1. Eating at night will pile on the pounds.
"It's the total calories you consume over a 24-hour period -- and more often, over a week -- that is what causes you to gain weight, and when you eat those calories doesn't matter," says New York University senior clinical nutritionist Samantha Heller, RD.
That said, because you may be more tired at night, your resolve may be lower, Heller says. So you may tend to eat larger portions, or more high-calorie foods, than you would during the day. But as long as you keep an eye on calories and portion size, feel free to set your hunger alarm to the time that suits your lifestyle.
2. It's best to eat at the same times every day.
"Eat when you're hungry, not when the clock says it's time to eat," says Somer. While it can help to keep some consistency to mealtimes, Somers says that forcing yourself to eat when you're not hungry -- or forcing yourself to wait when you are -- only makes it harder to stick to your diet. If you must eat at a certain time - say, during a designated lunch hour at your workplace -- cut yourself some slack the rest of the day and eat only when your stomach says it's time.
3. Dieting with a buddy always makes weight loss easier.
No one doubts that companionship and common goals can pay off for dieters. But Aronowitz notes that there are some instances in which the buddy system may work against you and your buddy"If one buddy fails and the other doesn't, it clearly upsets the balance, and could cause tension and embarrassment," she says. Ultimately, Aronowitz says, weight loss is a personal journey. If you find it's easier with a friend, remember to compete only against yourself -- not each other.
4. Dietary fat keeps you feeling full longer, so you'll eat less.
This was a well-accepted food rule for many years. But Somers says new research has challenged this logic. It has shown that while fat does take longer to digest, "it's actually the least satiating of any food group -- so no, it will not help you control you appetite," Somers says. The foods likely to stave off hunger the longest are protein foods, followed by carbohydrates, then fats, she says.
5. When you blow your diet, you might as well wait until the next day to get back on track.
"Every meal matters, so if you ate that big old piece of birthday cake at lunch, get right back on track with your next meal," she says. "You don't have to have a full day of healthy eating in order for it to count."
6. Refusing food at a party or when visiting is rude.
"If you had diabetes, or a severe food allergy to something, you wouldn't think twice about turning down a food you weren't sure of -- and you should feel that same sense of priority in turning down a food that you know will blow your diet," says Heller.
7. Skipping a meal every now and then will help you lose.
"Skipping a meal means you will be so hungry at the next meal that you are likely to overeat," says Somer. Not only that, skipping meals can actually help lead to a slowdown of your metabolism, meaning you'll burn fewer calories, says Aronowitz.
8. Bread is fattening, nuts are fattening, pasta is fattening.
"It's not what you eat that contributes to weight gain," says Heller. "It's how much you eat that matters most."
Whole-wheat bread, for example, is a great source of nutrients, and it won't make you gain weight more than any other food with the same number of calories.
9. All calories are equal.
While it's true that 1,400 calories is 1,400 calories no matter how you slice the cheesecake, experts say certain foods have a greater ability to fill you up before they fill you out. These tend to be fiber-rich, water-rich foods, like fruits, vegetables, and whole grains.
Further, Heller says, you'll get more nutrients from, say, a 100-calorie apple than from a 100-calorie portion of white bread.
"All calories are equal if all you're doing is counting calories to lose weight," Heller says. "But if you care about how you are losing weight, or controlling your hunger, or the health of your body, then no, all calories are not of equal value."
10. If you don't clean your plate, you're wasting food (don't forget those starving children Mom told you about).
Tying emotions to eating (like when you feel guilty about leaving food on your plate) sets the stage for emotional overeating, Aronowitz says. If you've been taught that cleaning your plate is the best way to show appreciation for a meal, she says, instead show your gratitude with verbal praise, by asking for the recipe, or by sending a thank-you gift or note the next day.
"Food is simply a source of fuel for the body -- not an emotional payoff or payment," says Aronowitz. If you just don't feel right leaving the table until you've cleaned your plate, she says, underestimate your hunger and put less food on your plate to begin with.