Weight cycling is the repeated loss and regain of body weight. When weight cycling is the result of dieting, it is often called yo-yo dieting. A weight cycle can range from small weight losses and gains (5-10 lbs. per cycle) to large changes in weight (50 lbs. or more per cycle).

Is It Harmful?
You may have heard stories in the press claiming that weight cycling may be harmful to your health. You also may have heard that staying at one weight is better for you than weight cycling, even if you are obese. However, no convincing evidence supports these claims, and most obesity researchers believe that obese individuals should continue to try to control their body weight.

Won't Losing It Again Be Even Harder?
People who repeatedly lose and regain weight should not experience more difficulty losing weight each time they diet. Most studies have shown that weight cycling does not affect one's metabolic rate. Metabolic rate is the rate at which food is burned for energy. Based on these findings, weight cycling should not affect the success of future weight loss efforts. However, everyone, whether they have dieted or not, experiences a slowing of the metabolism as they age. In addition, older people are often less physically active then when they were younger. Therefore, people often find it more difficult to lose weight as they get older.

Will Weight Cycling Leave Me With More Fat?
Weight cycling has not been proven to increase the amount of fat tissue in people who lose and regain weight. Researchers have found that after a weight cycle people have the same amount of fat and lean tissue as they did prior to weight cycling.

What About Abdominal Fat?
Some people are concerned that weight cycling can cause more fat to collect in the abdominal area. People who tend to carry their excess fat in the abdominal area (apple-shaped), instead of in the hips and buttocks (pear-shaped), are more likely to develop the health problems associated with obesity. However, studies have not found that after a weight cycle people have more abdominal fat than they did before weight cycling.

Is Weight Cycling Harmful to My Health?
A number of studies have suggested that weight cycling (and weight loss) may be associated with an increase in mortality. Unfortunately, these studies were not designed to answer the question of how intentional weight loss by an obese person affects health. Most of the studies did not distinguish between those who lost and regained weight through dieting from those whose change in weight may have been due to other reasons, such as unsuspected illness or stress. In addition, most of the people followed in these studies were not obese. In fact, some evidence shows that if weight cycling does have any negative effects on health, they are seen mostly in people of low or normal weight. Some studies have looked at the relationship between weight cycling and risk factors for illness, such as high blood pressure, high blood cholesterol, or high blood sugar. Most of these studies have not found an association between weight cycling and harmful changes in risk factors.

Is Remaining Overweight Healthier Than Weight Cycling?
At this time, no conclusive studies have shown that weight cycling is harmful to the health of an obese person. On the other hand, the health risks of obesity are well known. The costs of obesity-related illnesses are more than $39 billion each year. Obesity is linked to serious medical conditions such as: High blood pressure, Heart disease, Stroke, Diabetes, Certain types of cancer , Gout, and Gallbladder disease. Not everyone who is obese has the same risk for these conditions--a person's sex, amount of fat, location of fat, and family history of disease all play a role in determining an individual's risk of obesity-related problems. However, experts agree that even a modest weight loss can improve the health of an obese person.

Conclusions
Further research on the effects of weight cycling is needed. In the meantime, if you are obese, don't let fear of weight cycling stop you from achieving a modest weight loss. Although health problems associated with weight cycling have not been proven, the health-related problems of obesity are well known.

Preventing Weight Gain
If you are not obese and have no risk factors for obesity-related illness, focus on preventing further weight gain by increasing your exercise and eating healthy foods, rather than trying to lose weight. If you do need to lose weight, you should be ready to commit to lifelong changes in your eating behaviors, diet, and physical activity.