changing one's behaviors. Experts say that the most successful weight－loss plans include a well－balanced diet and exercise. People who want to avoid weight gain have to balance the number of calories they eat with the number of calories they use. To lose weight，you can reduce the number of calories you take in，increase the number you use, or both.

　　A recent study looked at four of the most popular dieting plans in the US. Researchers at Stanford University in California studied over 300 overweight women，mostly in their thirties and forties. Each woman went on one of the four plans：Atkins，The Zone, Ornish or LEARN. The women attended diet classes and received written information about the food plans.

　　At the end of the year，the women on the Atkins diet had lost the most，more than four and one－half kilograms on average. They also did better on tests for cholesterol（胆固醇）levels and blood pressure.

　　Christopher Gardner，who led the study，says the Atkins diet may be more successful because of its simple message to eat less sugar. He says that there was not enough money to study men，but that men would probably have similar results.

　　Last week，another report based on thirty－one studies suggested that only a few people have long－term success with dieting. It says those who kept the weight off generally were the ones who exercised.

24. Which is a doctor's advice for weight loss?

A. Taking medicine. B. A well-balanced diet.

C. Exercise. D. Balancing the number of calories.

25. Which diet plan is most helpful according to the study?

A. Atkins. B. The Zone.

C. Ornish. D. LEARN.

26. What is the best way to lose weight from the last paragraph?

A. To eat less. B. To eat healthy food.

C. To exercise. D. To be on diet.

27. What can we infer from the passage?

A. Men will become overweight in their thirties and forties.

B. Women gain less weight than men.