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When you want to go to bed but sleep escapes you, a warm glass of milk has been a long-standing solution. Any milk should do the trick, but new research suggests that some cows' milk may be more effective as a sleep aid than others.
In a Korean study highlighted in the Wall Street Journal, mice were fed dry milk powder made from cows' milk collected either during the day or at night. The milk powder was mixed with distilled water. Control mice were given doses of plain drinking water or diazepam, a drug commonly used to treat anxiety in humans.
The mice underwent a series of tests an hour after treatment. The mice that received the night milk were significantly less active than the mice fed either milk collected during the daytime or water. Only the mice fed diazepam were less active.
Balance and coordination were also tested by measuring the number of times mice fell from a rotating bar during a 20-minute period. Mice fed night milk fell four to five times, about twice as often as mice receiving day milk. The water-fed mice were most alert and only fell twice, while mice that received diazepam fell about nine times.
Milk makes a great sleep aid because it contains tryptophan and melatonin. Tryptophan is a sleep-inducing compound, while melatonin is a hormone that regulates the sleep-wake cycle. In the study, milk powder from night milk contained 24 percent more tryptophan and nearly 10 times as much melatonin as milk powder from milk collected during the day.
There's no need to sneak into the barn to collect a glass of late night milk at this point, as a similar study has not been conducted on humans yet. Still, this research sheds light on potential differences between milk collected at various times of the day and may introduce some unique benefits in the future.
(c) Hoard's Dairyman Intel 2015
December 14, 2015