Take a personal inventory, then start the diet

You say you're tired of dieting, you've had enough, and this is the year you're going to do it once and for all. You're finally going to lose those 30, 60 or 80 pounds for good. Nice, but what do you do, what's going to be different from what you've done in prior years? It's so simple, right? All you have to do is eat less and exercise more. Well, not exactly. Here are a few hard realities to consider before you start.

Exercise: You think you can really lose all that weight by taking the stairs rather than the elevator or escalator? Not really. Yes, you can improve your health, but if you are seriously overweight you'll need to do a lot more than simply walking up a flight of stairs to lose a significant amount of weight and be fit. However, that doesn't mean you have to go out and run for two hours each day, either.

So what should you do?

Walk — walk for at least 60 to 90 minutes per day. Are you thinking that's too much, how could you possibly fit it into your already busy life? If so, you need to understand that you don't have to do the entire 60 to 90 minutes all at once — you just need to get it in at some point during the day. Also, you can bike, use an elliptical trainer or swim instead of walking.

What about sports like basketball, tennis, etc.? Those are good, too. The only problem is that you typically don't do them daily, and you're trying to create consistent, sustainable, automatic behaviors — which means doing the same thing every day with no breaks.

Then, in addition to the walking every day, you also need to do strength training about three times per week. Most important, pick core exercises — those that focus on your abdominal and back muscles.

Find the "Why": Why in the world do you want to lose weight? You'd better have a very clear and precise reason that will stand up to your most powerful excuses. It helps to find a good reason why. Don't just say "for my health," "to look better," "to feel better." Be specific — "I would like to be around 30 years from now when my granddaughter graduates from college." Keep in mind, if you're not sure, or you treat this glibly, there's a high likelihood you will not achieve your weight-loss goal. Think you already know? Make sure. Then write it down.

Food, Activity and Emotion Guide: Research reported in the American Journal of Preventive Medicine found that weight loss is doubled by using a food diary. Get an inexpensive 2 x 3-inch pad that fits in your pocket, or use your PDA or the memo function on your phone. Write down every single food or drink you put into your mouth. Also record where you were when you ate, and your feelings before, during and after each meal. You should do this for at least four months to see your pattern of eating, drinking, activity and emotions. At the end of the evening record this information on a chart, preferably on a computer so you can store and review it.

Compliance and Consistency: It is important to be consistent in you eating and activity habits. This means that you don't take any breaks, and you record all your food and activities each and every day. You need to be compliant for about a year to make these behaviors automatic. Research has shown that you shouldn't need to take breaks from your "diet" and newfound activities. If you have to take a break, you've made too many compromises in the first place, and your new lifestyle will not last.

Eating Out: Eating out is not the best way to lose weight. Most restaurant and prepared foods are high in calories (even when you ask to have them prepared healthfully). If you do eat out, check out all menus from restaurants you frequent before you go. Most menus are available online. Come up with three or four pre-selected healthy choices. Call ahead to find out how various dishes are prepared.

Clean Out: Get rid of ALL the foods in your home that are tempting. If you live with other people, you need to get them on board from the start — and they need to be very committed to your new lifestyle. How do you really expect to lose weight if your spouse or kids are bringing home your favorite unhealthy foods? Your willpower may last a few weeks, but certainly not a lifetime.

You Must Combine: If you think you can just diet, or only exercise away the pounds, you're mistaken. You need a combination of the two. Not only that, but you need to take a good, long look at your emotions. It's the combination of all three that will get you looking and feeling your healthiest. The increased activity revs up your metabolism, dieting lowers calorie intake and changes the energy balance in your favor, and checking your emotions — looking at why you overeat and have not committed to increase activity — helps you to stay on course.

Charles Stuart Platkin is a nutrition and public health advocate, founder of DietDetective.com, and host of the new WE television series I Want To Save Your Life. Copyright 2008-2009 by Charles Stuart Platkin. All rights reserved. Sign up for the free Diet Detective newsletter and iTunes podcast at www.DietDetective.com