Overweight has become a problem people all around the world face, and it does not look lik

e it will be solved in the near future regardless of the various efforts from all walks of life. And for those who have a heavier body than they are supposed to, one advice is given repeatedly: eat less and exercise more. This has long been the suggestion for getting rid of those extra pounds. But now it seems that all the hard work may have been in vain. Scientists say there are ten other reasons why people just keep getting bigger.

Scientists claim that sleeping habits, central heating, medicines and even some pollutants can play a role in weight gain. Lack of sleep could be partly to blame. In recent years, the average night's sleep has dropped from nine hours to just seven. Sleep lack changes levels of the hormones that regulate food intake and body fat and increase hunger and appetite.

If it is too hot or too cold, we burn calories to cool down or heat up. But if the temperature is just right, the calories may be turned into body fat instead.

Those who take medicines to control their blood pressure can often put on more weight. Similarly, studies have shown that going on the Pill can add to a woman's weight. Mother Nature may also be to blame, with our body shape being partly determined by our parents. The overweight are also more likely to be associated with partners of a similar size, and their children are more likely to be overweight.

The scientists from Yale, Cornell and Johns Hopkins published their analysis of these findings last week. Their reasoning goes like this:

1. Sleep--Too little increases appetite.

2. Medicine--Many modern medicines lead to us putting on weight.

3. Mother's age--Older women are more likely to have obese children.

4. Giving up smoking--Nicotine suppresses the appetite.

5. Getting older--Weight tends to increase with age.

What does the author think of the advice "eat less and exercise more"？

A．It may not be a solution for all who face this problem since the reasons for people's getting fat varies.

B．There are various other ways to achieve the goal of weight-loss and this is not the best one.

C．Exercise is something you will never get your returns and your efforts will be in vain.

D．It has been talked about for too long a time that a newer alternative is needed.