Your sister fasts on grapefruit, your coworker guzzles caffeine, and your best friend eats nothing but soup for an entire week. When it comes to losing weight, silly strategies abound. And according to experts, these techniques are not only ineffective; they can be downright dangerous. The good news: Millions of people have managed to lose weight and keep it off-without resorting to harebrained schemes. How did they do it? Read on as we reveal their 17 secrets for success.

1. Start Right. As cliche as it may sound, breakfast really is the most important meal of the day—especially when you're trying to shed pounds. A study conducted at the University of Minnesota found that those who eat a healthy breakfast tend to have a lower body mass index than those who skip the first meal of the day.

2. Stick with Cereal. It's important to eat a healthy breakfast, and you may lose even more weight by choosing cereal for your morning meal. In a recent study, people who ate cereal for breakfast every day were much less likely to be obese or have diabetes than those who didn't.

3. Go Nuts. Instead of reaching for your staple snack, eat a handful of nuts. In a study conducted by the City of Hope National Medical Center, overweight adults who consumed a moderate-fat diet with almonds lost more weight than a control group who ate the same diet without the almonds.

4. Get Your Z's. According to research by France's INSERM organization, sleep loss causes a 23 to 24 percent increase in hunger, which can mean major weight gain. Not surprisingly, studies have also shown that people who get at least eight hours of sleep a night have an easier time losing weight than those who don't.

5. Eat Slowly. When it comes to weight loss, slow and steady really does win the race—because people eat less when they savor their food. Researchers at the University of Rhode Island found that women who ate their meals quickly (in nine minutes) consumed a total of 646 calories, while those ate the same meals slowly (in 29 minutes) consumed only 579 calories.

6. Be Prepared. That vending machine at your workplace doesn't offer many nutritious food choices (neither does the office candy jar or the mall food court). That's why it's important to bring a healthy lunch and energy-boosting snacks with you to work, school, shopping, or anywhere else you'll be for extended periods of time.

7. Downsize. Restaurant portions are likely to be much larger than anything you'd prepare for yourself at home. So the next time you're dining out, ask for a take-home box when your entrée is served. Scoop half of your dish into the box, refrigerate it when you get home, and eat it for lunch or dinner the following day.

8. Buddy Up. Several studies have shown that having a diet buddy can help you lose weight faster and more effectively. At the gym, a workout partner has the same effect. So find a friend, family member, coworker, or acquaintance who shares your goals, and make a pact to support and motivate each other and achieve your objectives together.

9. Indulge Yourself. According to experts, limiting yourself to a rigid diet can lead to feelings of deprivation and undermine your weight-loss efforts. For better results, allow yourself an occasional—but modest—weekly splurge, such as a piece of angel-food cake with strawberries or a few spoonfuls of ice cream.

10. Turn off the TV. A Penn State study suggests that watching television can lead to weight gain. Researchers found that children whose parents reported that their kids watched more TV than average and ate more meals in front of the TV also ate larger quantities of food than a control group in the study.

11. Mix it Up. If you spend five days a week on the treadmill, your enthusiasm is probably zapped. So spice up your fitness routine with more adventurous options like kick-boxing, rock-climbing, or rowing. The same rule applies in the kitchen: Try new recipes and ingredients to keep food fatigue at bay.

12. Enjoy the Aroma. In a study of 3,000 volunteers, Dr. Alan R. Hirsch, neurological director of Chicago's Smell & Taste Treatment and Research Foundation, found that the more frequently people sniffed certain scents, the less hungry they were and the more weight they lost. The fragrances he used were banana, apple, and peppermint.

13.  Go Blue.  Aside from blueberries and a few purplish potatoes, there are very few blue foods found in nature—or on the supermarket shelves. Likewise, very few fast-food restaurants are decorated in blue. According to experts, the color blue calms the brain's appetite center, making you feel less hungry.

14. Buy a Pedometer. It could be the best weight-loss investment you'll ever make. In a review of nine studies published in the Annals of Family Medicine, researchers found that just wearing a pedometer led people to lose a modest amount of weight—even when they weren't on a diet.

15. Write it Down. According to a Kaiser Permanente Center for Health Research study of more than 2,000 dieters, the greatest predictor of weight-loss success was whether the dieter kept a food diary. In fact, it trumped exercise, age, and even starting body mass index.

16. Weigh in. According to the National Weight Control Registry, 75 percent of successful dieters weighed themselves at least once a week. However, experts discourage weighing yourself multiple times a day. Your weight is bound to fluctuate during a 24-hour time period, so the scale may be misleading.

17. Reap the Rewards. Losing weight is a process, and results come in stages. So set goals for yourself, and treat yourself when you meet them. If you managed to stick with your diet for a month, buy yourself a new pair of sneakers or a T-shirt. When you feel good about what you've achieved, you'll be more likely to stick to your weight-loss plan.