If you are about to make a New Year's resolution, remember this: Keeping it is your choice.We are responsible for our lives. We may not be responsible for everything that happens to us, but we are responsible for the way we respond or react to every situation that comes our way. This is where the concept of choice comes into play. We choose our responses. For instance: Find a reason WHY you want to lose weight. It helps to know why you actually want to get in shape. For health reasons? Vanity? Think you already know? Make sure. Write it down. And make sure that it's meaningful. (Read more about "Seeing the why" at www.dietdetective.com/column/seeing-the-why.aspx.)Who's influencing your food life? Keep track of your food influences for one week. See who or what is influencing you to eat the foods that you do. Is it the TV commercials you're watching? The friends you're eating with? Family, co-workers? For every meal, pick someone or something that influenced your choice. Highlighting your influences will help you see that you can take back control of your food choices.Why experts say "don't diet; make it a lifestyle." What in the world do they mean? They mean that you need to change behaviors (diet and exercise) to lose weight, but to keep the weight off for good you must choose behaviors you can live with forever. You need to consistently question and ask yourself, "Is this 'change' I just made (read: exercising at 5 a.m. every morning) something I can do forever? Can I eat celery for breakfast every day?" (That's a joke by the way, to highlight the silly things we often do to lose weight.)Be confident: Feeling confident that you can change a behavior is one of the single biggest predictors that you will be able to change. It's called "self-efficacy," the belief in your ability to organize and execute whatever behavior you would like to modify.Look back: Taking a careful look at your past can help you determine where you want to go in the future, and it helps to make sure that you realize and recognize where you did and did not take responsibility. The past may be behind you, but thinking about and analyzing what happened is the key to your dieting future. Think of the strategies that didn't work in your previous attempts to lose weight. By looking at your failures you learn what NOT to repeat.Set goals: Setting goals is critical for achievement. You might be thinking, "Well, I've achieved plenty in the past without setting goals or planning, so why do I need to do it now?" That may be true. And you still might be able to achieve without planning; however, setting goals and planning increase the odds of your success.Be prepared: It is important to recognize that preparation will help you make better choices. Weight loss and maintenance have lots of ups and downs, and plenty of curveballs. Think about the difficult choices you face most often, and make sure to figure out the best outcomes before you face them.Charles Platkin is a nutrition and public health advocate and founder of DietDetective.com.