In the battle to lose weight, you might deem calories evil villains that must be stopped. With superhero determination, you may dramatically slash the 'bad guys' until your jeans fit again.

On the one hand, such Superwoman strategies work -- eating less tends to lead to weighing less. But if you blast away too many calories, you're in for trouble. You may shrink down quickly but as soon as you eat more, you'll plump up again – foiled by the dreaded yo-yo effect! 

The fact is: Restrictive diets aren't sustainable for long-term weight-loss success. What's more, you won't have strength to be Superwoman because you need calories for energy.

The solution? Trim calories instead of hacking away at them. By tweaking your diet, you can lose weight without depriving your body or taste buds. Then you're more likely to get slim and stay that way. Here's how.

Eat a little less but eat well. Your lower-calorie diet should be satisfying and balanced, offering lean protein, complex carbohydrates, healthy fats and veggies or fruit at every meal. 

It may sound like a lot of work, but it's truly simple. The proof is in the following meals recommended by Ma, they're fast, tasty and all under 500 calories.

To make: Heat a bit of olive or canola oil in a wok or large frying pan, then cook chopped garlic and onions, strips of beef, chicken breast or tofu. Add at least three different types of vegetables, such as broccoli, carrots, red pepper, snow peas and mushrooms. Season with a splash of low-sodium soy sauce and grated ginger. Cook until veggies are tender and protein is cooked through. Serve over brown rice. 

Portion size:  Have 1/2 cup cooked brown rice and the equivalent of 4 ounces of protein (about the size of your palm) and a couple of cups of vegetables.

Nutrition tip: "The more veggies you put in, the better, as they're fibrous, nutrient-dense and low-cal," says Ma. 

To make: Bake or boil skinless chicken or turkey thighs. Slice up the cooked meat, then put it onto a whole-wheat tortilla wrap. Smooth on a bit of low-calorie mayonnaise or mustard and pile on vegetables such as sprouts, chopped lettuce, sliced bell peppers and tomatoes. Roll up the wrap, and enjoy.

Portion size: Include about 4 oz of poultry (the size of your palm), 1 tsp of mayonnaise and all the vegetables you want! 

Nutrition tip: For sandwiches, whole grain wraps are preferable to bagels. That's because they're thinner and lower in calories, with about 170 per wrap versus about 290 in a single bagel.