Already dim light is able to activate cancer-cells
A scientific study once more proved that sleep is the most important factor when it comes to prevention of diseases. But sleep is also playing an important role in healing. Here, light is one of the most important key- and control-factors. More than 25 years ago, I have developed the 10 MUST-criteria for healthy sleep in co-operation with experts. Especially for people who already suffer under a diseases – and here especially cancer – absolute darkness during sleep is important.
Cancer cells dislike darkness
When it comes to prevention and healing the circadian rhythm of a human being, meaning the rhythm of day and night, is more important than science so long assumed. Because, the one who ignores this rhythm and who likes to turn the night into the day increases the risk of activating existing cancerous cells. Scientists lately discovered that cancerous cells apparently grow especially fast when people concerned don’t sleep in total darkness. And the results of the study revealed previously unexpected things: even the success of a drug therapy of breast cancer can depend on light conditions in the night.
The US cancer scientists Steven Hill and David Blask of Tulane University, New Orleans, examined the effects of light resp. darkness on the activity of cancerous cells and the effectiveness of medications. Here, it became clear that cancer cells grow faster the brighter a person concerned sleeps. Years ago, Israeli scientists, too, pointed out this fact. The study results lead to the conclusion that only small amounts of light are enough to do so – and it doesn’t matter whether they are in the bedroom itself or penetrate from the outside from street lamps or an illuminated advertising, for example. Only this lets cancer cells divide faster than total darkness.
Melatonin lets sleep cancer cells, too
Scientist David Blask explained on July 25th 2014 in the study published in the journal “Cancer Research”: “A high level of melatonin lets breast cancer cells sleep by turning off growth mechanisms.” By the way: sleeping cancer cells are easier to fight with anti-cancer drugs like tamoxifen, for example. The fact, that light is able to suppress or delay melatonin production is known since more than two decades. Especially light with a high share of blue-light (energy-saving-lamp, PC, for example) do so in a very short time. Out of this reason a special night lighting is important. These should be a dampening light in the range of 490-650 nanometres. “But, when the light is on in the night the natural production of melatonin is inhibited. One can say, that the breast cancer cells wake up and tamixofen becomes ineffective”, so Blask.
Melatonin is a hormone that is produced in the pineal gland out of serotonin (happy hormone). Melatonin makes us tired and slows down metabolic processes. In the night it lets the body come to rest. The closer morning comes the lower the level of melatonin gets and the decelerating effect of melatonin decreases. At about 03.00 a.m. the time of the stress hormone cortisol begins. It stimulates the metabolism and prepares the body for the challenges of the following day. Hopefully, the level of the stress hormone cortisol decreases in the afternoon again and makes way for the building of melatonin in the evening.
But, the composition and decomposition of the hormones in the course of a day only run smoothly when they are supported by outer stimulants. And this is exactly where the biologic effect of light begins. In this connection it is important to mention that our inner clock is so receptive for light because of the hormone melatonin. The “blue daylight” or also artificial light (420-490 nanometres) inhibits melatonin production. In the morning, this process really awakens us and cortisol becomes fully effective.
In the evening the natural light becomes weaker and yellowish. Now, bright, artificial light with high share of blue light retards production of melatonin. The consequence: at first, we remain fit and concentrated. But, at the same time our inner clock becomes unbalanced. We are not able to fall asleep, have a lighter sleep and are unrested and not recovered. Out of this reason, a lack of melatonin is connected with sleep disturbances and low immunity. Many studies indicate that a high melatonin level in the night has a cancer-inhibiting effect.
How did the scientists find out about the effect of melatonin? You will read that in the next article.
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