Over the past few years, the hottest trend in the food industry has been the onslaught of healthy food labeling, like "healthy fats, fat-free, low-fat," etc. They are everywhere it seems. Unfortunately, many of these foods are packed with fat, sugar and empty calories. Below are some of the most devious diet foods today. Don't fall into the hidden traps.

Olive oil:Sure it's heart-healthy, monounsaturated oil, but it's also rich in calories and fat. Oil is oil, whether its olive oil, or some other kind of oil, it still has 120 calories and 14 grams of fat per tablespoon. You're better off using a pat of butter (for bread) than dipping it in olive oil because the bread sops up the oil like a sponge. So a little bit of butter is better than a lot of olive oil.

Tuna fish:Think that tuna sandwich is a light lunch? Think again. The average overstuffed tuna sandwich served in a restaurant contains 700 calories and 43 grams of fat. The culprit? The mayo. Tuna fish has just 35 calories per ounce and it's full of omega-3s, but mayonnaise has 100 calories per tablespoon. You're better off having a turkey or even a roast beef sandwich. Even chicken salad is better than tuna salad, because tuna is so fine there's a lot more surface area for the mayonnaise to fill. Switch to fat-free mayo or mustard to save on more than half the calories and fat.

Granola:Granola may sound like the healthiest term, but beware - it's often loaded with tons of calories and fat. That's because granola cereals often contain oils, including coconut oil - which is high in saturated fat, sugar, nuts and other high-calorie foods. Something like Fiber One has 60 calories per half cup and 14 grams of fiber versus a half cup of granola, which was 240 calories, 5 to 10 grams of fat and just 3 grams of fiber. Increasing your fiber intake is the key to feeling full and satiated.

Sushi:Japanese food is inherently healthy, but when you Americanize it and start adding things like cream cheese and avocado, that's when you run into problems. For example, a spicy tuna roll has 290 calories and 11 grams of fat, and a tempura roll has 320 calories and 17 grams of fat. Instead opt for lean tuna sashimi, which has about 35 calories and 1 gram of fat per ounce. You're better off going with sashimi, miso soup (36 calories) and a salad (35 calories with a tablespoon of non-creamy ginger dressing).

Frozen diet meals:Sure Lean Cuisine and Weight Watchers frozen entrees are fairly low in calories and convenient, but they're also highly processed and high in sodium. I understand the convenience factor, but most of these meals have more than 600 milligrams of sodium, the portions are really small and they're not very satisfying. So you eat one for dinner and then by 9:00 p.m. you're hungry again. You're better off eating a slice of whole-wheat bread with some light sauce and light mozzarella, or an egg white omelet with some vegetables.

Protein bars:Another convenient food - but not very nutritious - protein bars are basically glorified candy bars. They're also often high in calories, fat and do little to satisfy a person's hunger. A better choice is grabbing a piece of fresh fruit and a piece of string cheese or some dark chocolate and an ounce of nuts. These combinations of fiber and protein will help fill you up without filling you out.

Pretzels:They're low in fat and low on nutrition. They're basically empty calories, inherently, pretzels themselves are not unhealthy, but they're basically all sugar so they'll make you hungrier and you'll gain weight as a result of over-eating. Instead, opt for whole-grain crackers to satisfy the crunch with a boost of fiber and spread some low-fat peanut butter or cheese on it. If it's just the snack factor you're looking for, pop some popcorn in your microwave for a low-cal, healthy snack of fiber and protein.

Fat-free, sugar-free muffins:Regardless of whether a muffin is fat-free or sugar-free, they still usually have around 600 calories. It's nothing but cake in disguise, especially these double chocolate chip-type muffins. But even bran muffins are very dense and very high in calories. The same thing goes for scones. People think that because they're not sweet, they're healthy.

Tanya Zuckerbrot, MS, RD is a nutritionist and founder of

www.Skinnyandthecity.com

. She is also the creator of The F-Factor DietaC/, an innovative nutritional program she has used for more than ten years to provide hundreds of her clients with all the tools they need to achieve easy weight loss and maintenance, improved health and well-being. For more information log onto

www.FFactorDiet.com

.

Tanya Zuckerbrot MS, RD, is a Registered Dietitian in New York City and the author of two bestselling diet books: The F-Factor Diet and The Miracle Carb Diet: Make Calories and Fat Disappear – with Fiber.

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