthily alone, which is why you talked your best friend into joining that weight-loss programme with you.

Unfortunately, her unenthusiastic attitude can take a toll on your goals, suggests research from the Journal of Consulting and Clinical Psychology.

"Partners observe the other's eating and exercise habits and alter their own behaviour to match," says researcher Prof Becky Marquez. So if your friend finds excuses to skip scheduled workouts or indulges in unhealthy snacks that aren't on your plan, you're likely to follow suit.

People who make the most successful weight-loss partners are those who are committed to losing 10 percent of their body weight and plan to stick with the programme for a set period of time.

"If you have to convince your friend to join you in an eating plan or exercise regime, she probably isn't ready," says Marquez.

Make this small change:

Discuss your eating and exercise goals with your friend, advises Marquez. If you don't share the same level of commitment, don't feel bad about gently ending the partnership. You may be better off on your own or finding someone who can pull her weight.