Blue light suppresses production of a brain chemical called melatonin, which helps us fall sleep.

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So after Prunier I go shopping for Scotch, then I get on the plane and fall sleep.

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Tonight, somewhere in America, a young person, let's say a young man, will struggle to fall to sleep, wrestling alone with a secret he's held as long as he can remember.

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Low doses of melatonin can also help jet-lagged travellers who awaken in the middle of the night to fall back to sleep.

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Lulled by the silence of the carriage and the prospect of alpine rail travel, I fall into a deep, childlike sleep.

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Dr Paul Goldwater, from the Women and Children's Hospital in North Adelaide, said that a recent rise in cot deaths in the state of Victoria - despite the "back to sleep" advice - raised question marks over its true role in the fall in sudden infant death.

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