© n/aHaving the lights on in the evening may be damaging to health
The research shows that the body produces less of the sleep hormone melatonin when exposed to light.
Sleep patterns have been linked to some types of cancer, blood pressure and diabetes.
The US researchers also found lower melatonin levels in shift workers.
Lifestyles may have moved on from a day/night rhythm, but it seems the human body has not.
The pineal gland produces melatonin through the night and starts when darkness falls.
Researchers have shown that switching on lights in the home switches off the hormone's production.
Less melatonin
In the study, 116 people spent five days in room where the amount of light and sleep was controlled. They were awake for 16 hours and asleep for eight hours each day.
Initially the patients were exposed to 16 hours of room light during their waking hours. They were then moved onto eight hours of room light in the morning and eight hours of dim light in the evening.
The researchers found that electrical light between dusk and bedtime strongly suppressed melatonin levels. With dim light, melatonin was produced for 90 minutes more a day.
Dr Joshua Gooley, lead author from Brigham and Women's Hospital and Harvard Medical School, said:
"Our study shows that this exposure to indoor light has a strong suppressive effect on the hormone melatonin."Keeping the lights on through the night also reduced the amount of melatonin produced.
"This could, in turn, have effects on sleep quality and the body's ability to regulate body temperature, blood pressure and glucose levels."
Dr Gooley said: "Given that chronic light suppression of melatonin has been hypothesized to increase relative risk for some types of cancer and that melatonin receptor genes have been linked to type 2 diabetes, our findings could have important health implications for shift workers."
Throughout personal experience in my life I have found out that there are 2 natural forms of medicine for the human body. Sleep and fresh oxygen in low temperatures. Sleep in the older days when man was still performing manual jobs , like working in the fields came naturally. A tired body shuts down the mind too, thus providing the best kind of sleep. Unfortunately we have drifted away from nature. Using our minds during most of the day isn't really all that healthy. Basically and as far as sleeping is concerned things should be as smooth as possible. Try to relax before you go to bed , sleep in warm places as body temperature goes down during sleeping time. Switch off all the lights in the house. And by God I HATE ALARM CLOCKS ! They interrupt a natural process. For 10 years I had to get up at 5:30 in the morning so I could be at work on time. I hated that. And try to get up for work in the middle of the winter at an early hour while still being tired from the work of the previous day while your body still begs for some rest. I mean it's cruel, it's a torture. Small wonder so many people keep getting sick. What comets and natural disasters , we are killing ourselves just by the lifestyles we follow.