A study conducted on more than 68,000 mid-die-aged US women suggests that females whodon't get enough sleep may end up adding someextra pounds over years.
　　Researchers followed 68,183 middle-aged women for 16years and found that those who slept 5 hours or less per nightwere one third more likely to gain weight than those who sleptfor 7 hours.
　　Moreover, researchers found that the weight gain was sub-stantial with some women even gaining 33 pounds or more.