We all know the key to losing weight and keeping it off is watching calories. To achieve that goal, Leslie Beck recommends eating 400 calorie meals each day, plus a mid-day snack. This simple modification will boost your energy, rev up your metabolism and keep you feeling satisfied even during the holiday season.

Leslie, what makes 400 calories the magic number?

If you want to lose weight your total calorie intake will depend on your current weight, your gender and your activity level. So it does vary. But most women can lose excess weight and meet nutrient requirements by eating 1600 calories per day. That translates into three 400 calorie meals, plus one or two mid-day snacks.

Remember, 400 calories worth of food will keep you feeling energized and satisfied longer. You also won't feel hungry an hour or two after eating. That's the key to sticking to a healthy eating plan.

Okay, show us your 400 calorie meals. Let's start with breakfast.

Breakfast Option 1: Peanut butter and banana sandwich with a side of blueberries

Peanut butter (2 Tbsp) and banana (1/2) sandwich on a whole wheat English muffin with 1/2 cup blueberries on the side. Total: 412 calories and 9.5 grams of fibre.

The heart-healthy fat and fibre in this breakfast keeps you feeling satisfied until lunch. It's also a good source of potassium and antioxidants from the fruit. It certainly beats a greasy breakfast sandwich at 500 to 550 calories and as much as 1000 milligrams of sodium!

Breakfast Option 2: One whole grain waffle topped with vanilla Greek yogurt, strawberries and walnuts

This is a fast breakfast that is so good. Here one whole grain toaster waffle is topped it with 1/2 cup low-fat vanilla Greek yogurt, 3/4 cup of sliced strawberries and e tablespoons of chopped walnuts. Total: 388 calories and 10 grams of fibre.

In this breakfast protein and heart-healthy fat slow digestion, making it last longer until lunch. Thanks to the strawberries, it's also an excellent source of vitamin C. In fact, this breakfast supplies 73 grams of vitamin C -- a full day's worth for women.

Let's move on to 400 calorie lunches.

Lunch Option 1: Curried Chicken Pita with yogurt and pineapple for dessert

This is actually my recipe for a curried chicken pita sandwich. I've mixed 3 ounces of chopped chicken breast with 1 tablespoon of plain, non-fat yogurt and 1 tablespoon of light mayonnaise, a little chopped apple, a few sliced almonds and chopped fresh cilantro. Dessert consists of 3/4 cup of plain non-fat yogurt mixed with 1/2 cup of crushed pineapple. Total: 410 calories

Lunch Option 2: Low-fat frozen entrée, glass of vanilla soy milk and clementines for dessert

Portion control is a good thing for people following a diet, but many frozen meals are too low in calories and can leave you feeling hungry and craving sweets in the afternoon. If you want this lunch to provide 400 calories, you need to supplement it. Here, I have added 1 cup of light vanilla soy milk and two clementines. Total: 390 calories

Now, show us a dinner. How much food can we eat for 400 calories?

Dinner Option 1: Chili con carne with a corn tortilla and green salad

This dinner is filling thanks to its high fibre content. For 400 calories you get 1 cup of chili con carne made with beans and lean ground beef or ground turkey. The chili is topped with 1 tablespoon of grated cheddar cheese and paired with 1 corn tortilla (which have half the calories of wheat tortillas) and 1 cup of salad greens sprinkled with 1 tablespoon of Italian dressing. Total: 390 calories

Dinner Option 2: Peanut Chicken Stir-Fry with Red peppers and Broccoli over Brown Rice

This is an easy, satisfying dinner to make. You have stir-fried chicken, red pepper strips and broccoli florets in non-stick cooking spray. At the end of cooking, I have added 2 tablespoons of a light peanut sauce. If you can't find light, use 1 tablespoon of regular diluted with 1 tablespoon of water. Then, serve this over 3/4 cup of steamed brown rice. Total: 415 calories

If you want to build your own 400 calorie meal, what does 100 calories worth of food look like?

  • Lean meat, chicken, 2 ounces
  • Fish, tuna, 3 ounces (1 mini can)
  • Egg, 1 large
  • Cottage cheese, 1 per cent, 1/2 cup
  • Chickpeas, cooked, 1/3 cup
  • Milk, skim or 1 per cent, 1 cup
  • Oatmeal, cooked, 3/4 cup
  • Pasta, cooked, 1/2 cup
  • Popcorn, air popped, 3 cups
  • Whole grain bread, 1 slice
  • Apple, 1 medium
  • Banana, 1 medium
  • Blueberries, 1 cup
  • Raisins, 1/4 cup
  • Orange, 1 large
  • Almonds, 14 whole
  • Avocado, 1/4
  • Cashew, 11
  • Peanut butter, 1 Tbsp.