You're not alone. In 2000, a poll by the National Sleep Foundation (NSF) found that just over half the United States workforce reported sleepiness on the job that interferes with the amount of work they get done; at least two-thirds of adults say that sleepiness interferes with their concentration and makes handling stress on the job more difficult. More than half of adults between the ages of 18 and 29 reported waking unrefreshed, and 40 percent of younger adults said they were sleepy at work at least two days a week.
For many, this problem can be traced to inadequate sleep. That can mean poor quality of sleep, even if you get enough hours of it. An NSF poll in 2001 found that only one-third of adults in the U.S. get the recommended eight hours of sleep per night, and that another third don't even get seven hours of sleep on weeknights. Lack of sleep can explain some daytime sleepiness, but other cases can be traced to sleep disorders that impair the quality of nighttime sleep - even if you're not aware of it. For example, sleep apnea, characterized by disruptions of air flow during the night, can wake you briefly and repeatedly. (You may not even notice.) Sleep apnea affects six million Americans, including two percent of middle-aged women, and its other symptoms include early morning headaches, depression, irritability, sexual dysfunction, and difficulties with concentration and learning.
Obesity is another common cause of daytime sleepiness. In a 1998 study at Penn State's College of Medicine researchers found that obese patients were much sleepier during the day than their normal-weight counterparts, and that their nighttime sleep was frequently disturbed. Obesity is sometimes associated with sleep apnea, but researchers suggested that the daytime sleepiness they observed in this study might be related to a metabolic abnormality. Results of the study were published in the June 1998 issue of the Archives of Internal Medicine.
Surveys have also linked daytime sleepiness to feelings of anger, stress and pessimism. You might consider whether you experience the same symptoms on weekends or during vacations. Perhaps your daytime sleepiness is related to your feelings about your work - boredom, frustration or some other negative emotion. Finally, you should get your thyroid function checked, since fatigue can be a sign of hypothyroidism.
I know of no energy supplement that will provide you with fast results in terms of banishing daytime sleepiness. But you might try ginseng, which over time can give you an energy boost and help dispel fatigue. You must take ginseng for at least a month before you can expect to notice results. You might also try cordyceps and ashwagandha, both of which are prized in their respective traditions as energy enhancers. Look for standardized extracts in capsule or tablet form, and follow dosages recommended on the products.
Andrew Weil, M.D.