People who want to lose weight and people who want to maintain their weight loss often assume the same strategies. Eat less and exercise, right? Well, yes, to a point. While watching your portions and working up a sweat are always good beauty and health plans (regardless of if you want to drop pounds or not), turns out that the way you lose weight versus the way you keep that weight off are different.If your goal is: Losing weightBe a master plannerMost of us have our schedules planned down to the last minute–from early a.m. meetings to conference calls to that dentist appointment you’re (finally!) getting around to–but rarely do we give that much thought to planning our meals.Turns out it’s in your best interest. A study from Penn State found that subjects who planned what they ate ahead of time were almost twice as likely to report successful weight loss than those who didn’t.“Aim for five small meals a day, and plan everything in advance,” says Kristin Kirkpatrick, R.D., YouBeauty Nutrition Advisor and wellness manager at the Cleveland Clinic. “Prepare your meals on the weekends when you have time, and never go more than 3 ½ hours without putting something in your mouth. Carry a low-sugar energy bar, trail mix or an apple so you’re not tempted to buy a snack from the office vending machine.”MORE: Less Sugar Diet for the Day, from Kristin Kirkpatrick, R.D.The other key to successful meal planning? Portion control. “People don’t have a running meter on their mouth that says ‘I hit 500 calories, I’m done.’ You have to control your portion sizes,” says Christopher Sciamanna, M.D., professor of medicine and public health sciences at Penn State College of Medicine.For those just starting their quest to lose weight, Dr. Sciamanna recommends pre-packaged meals. “They’re inexpensive, and they’re brainless,” he says. Caveat: Skip frozen “diet” dinners. “They tend to be low in quality nutrients and fiber,” says Kirkpatrick. Instead, choose pre-packaged meals rich in vegetables, whole grains and lean protein. Dr. Sciamanna’s pick: Kashi.Once you’ve gotten an idea of what a proper portion size looks like, you can graduate to D.I.Y. pre-packaging: Portion out your meal, then put away the serving bowl. “Don’t leave it sitting out on the table, waiting for you to refill your plate,” says Dr. Sciammana.When it comes to working out, play the fieldConventional wisdom says if you want to lose weight, you have to pick an exercise program and stick with it—but experts say that’s actually not the case.“You don’t have to exercise to lose weight. I tell my patients that every day,” says Dr. Sciamanna.Um…WHAT?“Exercise helps augment weight loss, but it actually doesn’t burn that many calories,” explains Anne McTiernan, M.D., director of the Prevention Center at the Fred Hutchinson Cancer Research Center in Seattle, WA. “If you walk on the treadmill for half an hour, then eat a 200-calorie granola bar, you’ll have undone the calorie burn you got from the treadmill.”However, before you gleefully toss your gym shoes in the trash, know that exercise does play an important role in maintaining weight loss. The smartest workout strategy: If you’re just starting out, don’t force yourself into an impossible-to-achieve workout regimen, then feel guilty because you didn’t stick with it. Instead, try out different kinds of exercise until you hit on something you enjoy. Science supports you: Researchers at Penn State found that subjects who tried out different forms of exercise were more likely to lose weight than those who attempted to adhere to a consistent routine.MORE: Fitness Expert Tracy Hafen Helps You Get Started“You have to try out different things,” says Dr. Sciamanna. “If you don’t find something that you like, you’re just not going to stick with it long-term.”Get a little help from your friendsSubjects who participated in a weight-loss program were more successful at dropping pounds than those who didn’t, according to the Penn State study. “If you go to a group-based program every week or every other week, you’ll lose weight,” says Dr. Sciamanna. “But the key is to keep going. Studies show that most people drop out within a month.”So why exactly do weight-loss programs help you shed pounds? “Many people find that programs provide social support, and help them feel accountable,” says Dr. McTiernan. Essentially, accountability means you’re reporting to someone who’s helping to track your progress: pounds lost, time spent exercising, etc. Think of it as a cross between your boss and your own personal weight-loss cheerleader. “You could also do the accountability part with your doctor or other health care provider, or a family member or friend,” adds Dr. McTiernan.And as with everything else these days, you can also go the digital route. “Some people do better with an online program they can log-in to anytime they want. It all depends on the individual,” says Kirkpatrick. “Just make sure to contact the program first, and ask for referrals and outcomes.”De-sugar your dietFrom juice to soda to pasta sauce, sugar sneaks into our diets in so many ways. “In addition to being high in calories, sugary foods tend to be very low in overall nutrition. And the more sugar you feed your taste buds, the more sugar they want,” says Kirkpatrick.COLUMN: Sneaky Sources of SugarLosing weight successfully means weaning yourself off the white stuff as much as possible. “When you’re shopping for food, avoid any products that have sugars or syrups in the first five ingredients,” says Kirkpatrick. She recommends using fresh berries in your yogurt or cereal in the morning, and sprucing up your water with fresh mint, strawberries or cucumber.One more thing: Don’t think that simply switching to artificially sweetened snacks or diet soda will be a quick fix. “Diet colas don’t take away your need and desire for sweets, and they may actually hinder your weight loss efforts,” says Kirkpatrick.If your goal is: Keeping weight offMake exercise part of your lifeIn the Penn State study, subjects who reported following a consistent workout routine were almost twice as likely to maintain their weight loss than those who didn’t. “We found that earlier in the process, people who experimented with different forms of exercise were more successful. But over time, it becomes about a routine,” explains Dr. Sciamanna. “It has to be something you don’t need to think about, and that fits into your life easily.”For the best results, Dr. McTiernan recommends at least 30 minutes of exercise per day. “Schedule it into your day like you do other appointments,” she suggests. And keep in mind that you don’t have to change into your Lululemon gear and hit the gym to reap the benefits of working out. “Take walk breaks instead of coffee breaks at work, and stand up often if you have a sedentary job,” she says.MORE: Sneak in Exercise All Day LongChoose low-fat, high-quality protein sources“We live in a carb-laden world,” says Dr. Sciamanna. And unfortunately, most of the carbs within easy reach aren’t of the high-fiber, whole-grain variety. Take a peek at your office vending machine and what do you see? Pretzels, chips, cookies and candy bars, most likely. “These snacks will only fill you up for a short period of time,” says Kirkpatrick. “You’ll be looking for something else to eat shortly after.”MORE: Your Complete Guide to SweetenersThe solution? Low-fat, high-quality protein. “Protein promotes satiety—it helps you feel full,” explains Dr. Sciamanna. Lean meats such as chicken and turkey, fish, beans, yogurt and nuts are all excellent sources of low-fat and/or high-quality protein. In fact, when researchers at Harvard University analyzed more than 20 years worth of nutritional studies, they found that yogurt and nuts were the two foods most closely tied to weight loss. Just make sure to choose yogurt without added sugar or artificial sweeteners, and if you decide to snack on nuts, portion them out beforehand so you don’t overdo it, since nuts are higher in fat content.(P.S. The Harvard study found that some of the worst offenders for weight gain included potato chips, sugar-sweetened drinks, red meat and processed meats. Surprised? Neither were we.)Remind yourself why you want to maintain your weight loss“In our research, we found that a few cognitive practices were particularly useful for weight loss maintenance,” says Dr. Sciamanna. So what exactly is a cognitive practice? Nothing more than a thought or mantra that you try to think of often.MORE: All Calories Aren’t Created Equal by Dr. Oz & Dr. RoizenIt doesn’t have to be anything complicated, and we’re not here to judge. “I want to be a fit, healthy role model for my daughter” and “I want to fit into my favorite J Brands” work equally well in our book. In this case, it’s the thought that counts!