Friday, September 14, 2007

Weight Loss and Exercise - Facts and Myths

Ok, time for a quiz! Which of the following are true, which are false?

1: Exercise is not very helpful at all for losing weight
2: Exercise is very important for getting to and keeping the right weight
3: An hour of exercise can be wiped out with one spoonful of food
4: Some people have a harder time losing weight than others
5: You don't need to exercise to lose weight
6: You don't need to diet to lose weight
7: Carbs are bad
8: Carbs are good
9: Fat is bad
10: Fat is good
11: A calorie is a calorie, what you eat doesn't matter
12: How you get your calories is very important

Ready for the answers? For the questions above, the answers that are true are: all of the above. The answers that are false are: all of the above. Each one contains partial truth, neglects part of the story, and may often be presented as some kind of 'secret' to weight loss success. Let's take at closer look at each of these.

1, 2, 3. Exerercise is (not) helpful for weight loss. Whether it is or not depends on goals and expectations, as well as what kind of exercise you're doing. As discussed recently, walking five days a week for a half-hour - while helpful for your heart and wellness - is only going to burn about an extra 500 calories a week. That's less than one medium shake or large burger. On the other hand, playing full court basketball for several hours a week for six months or might be enough to lose 10-15 lbs. The longer your time frame, the more frequent or energetic the exercise, the more helpful exercise will be for weight loss. If you're looking to shed 20 lbs by the big dance next month, you would need to run up and down the court for four hours a day, every day. For short term weight loss, significant changes to your diet are necessary (and beware, fast off, fast back on). As for an hour of exercise being wiped out in one spoonful, it's possible. One very heaping tablespoon of peanut butter could indeed wipe out the gains of an hour of slow walking. One spoonful of low fat ice cream won't do too much damage to an hour of jogging though. (Not that peanut butter is bad, it just contains more calories and more fat than most people think.)

4. Indeed some people DO have a harder time losing weight than others. There are differences in body chemistry, hormone levels and metabolism that do make it tougher for some people to lose weight. Typically women will also have a harder time losing weight than men. The problem with this statement is that so many people use it as an excuse for not even trying. It's harder for some people to do their taxes than for other people, but if you want to live right and do well in the long run, you need to make the effort to do both.

5, 6. You can definitely lose weight by doing just one or the other. As discussed above, exercise may take longer but can be useful to lose some weight. However, if you're eating too much, or eating the wrong thing, you'll hit a plauteau with exercise - and you'll be missing out on a lot of other health benefits from eating right. Likewise, you can cut out/cut down some foods and shed a few pounds, but will be missing the significant health benefits of consistent exercise. There is also some synergy to doing both together. When you start watching what you eat and know the calories in tempting foods and the exercise required to burn off those same calories, it can be a big motivating factor to say "no." Also, using extra workouts to counteract those days where you do blow it on the diet is good for keeping you on track and avoiding demoralization.

7, 8. Carbs are absolutely essential for your body to function. Some people have success with a low-carb diet, others don't. For me it's inconceivable to envision a long-term future where I deny myself the carbs I love, so I'm not going there just for a short-term gain. For some whose main downfall is too many carbs, it might be a good way to 'kick off' a long term change in eating habits. But unless that occurs - a long-term change in eating habits, weight taken off will not stay off. One thing that should be considered though, is that frequently we eat far too many refined or over-processed carbs, and sugars, instead of the more healthy complex carbohydrates and high fiber foods. Making some simple changes such as your choice of bread and drinks, can go a long way.

9, 10. Fats are not evil, they too are absolutely essential for the body to function. The problem, especially in America, is that we eat way too much fat in our diet. Also, there are huge differences in the health risks associated with different kinds of fats (trans, saturated, unsaturated, etc.) This is an area I need to learn more about - but I'm starting by reducing trans fats and targeting no more than 30% of my daily calories to be from fat. I'm not at this point trying to eliminate fat from everything. For me that would unsustainable, and highly demotivating. But I have switched from a couple of kinds of high fat snacks to much lower fat and healthy snacks.

11, 12. For weight management, a calorie is indeed a calorie; there's no significant difference in where it comes from. 3500 fat calories or 3500 protein calories will both net you one pound. But for healthy eating and getting what you body needs, what you eat and how you get those calories matters quite a bit. For more information on that, see "A calorie is a calorie, or is it" and "Calories + Nutrients = Food"

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