You've been working hard to follow a healthy, low-calorie diet and improve your exercise habits. And your rewards have been watching your weight go down and feeling better. Now, however, for no reason you can identify, the scale has stopped budging. You've hit a weight-loss plateau.

Don't get discouraged. It's typical for weight loss to slow and even stall. By understanding what causes a weight-loss plateau, you can decide how to respond and avoid backsliding on your new healthy habits.

A weight-loss plateau is when your weight stops changing. Being stuck at a weight-loss plateau eventually happens to everyone who tries to lose weight. Even so, most people are surprised when it happens to them because they're still eating carefully and exercising regularly. The frustrating reality is that even well-planned weight-loss efforts can stall.

During the first few weeks of losing weight, a rapid drop is typical. In part, this is because when you initially cut calories, the body gets needed energy by releasing its stores of glycogen. Glycogen is a type of carbohydrate found in the muscles and the liver.

Glycogen is partly made of water. So when glycogen is burned for energy, it releases water, resulting in weight loss that's mostly water. But this effect is temporary.

As you lose weight, you lose some muscle along with fat. Muscle helps keep up the rate at which you burn calories (metabolism). So as you lose weight, your metabolism declines, causing you to burn fewer calories than you did at your heavier weight.

Your slower metabolism will slow your weight loss, even if you eat the same number of calories that helped you lose weight. When the calories you burn equal the calories you eat, you reach a plateau.

To lose more weight, you need to either increase your physical activity or decrease the calories you eat. Using the same approach that worked at first may maintain your weight loss, but it won't lead to more weight loss.

When you reach a plateau, you may have lost all of the weight you will lose on your current diet and exercise plan. Ask yourself if you're satisfied with your current weight or if you want to lose more. If you want to lose more weight, you'll need to adjust your weight-loss program.

If you're committed to losing more weight, try these tips for getting past the plateau:

• Reassess your habits. Look back at your food and activity records. Make sure you haven't loosened the rules. For example, look at whether you've been having larger portions, eating more processed foods or getting less exercise. Research suggests that off-and-on loosening of rules contributes to plateaus.
• Cut more calories. Further cut your daily calories, provided this doesn't put you below 1,200 calories. Fewer than 1,200 calories a day may not be enough to keep you from constant hunger, which increases your risk of overeating.
• Rev up your workout. Get at least 150 minutes of moderate aerobic activity or 75 minutes of vigorous aerobic activity a week, or a combination of moderate and vigorous activity. Guidelines suggest that you spread out this exercise during the course of a week. For even greater health benefit and to assist with weight loss or maintaining weight loss, at least 300 minutes a week is recommended. Adding exercises such as weightlifting to increase your muscle mass will help you burn more calories.
• Pack more activity into your day. Think outside the gym. Increase your general physical activity throughout the day. For example, walk more and use your car less, do more yardwork, or do vigorous spring cleaning. Any physical activity will help you burn more calories.

If your efforts to get past a weight-loss plateau aren't working, talk with your health care provider or a registered dietitian about other tactics to try. If you can't further decrease the calories you eat or increase your physical activity, you may want to revisit your weight-loss goal. Appreciate the weight you've lost. Maybe the number you're striving for is unrealistic for you.

Because you've already improved your diet and increased your exercise, you've already improved your health. If you're overweight or obese, even modest weight loss improves chronic health conditions related to being overweight.

Whatever you do, don't give up and go back to your old eating and exercise habits. That may cause you to regain the weight you've lost. Celebrate your success and continue your efforts to maintain your weight loss.