Feeling tired or lacking energy can be perfectly normal—for short periods. But if it's severe or longstanding, it can be a sign of a serious problem such as biological depression, or stress co-opting the biochemical routes used by your immune system. Complicating the problem, sluggishness can be either mental or physical. Chronic fatigue, combined with muscle weakness, can be a symptom of several developing disorders, including arthritis.

How serious is your fatigue? The following test is designed to help you pinpoint both the type and severity of your tiredness. But be warned: no simple test is conclusive. So if you are in any doubt, please consult a physician right away.

Enter a score after each question according to the following scale:

0-I seldom feel this way.

1-I sometimes (once every month or so) feel this way.

2-I often (more than once a month) feel this way.

3-I almost always feel this way.

Add up your total score and use the guidelines at the end to interpret the results.