Slim Down Quick

If only losing weight were like losing your car keys: frequent, effortless, and guaranteed to happen just when you have someplace important to be. Instead, excess pounds have a way of spontaneously combusting when dieting is the furthest thing from your mind--when you're in a new relationship, knocked flat by the flu, swamped at work. "Although muscle is usually the first to go in those cases, an unexpected loss of five to 10 pounds can be a good starting point for a weight loss success story," says Tara Gidus, R.D., a nutrition coach at the Human Performance Institute in Orlando, Florida. Of course, if the cause of the drop was unhealthy or impossible to maintain, it's going to take more than wishful thinking to keep the weight off. Give these expert-approved strategies a try:

New Love 

A big dinner doesn't seem so appealing when you have butterflies in your stomach. "When you're nervous or excited--as you are at the beginning of a relationship--the brain releases certain hormones, including adrenaline, that can suppress appetite," Gidus says. That's terrific--until a few months later, when your nerves calm down and your appetite ramps up. And the more time you spend with your honey, the more likely you are to pig out: According to a study presented at the 2007 annual meeting of the Obesity Society, women in cohabitating couples have higher obesity rates than singles, and newly married women gain an average of 24 pounds over five years (the average weight gain for single women is 15 pounds).

Keep it off. Your beau might be able to inhale hoagies and still bounce a dime off his abs, but don't assume you can--a guy burns about 600 more calories per day than his better half. Consider his stash of junk food officially off-limits and find guilt-free snacks: Skinny Cow ice cream bars, sugar-free Jell-O rice pudding, low-fat mozzarella sticks. Also, fill your fridge and cabinets with these foods that burn fat. If dates typically involve a knife and fork, plan them around physical activities instead --swimming, hiking, biking, or hitting the gym. Having a workout buddy boosts your chances of dropping a size or two.

The Flu

After you've been sick as a dog for a week or more, coworkers' comments about your sudden slim-down can leave you lovin' your new bod. But don't buy a new wardrobe just yet: "It's unrealistic to expect to maintain 100 percent of illness-related weight loss, because not eating is not an option," Gidus says. Chances are, the only exercise you did while you were sick was crawling back and forth between the bathroom and bed, so your muscles have begun to shrink. A study in the Journal of the American Medical Association found that just two weeks of decreased activity can lead to more belly fat and less muscle.

Keep it off. Get thee to a gym. For every pound of muscle you pack, your body burns more calories daily--and that's even when you're not exercising. And remember this: One pound of muscle takes up a lot less space than one pound of fat. So even though you might not see the difference on the scale, you will see it in the mirror. Just wait until you feel at least 80 percent healthy and have a green light from your doctor before pumping iron again, cautions Florida personal trainer Maren Piefer. She recommends three 30-minute full-body-toning sessions a week. To build lean muscle and tone without adding bulk, do lots of reps (three sets of 12 to 15 per exercise) with the heaviest weights you can lift while still maintaining proper form. Try doing two moves for each major muscle group (for example, leg curls and dead lifts for your hamstrings, pushups and flies for your chest). While you're at it, don't stop eating that chicken soup: Research from Pennsylvania State University found that eating soup before a meal reduces the amount you eat overall by 20 percent. Stick to soups that have 100 to 150 calories per serving, such as Campbell's Chunky Healthy Request Old Fashioned Vegetable Beef Soup or Progresso Roasted Chicken Rotini. Want more nosh options? Breeze throught the grocery store aisles with WH's 125 Best Packaged Foods.  

Stress

When your calendar is at maximum capacity, you can be too distracted to eat, says Suzanne Farrell, R.D., a private-practice dietitian in Denver. But when time, yoga, or your massage therapist finally kicks stress to the curb, your appetite will probably return with a vengeance. When it does, it'll be tough to keep the pre-burnout pounds from piling back on because you've picked up eating habits like skipping meals and replacing your lunch with a candy bar and more coffee.

Keep it off. Since you've been too busy to shop, your cupboards are probably bare by now. Use this opportunity to rebuild your diet from scratch, Farrell says. Pack your kitchen with the nutrient-dense foods your body needs--whole grains, fruits and veggies, low-fat dairy, lean meats, and beans--and leave out everything it doesn't. "Fill your stomach with good-for-you food and you'll be less likely to dive into the Lay's--especially if you have to go to the store to get them," Farrell says. To stay on track, try this twist on a food diary: Create separate columns for fruits, veggies, whole grains, dairy, and lean protein. Each day, when you eat a serving of one, put a mark in the appropriate column. Then tally them up: A moderately active woman who gets 30 to 60 minutes of exercise per day should have about two cups of fruit, three cups of veggies, seven ounces of whole grains, three servings of dairy, and six ounces of lean protein daily. The closer you get to these levels, the healthier (and slimmer) you'll be.

A Change of Scenery

"Skipping the country could be one of the greatest things you can do for your waistline. According to the Journal of Economic Perspectives, 25 to 30 percent of the U.S. population is obese; we out-chub United Kingdom, Canada, Spain, Italy, France, and Japan. Traveling abroad gives you a chance to take a vacation from bad diet habits, especially those triggered by your environment—like those three Krispy Kremes you pass on the way to work every day.

Keep it off. You don’t have to be in Rome to eat as the Romans do. When play time is over, ID the healthy vacation habits you want to import into your real life, Gidus says. For example, sometimes there’s not enough time or it’s too expensive to eat big meals abroad, so you graze from morning till night. "Continue eating mini-meals and snacks (300 to 400 calories apiece) every three to four hours to keep your metabolism high," she says. If you liked drinking espresso straight in Italy, start ordering a single shot at Starbucks instead of your usual 360-calorie vanilla latte. Stocking up on cookbooks from countries that eat naturally low-fat diets can also help keep the pounds at bay, Farrell says. Shop the supermarket’s international aisles for the healthy foods you ate on foreign soil, and you’ll have an easier time holding onto that vacation body all year long. Check out WH's new Ultimate Meal Plan for daily dieting tips for all-day energy and weight loss.