Poor sleep can age elderly people by as much as five years

A study by Dr. Terri Blackwell of the California Pacific Medical Centre Research Institute found that quality of sleep predicted future cognitive decline. Fragmented sleep and lower sleep efficiency were associated with a 40 to 50 per cent rise in the odds of a drop in mental faculties, equivalent to a five-year increase in age. The study tested functions such as planning, decision making, error correction, trouble shooting and abstract thinking.

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