Eve Van Cauter, a researcher at the University of Chicago, finds that sleep loss coincides with an increase in the odds of weight gain and increased risk of Type 2 diabetes.

ScienceDaily (Apr. 21, 2009) — Laboratory and epidemiological studies continue to show that sleep curtailment and/or decreased sleep quality can disturb neuroendocrine control of appetite, leading to overeating, and can decrease insulin and/or increase insulin resistance, both steps on the road to Type 2 diabetes.

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Dr. Van Cauter describes other recently published studies from her group, one showing that only three days sleep disruption is sufficient to increase insulin resistance in humans (thus causing the body to need higher levels of insulin) and a large epidemiological study showing that short sleep over a five year period causes an increase in systolic blood pressure.

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Dr. Van Cauter says this study found that short/poor sleep was associated with obesity regardless of age.

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See also: In Today's World, the Well-Rested Lose Respect (NPR)