This week on Health Watch, we’re talking about how processes in your brain can affect your body — and vice versa. There’s a hormone called orexin that plays a big role in sleep and hunger. A lack of orexin causes narcolepsy — a disorder that causes uncontrolled sleepiness. But researchers at UT Southwestern Medical Center have found that this hormone activates a gene associated with cancer, and that in healthy tissues it affects metabolism.

In tumors, the gene allows cells to stay alive by burning sugar without oxygen. But in healthy tissues, orexin triggers the gene to burn sugar with oxygen, making cells more efficient. Essentially, it sends the metabolism into overdrive, so that even if you’re hungry, you’re awake and have energy. Dr. Devanjan Sikder, the lead author of the study, says this process makes sense in evolution because it gives organisms the energy to go look for food when they’re hungry.

Visit http://www.utsouthwestern.org/sleep  to learn more about UT Southwestern’s clinical services in sleep and breathing disorders.