Put - off the light when sleep

Put-off the light when we sleep in the dark, in reality can be colaborated with body. Only in the really dark state body produce Melantonin,
one of hormone in impenetrability system which can fight and prevent various desease of breast cancer and prostate cancer.

On the contrary, sleep with aflame lamp in the night as small as any light cause production of melantonin hormone is desisted.

Biolog Joan Roberts find this secret attempt having experiment at animal. When animal given nocturnal artificial light, the melantonin was down and weaken impenetrability system of its body. In the reality, lamplight like also tv cause hormone become so tired.

Therefore, besides economizing energi, by put-off the light when sleep representing the natural way to increase body health.