Will a glass of milk cure your insomnia?

Drinking a glass of warm milk at bedtime sometimes acts as a sleep aid, thanks in part to the sleep-inducing protein known as tryptophan.

Recent research has also found that cow’s milk, especially when harvested at night (night milk), had naturally higher levels of tryptophan. The night milk was composed of 24 percent more tryptophan and had about 10 times more melatonin, the hormone that regulates the sleep-wake cycle, than day milk.

The sedative-like effects of night milk helped reduce physical activity and increase sleep duration in mice, suggesting it may also help treat anxiety, according to the study published in  Journal of Medicinal Food.

Tryptophan is an amino acid known to promote sleep and is found in small amounts in protein foods. Normally, to produce an effect, the amino acid must cross into the brain and cause sleep and relaxation.

Researchers put the rodents to a series of tests by administering powdered milk mixed with water. The milk was collected during the day and at night. Two groups of mice were given injections of diazepam (a drug used to treat anxiety disorders) or plain drinking water, according to the study. After an hour, mice that were injected with night milk turned significantly less lively than the mice fed with day milk or water. Mice with diazepam were the least active.

Analysts also measured the groups’ balance and coordination by placing them on a rotating bar and counting the number of falls they took during a 20-minute lapse. On average, mice that drank night milk fell about four or five times, twice as much as the mice who drank day milk. Those with diazepam in their system fell as much as nine times. In comparison, mice fed with water maintained good balance and coordination by falling only twice.

“Since night milk was just administered to lab mice more research is needed before we can consider it a sleep remedy,” says Dr. Yelena Tumashova, sleep medicine specialist at Advocate Lutheran General Hospital in Park Ridge, Ill.

Dr. Tumashova offers these recommendations for improving sleep:

• Try to relax and minimize stress by reading a book or listening to music before bed
• Don’t take your cell phone or tablet with you to bed
• Exercise in the earlier part of the day