Work can be grueling, especially if you're a business leader. And you're not alone if you accept that a little fatigue and less sleep are necessary for success. But if you expect to stay sharp and keep on innovating in your golden years, science officially has given you one more reason to get more shuteye. Researchers now increasingly believe that a lack of sufficient sleep may contribute to the development of Alzheimer's disease.

The sleep and Alzheimer's connection

Many of the functions of sleep still remain unknown. But research led by Dr. Maiken Nedergaard showed that people have what's known as the glymphatic system. This system, which is 10 times more active when you're snoozing than when you're awake, allows cerebrospinal fluid to flow through the spaces between neurons. This process flushes proteins and other waste into the circulatory system and, eventually, out of the body. Some of the proteins normally removed are amyloid-beta proteins, the same substances that collect together to form Alzheimer's plaques, so if you cut back on your sleep and reduce the system's function, you might raise your Alzheimer's risk. Because initial work on the glymphatic system involved mice, more research is being done on the cleaning process to confirm that the process works similarly in people and to identify just how big the Alzheimer's risk might be.

Other studies support the idea that Alzheimer's and insufficient sleep are closely linked. A study of over 700 people, for example, found that people who get less than 6 hours of sleep every night have an increased risk of dementia. That same research, as well as other studies, suggest a U-shaped curve to dementia development, with too much sleep also connecting to dementia risk. Researchers suspect, however, that too much sleep is a symptom of dementia rather than a cause.

Keeping perspective

Importantly, as stresses, the notion of needing 8 uninterrupted hours of sleep is a fairly modern convention. Research actually indicates that people are designed to sleep in shorter chunks. It's actually normal, based on biology, if you wake up in the middle of the night and are awake for a while. But many people don't accept this pattern. They try to sleep more continuously because their schedules don't allow them to go back to sleep for another big chunk of time after a period of nighttime wakefulness. The body also naturally slows and asks for sleep in the afternoon due to daily circadian rhythms and the production of melatonin. Biological differences also mean that it's OK to need slightly more or less sleep than someone else. With these facts in mind, as you think about how much sleep you're getting, don't be concerned if you're not getting the recommended 6 to 8 hours all at once, be open to the idea of an afternoon nap and don't compare yourself to others.

Make no mistake--coming out on top means a lot of hard work, and the dizzying speed of development can make you feel like you'll be left in the dust if you rest. But Alzheimer's researchers are proving that sleep isn't something you can sacrifice as you compete. If you want to win, you have to stop, respect your body and give your brain a chance to downshift. Innovation--and your sanity--demand it.