Chances are you've tried at least once to eat healthier. And, unless you are super strong-willed, chances are you didn't stay on track. Don't feel bad about it-you certainly aren't alone!

A new survey finds that nearly one in three young people embark on a new diet each month, but 45 percent give up after a week and about half abandon their goals within a month. Studies also show that rather than choosing a plan and committing to it long-term, 48 percent of dieters switch plans every six months.

In my private practice I've seen countless clients over the years struggle with stick-with-it-ness for numerous reasons. Here are the three big obstacles I see and how to overcome them so you can jump of the diet rollercoaster, stay the course, and achieve sustainable weight loss that doesn't feel like a daily struggle.

1. Choosing the Wrong Approach

Even if a weight-loss strategy works, I can guarantee that you will give up and gain all the weight back (or more) if you can't realistically see yourself eating that way every day for the rest of your life.

Nearly every client I counsel has done something drastic to shed pounds (sometimes a lot of pounds) but wound up right back where they started. And because they achieved results, many are tempted to try drastic approaches again, from fasts, detoxes, and cleanses to pre-packaged meals or ultra-strict plans that eliminate a laundry list of foods. It's not that these approaches don't cause the number on the scale to go down-it's that they aren't sustainable, and as tough as it is to accept, losing weight and keeping it off requires being in it for the long haul.

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An analogy I like to use for maintainable weight loss is getting out of debt. If your credit cards are maxed out and you're in serious financial trouble, you might be inclined to create a super-strict budget that prohibits spending any money on clothes, entertainment-everything but the bare essentials. While that may help shrink the debt quicker, before long those feelings of deprivation, boredom, and resentment kick in, and you say, "screw it" and charge dinner, a movie, and maybe a new sweater to the credit card, wiping out a good chunk of the balance you've paid down.

You can probably see the parallel to a too-strict diet and where I'm going with this. Bottom line: Adopting an unrealistic plan is bound to backfire. And while a more realistic approach may mean slower progress, it also slashes the risk of set backs, so instead of losing 30 pounds in a month and gaining it all back, you may lose five to eight pounds each month and be over 50 pounds slimmer a year from now.

2. Having an All-or-Nothing Attitude

One of the biggest barriers to success I see among my clients is the tendency to let one slip-up snowball into a major setback. You're human and perfection isn't possible, so rather than beating yourself up or saying, "I screwed up so I might as well splurge all weekend and start again on Monday," try to keep the big picture in mind.

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It's like that debt. If you went $5 over budget once, then got right back on track with your spending plan, it would derail your progress far less than if you allowed that $5 blunder turn into a $100 spending spree.

In the grand scheme of things, one "off" meal isn't that big of a deal. The best thing you can do is try to figure out what triggered you (stress, not planning ahead, letting yourself get too hungry…) so you can prevent it from happening again. Stumbling sometimes is good because it's an opportunity to learn how to better set yourself up for success.

3. Lack of Support

My husband is awesome. He's super supportive in numerous ways-but he can be a food pusher. Just last night he tried to get me to split an order of Five Guys fries with him while we were running errands, and when I said I really didn't want to, his puppy-dog eyes almost caused me to cave.

I hear stories like this from a lot of my clients. Whether it's a family member, friend, co-worker, or a social situation that revolves around food, eating healthfully can sometimes (okay, often) feel like you're swimming upstream.

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In my experience one of the most important keys to not giving up is having support. Some of my clients text me during difficult moments, but I also encourage them to find other people to reach out. Just knowing that you have even one person in your corner who really gets what you're doing and why and will be proud that you got through a tempting situation is invaluable. Even if it's a Facebook buddy you've never met in person, find someone who will make you feel like you're not in it alone. If you do, you'll be much more likely to be among the 50 percent who don't throw in the towel when things get tough.

What's your take on this topic? Please share your thought via Twitter @cynthiasass and @Shape_Magazine.


Cynthia Sass is a registered dietitian with master's degrees in both nutrition science and public health. Frequently seen on national TV, she's a SHAPE contributing editor and nutrition consultant to the New York Rangers and Tampa Bay Rays. Her latest New York Times best seller is S.A.S.S! Yourself Slim: Conquer Cravings, Drop Pounds and Lose Inches.