Light at night can make you fat- and diabetic

Nobody expected this discovery by Ohio State University. Light at night apparently upsets the metabolism. Experiments with mice have shown a 50 per cent mass gain in environments exposed to even mild night light sources.

There's a reason for this apparently unkind trick of the light. Normal metabolism requires sleep, and light disturbs sleep. Eating at times when they'd normally be sleeping was one of the problems for the obese mice.

The standard light and dark cycle of 16 hours light and 8 dark is the normal diurnal rhythm. Anyone who's ever had disturbed sleep will remember vividly that feeling of disorientation afterwards.

Arguably the most disturbing thing about the study was that the mice exposed to light at night also showed level of glucose intolerance- the precursor of diabetes. This was despite the fact that these mice were otherwise the same as the controls, and equally active.