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A Toronto psychiatrist believes he has the answer for people who can't get to sleep at night -- a naturally occurring amino acid that he has extracted from pumpkin seeds and turned into a drink mix.

Craig Hudson says the mix does not have any risk of dependency or addiction. "You can get the same results with milk and honey, you just have to drink about 20 glasses," he said jokingly.

By removing the amino acid called tryptophan, 20 milligrams per gram of protein in pumpkin seeds, squeezing out the seeds' fatty oil, and then mixing in just the right amount of dextrose (a sugar), Dr. Hudson said, he has developed the natural sleep aid that he hopes will become as common as multivitamins are today.

Tryptophan, discovered more than a century ago by Sir Frederick Hopkins, has long been known as one of the body's fundamental building blocks for stress management and a good night's sleep. The link between tryptophan and sleeping soundly is that the amino acid is only two metabolic steps away from melatonin, which our brains release to help put us to sleep. During the day, tryptophan is converted into serotonin, the chemical that is associated with an elevated sense of calm, happiness and confidence.

When a Japanese pharmaceutical company broke into the U.S. market with a synthesized version of tryptophan made from a genetically altered bacterial culture, an outbreak of a disabling and, in some cases, deadly autoimmune illness called eosinophilia-myalgia syndrome was traced back to the contaminated drug. Canada, the United States and most European countries pulled all pharmaceutical grade versions of the medication off the shelves in 1989. It has been available by prescription only sparingly since.

Dr. Hudson's variety, he says, is all natural, just as if you would get it from many foods, including turkey, milk, gourds and nuts. But most people nowadays aren't getting enough of the essential amino acid. The body doesn't produce it, so it must come from food sources.

"Because of the way people have configured their diets these days, we're not getting the right amount of tryptophan into our bodies naturally," the clinical psychiatrist said.

He contends his drink mix, named Zenbev, is the solution for the 3.3 million Canadians 15 and older who suffer from insomnia.

Zenbev is sold at health food stores in 250-gram packages, about enough for 12 nights.

However, some sleep experts are wary of Dr. Hudson's Zenbev, saying that just because it's "natural" doesn't mean it's harmless.

"It seems these days everything is natural, and that's the problem," said Eva Libman of the Institute of Community and Family Psychiatry in Montreal, explaining that even natural products can have risks of side effects.

Another expert said that while Zenbev may not be addictive, there's always a risk of dependency.

"That means that if you don't take it, you can't get to sleep because it's been helping you every other night," said Elliott Marchant, chairman of the psychology department at Malaspina University College in Nanaimo, B.C.

Prof. Marchant said there is some evidence that tryptophan can help speed up the onset of sleep, but he is concerned that Zenbev claims to help treat a bevy of sleep problems, including trouble falling asleep initially, waking up repeatedly throughout the night, awaking too early and not being able to fall back asleep. Dr. Hudson also said his product can also alleviate stress, anxiety and depression.

"This is where I start to get really dodgy. How could all of these things be treated by one medication? I'm a little wary of anything that promises all sorts of miracles," Prof. Marchant said.

Instead, he recommends people keep regular sleep schedules even on weekends.

"People have a tendency to stay up late on Friday night, to stay up late on Saturday night, and then expect to fall asleep by 10 on Sunday night. But of course their biological clocks are all screwy."


Tips for nodding off

Having trouble falling asleep? Here are some tips that sleep experts recommend:

Make your bedroom more comfortable, keep it cool and quiet.

Get up and do something else if you have trouble sleeping. Then, go back to bed.

Drink warm milk or hot water before you go to bed.

Take a warm bath, read a little or listen to some quiet music in the evening.

Get fresh air and exercise during the day, but remember: Exercise before bed can keep you awake.

Go to bed and get up at the same time every day.

Don't take naps during the day.

Avoid coffee, tea or soft drinks in the evening.

Limit your consumption of alcohol -- it can keep you awake.

Smoking cigarettes can also act as a stimulant that disturbs your sleep.

Source: Health Canada

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