Body News.

Byline: Kristin Sainani

60% of women surveyed say they get enough sleep only a few nights a week at most. --National Sleep Foundation, 2007 Sleep in America poll

Willpower Gene

Overeating has been linked to a gene involved in alcoholism and drug addiction. In a study at the State University of New York at Buffalo, people who carried a certain variant of the gene and who also found food to be a strong motivator were at highest risk for overindulging in snacks, compared with subjects who had one or neither trait. People with this gene variant (30 to 40 percent of the population) may have a deficiency in reward-signaling in the brain and must engage in more of a behavior to feel as much pleasure as those with normal signaling, explains study coauthor Jennifer L. Temple. For those susceptible to overeating, she points out that exercising "releases the same reward chemicals in the brain and can act as a substitute for food."

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Help for the Sleep-Deprived

A nasal spray in development reverses the mental effects of sleep deprivation. When monkeys were kept awake for 30 to 36 hours, they did worse on a test of memory and attention than when they were well-rested, and scans ...