Maintaining a Healthy Weight - Part 1

OK, you’ve reached your weight loss goal. Congratulations—you’re halfway there! Now all you have to do is make sure you’re one of the 5-10% of “weight-losers” who manage to keep it off over time. So, what are you going to do now? You probably have more questions than answers. Is it OK to stop tracking calories every day? How much more can you eat? Can you cut back on exercise? How often should you weigh yourself? How do you know if you’ve really made the kind of “lifestyle change” that will make your weight loss permanent? And most importantly, what does it really take to maintain your weight loss?
Coming up with the right answers—for you—to these and related questions is not always easy. There is no one-size-fits-all approach, and what works in one set of circumstances may change as circumstances change. To give yourself the best chance of keeping the weight off for good, you’ll need to understand what can make this so hard to do. The challenges of weight management involve both biological and psychological factors. In a series of three articles, we’ll take a look at the most common and significant challenges you're likely to run into, along with some of the strategies that successful dieters (those who have maintained their weight loss over time) have used to meet them.  (This article focuses on biological challenges, while the next two will examine some of the habits of thought associated with both failure and success.)
The Set Point Problem
Some people start regaining weight simply because they start eating a little bit more and exercising a little less, often without even noticing it. But let’s assume you’ve really taken to heart the idea of a permanent lifestyle change—does this mean you can expect smooth sailing? Sadly, no. For many, the biggest and most difficult challenge of keeping the weight off may be the fact that your body thinks you have lost too much weight, and is determined to put at least some of it back on.
One of the leading theories about obesity and weight management, called the set point theory, tells us that every individual has a natural weight—i.e., a weight that your body will try to return to and maintain whenever you have lost weight. Actually, it is a bit misleading to call your set point weight a “natural” weight, since this implies that if you gain a little weight, the natural tendency would be to drop back down again to your normal weight. In fact, gaining weight—especially quite a bit of weight—appears to raise your set point substantially, while losing weight does not automatically lower it again. If you have always gained weight easily, have a history of obesity, and/or especially if you have had to struggle with weight plateaus, food cravings, and increased appetite, you should expect that keeping it off is going to require some special attention on your part.
Your body will likely try to put on some of the weight you have lost. It accomplishes this with a complex set of metabolic adjustments that will cause you to gradually gain weight even though you are maintaining what should be—on paper—a balance between calories ingested and calories expended. Hardly seems fair, right? If you were living 40,000 years ago, before agriculture, supermarkets, and fast food, you would have been one of the “lucky” ones whose genes made you a lot more likely to survive hard times. But these days…well, you get the idea.
The good news is that it is NOT impossible to maintain your weight loss, and that you do not need to become an expert in metabolic biochemistry and food analysis, or eat rabbit food for the rest of your life. However, research has identified 3 strategies for managing set point problems:
  1. Know your caloric target for weight maintenance.
The first step towards lowering your set point weight and getting your body to cooperate with weight maintenance is to calculate how many calories you can theoretically eat every day to maintain your present weight. A simple way to figure this out is to again go through the SparkPeople goal set-up process, the way you did when you first started out. Only this time, enter your current weight as both your starting weight and your goal weight, and enter your current exercise routine as the amount of exercise you will be doing. The recommended calorie intake you get is what you should need to maintain your current weight at your current activity level, assuming no set point problems.
  1. Work up (or down) to this calorie intake gradually.
Don’t just assume you can start eating at this maintenance level right away. You need to experiment a little until you figure out what your metabolism will let you get away with. The best approach is to increase your daily calorie intake by 150-200 calories (from healthy, low-fat food sources, of course) for one week, and watch the effect that has on your weight. If you continue to lose weight, or your weight holds steady, do the same thing again for another week, and continue doing this until you either reach your estimated maintenance target, or you start gaining weight. Obviously, you will want to continue (or restart) daily recording of your calories and exercise during this period to keep things accurate, and if you have stopped weighing yourself frequently, you may want to start doing that again as well.
3.       Exercise, Exercise, Exercise.
By far the most important factor in maintaining weight loss, according to the research, is a consistently high level of regular activity and exercise. Basically, you need to convince your body that storing energy as fat to protect against potential food shortages in the future is not a smart strategy because the food supply is adequate and you need that energy NOW to keep up with the physical demands of your present environment. Most likely, you will need to increase the intensity and/or duration of your exercise and other daily activity above what you did during the weight loss phase, so that your caloric expenditure stays a little higher than your maintenance level calorie intake (as determined above). 

For most people who are successful at weight maintenance, burning an additional 150-200 calories per day (in addition to your normal daily exercise expenditure) seems to do the trick, though you may need to experiment a little bit to find out what works for you. But—make sure you do NOT reduce your calorie intake below the maintenance level in order to get out of doing more exercise or to “be safe”. To lower your set point weight, you need to avoid restricting calorie intake below your maintenance level, and rely on additional exercise, if necessary, to keep your weight stable.
Other Metabolic Issues
There is some evidence (coming from research on rats) that regaining lost weight is often associated with a change in the normal ratio of fat and carbohydrates used as fuel during various states of rest and activity. Normally, fat is the predominant source of energy at rest and during very light activity, while glucose becomes predominant when intensity of activity increases to moderate and higher levels.
However, rats who are permitted to return to unrestricted eating after weight loss, and who regain weight, show a significant increase in the use of glucose in relation to fat during rest and light activity. If this transfers to human beings (pretty likely), it could mean that the tendency to regain lost weight could depend not only on how many total calories we eat, but also on what we eat and when we eat it.
If our bodies do shift into fat-preservation mode after weight loss, in order to promote weight regain, we might be able to partially counter this effect with dietary strategies. For example, one effect of being in fat-preservation mode is increased appetite, especially for foods high in carbohydrates. To some extent, at least, a diet that relies on multiple smaller meals and is relatively higher in protein may counteract this increase in appetite (protein and frequent smaller meals are both known to increase satiety), and also promote greater utilization of fat stores for energy. We’re not talking Atkins here—just a diet that involves keeping protein near the top of the recommended range (about 30% of total calories), carbs at about 50%, and fat at around 20%. In addition, a diet that emphasizes carbs and meals that are fairly low on the glycemic index, whole grains, beans, nuts, and other foods that are high in protein would help counteract these effects.
Finally, remember that everything you’ve heard about the negative effects of chronic stress, inadequate sleep, and poor nutrition on weight management will be potentially more significant during weight maintenance. So, do your homework and read up on these issues in the Resource Center, if you haven’t already.