Summary: "Sleeping for under seven hours a night greatly raises the risk of catching a cold" Considering the very high degree of genetic variability in humans

Summary: "Sleeping for under seven hours a night greatly raises the risk of catching a cold" Considering the very high degree of genetic variability in humans, and the effects of food, sunlight, sport and in general life style, I suspect a much larger study would reveal a very large standard deviation around the claimed 7 hours.