Pumpkin seeds relieve anxiety via tryptophan

According to the news report on TV it must first have the oil removed for better absorption in the brain. I haven't seen that mentioned in the print articles. There is a powdered pumpkin seed product in health stores, oil removed, but City TV did not say its name.


WHITBY, Ontario -- A medical director at the Whitby Mental Health Centre is carving out a name for himself with a new study linking pumpkin seeds to the effective treatment of social anxiety disorder.
"It's a new way of thinking about how we can affect brain chemistry through foods," explains Dr. Craig Hudson.

His study was released this month by the Canadian Journal of Physiology and Pharmacology and describes that gourd seeds contain the highest concentration of tryptophan, the same amino acid found in milk in turkey, but at much higher levels.

"One gram of pumpkin seeds has the same amount of tryptophan as a full glass of milk," says Dr. Hudson.

Tryptophan can have two benefits. When processed in the central nervous system under high light conditions, it is converted to serotonin, which aids in the treatment of Depression and anxiety.

In low light conditions, it is further metabolized to melatonin, which induces a natural sleep.

But in order to better absorb tryptophan from one's blood stream into the central nervous system, it must be combined with a high glycemic carbohydrate which reduces levels of neutral amino acids that normally compete with tryptophan for absorption.

"You can eat the whole turkey and it's not going to help you sleep," adds Dr. Hudson. "But eat turkey with mashed potatoes and you'll feel sleepy."

His team developed a functional food in the form of a bar, combining deoiled butternut squash seed meal, cold pressed to maximize the concentration of tryptophan, and dextrose.

Another placebo bar was created containing dried fruit and dextrose but without any source of tryptophan. Both were made at the Guelph Food Technology Centre in Guelph.

Seven people aged 18 to 65, suffering from social phobia or extreme shyness, took part in the study conducted at Stratford General Hospital.

"When they came in we told them they would be reading a one-page passage in front of a video camera that afterwards 30 people were going to review. But there was no video tape in the camera," says Dr. Hudson.

By monitoring heart rates and through observation, the study found people were much less anxious one hour after eating the functional food compared to placebo.

Dr. Hudson, who has been studying the presence of tryptophan in pumpkin seeds since 1997 for treating sleep problems, hopes food may one day become just as accepted in treating mental illness as medication.

"It's a huge shift in thinking," says Dr. Hudson, who plans to market the functional food one day.

Although the study took place in Guelph, Stratford and Boston, Whitby Mental Health Centre is placing a greater emphasis on research, says Dr. Hudson.

"I was hired to come here a year ago and a lot of that, I think, is because of my research background," he adds.

Dr. Hudson is a former chief of staff and chief of psychiatry at Stratford General Hospital and is a contributor to the Canadian Journal of Physiology and Pharmacology, Nutritional Neuroscience, British Journal of Psychiatry and American Journal of Human Genetics.