Download Anxiety Study Abstract

Canadian Journal of Physiology & Pharmacology
Volume 85(9), September 2007, pp928-32
Protein Source Tryptophan as an Efficacious Treatment for Social Anxiety
Disorder: A Pilot Study
Craig Hudson MD FRCP(C)1,2 Susan Hudson MSW2, Joan MacKenzie RN3
1 Whitby Mental Health Centre, 700 Gordon St., Whitby, Ontario L1N 5S9
2 Biosential Inc. 1543 Bayview Ave., Suite 346 Toronto Ontario M4G 3B5
3 Stratford General Hospital, Department of Psychiatry, 46 General Hospital Dr.,
Stratford, Ontario N5A 2Y6
Abstract
BACKGROUND: Until recently intact protein rich in tryptophan was not seen as an
alternative to pharmaceutical grade tryptophan since protein also contains large neutral
amino acids (LNAAs) that compete for transport sites across the blood-brain-barrier.
Recent evidence indicates that deoiled gourd seed (an extremely rich source of
tryptophan - 22mg tryptophan/1g protein) when combined with glucose, a carbohydrate
that reduces serum levels of competing LNAAs, has a clinical effect similar to
pharmaceutical grade tryptophan. DESIGN: Objective and subjective measures of anxiety
in those suffering from Social Phobia were employed to measure changes in anxiety in
response to a stimulus as part of a double blind placebo controlled, cross-over study with
a wash-out period of one week between study sessions. Subjects were randomly assigned
to start with either: (1) protein source tryptophan (deoiled gourd seed) in combination
with carbohydrate; or (2) carbohydrate alone. One week after the initial session subjects
returned for a follow-up session and received the opposite treatment of that received at
the first session. SUBJECTS: All 7 subjects who began the study completed the two
week protocol. RESULTS: Protein source tryptophan with carbohydrate but not
carbohydrate alone resulted in significant improvement on an objective measure of
anxiety. CONCLUSION: Protein source tryptophan combined with a high glycemic
carbohydrate is a potential anxiolytic to those suffering from Social Phobia also known as
Social Anxiety Disorder.